CCT Advice
05-08-2012, 12:57 PM
#31
Senior Member
SuperSport
Join Date: Nov 2011
Posts: 700
This is what happens when they fail
It's more than a coincidence that most people with failed ccts find their spring broken. While it may not be the main issue, its not to be over looked.
If you look at the position of the front tensioner versus the rear you will see that it would theoretically be more difficult to get oil to the front cct, thus why the front is always the one to fail.
It's more than a coincidence that most people with failed ccts find their spring broken. While it may not be the main issue, its not to be over looked.
If you look at the position of the front tensioner versus the rear you will see that it would theoretically be more difficult to get oil to the front cct, thus why the front is always the one to fail.
05-08-2012, 01:45 PM
#32
Seasoned tech
SuperSport
Join Date: Apr 2012
Location: Issaquah, WA
Posts: 576
It's not really samantics, it's a missunderstanding of general physics. The only time the chain is slowding down the cams is when the valves are closing and trying to push the lobe up and trying to rotate the cam in a forward direction. At all other times the cam chain is pulling on the cam.
If anything the time that tensioner side of the cam chain would be loosest is on a hard acceleration as the tight side is being pulled the tightest putting the most slack on the slack side and then is when the slack side (tensioner side) would be moving around.
I guess another question for either you or Hawk would be what would be worse, reving to 9800 and cutting the throttle to decel the bike, or cutting the throttle and pulling the clutch in at the same time?
Thanks for your input on the breakages. The beat up ratchet mechanisms seems to coincide with the oil starvation theory which, as pointed out, is likey due to the orientation of the front tensioner pointing up rather than down like the rear where it can catch and hold the oil. Are there any actual oil passages to the tensioner to lubricat it or is it more or less just splash fed?
If anything the time that tensioner side of the cam chain would be loosest is on a hard acceleration as the tight side is being pulled the tightest putting the most slack on the slack side and then is when the slack side (tensioner side) would be moving around.
I guess another question for either you or Hawk would be what would be worse, reving to 9800 and cutting the throttle to decel the bike, or cutting the throttle and pulling the clutch in at the same time?
Thanks for your input on the breakages. The beat up ratchet mechanisms seems to coincide with the oil starvation theory which, as pointed out, is likey due to the orientation of the front tensioner pointing up rather than down like the rear where it can catch and hold the oil. Are there any actual oil passages to the tensioner to lubricat it or is it more or less just splash fed?
05-08-2012, 02:00 PM
#33
Out of my mind, back in 5
MotoGP
Join Date: Nov 2006
Location: Skurup, Sweden
Posts: 6,109
It's not really samantics, it's a missunderstanding of general physics. The only time the chain is slowding down the cams is when the valves are closing and trying to push the lobe up and trying to rotate the cam in a forward direction. At all other times the cam chain is pulling on the cam.
If anything the time that tensioner side of the cam chain would be loosest is on a hard acceleration as the tight side is being pulled the tightest putting the most slack on the slack side and then is when the slack side (tensioner side) would be moving around.
I guess another question for either you or Hawk would be what would be worse, reving to 9800 and cutting the throttle to decel the bike, or cutting the throttle and pulling the clutch in at the same time?
Thanks for your input on the breakages. The beat up ratchet mechanisms seems to coincide with the oil starvation theory which, as pointed out, is likey due to the orientation of the front tensioner pointing up rather than down like the rear where it can catch and hold the oil. Are there any actual oil passages to the tensioner to lubricat it or is it more or less just splash fed?
If anything the time that tensioner side of the cam chain would be loosest is on a hard acceleration as the tight side is being pulled the tightest putting the most slack on the slack side and then is when the slack side (tensioner side) would be moving around.
I guess another question for either you or Hawk would be what would be worse, reving to 9800 and cutting the throttle to decel the bike, or cutting the throttle and pulling the clutch in at the same time?
Thanks for your input on the breakages. The beat up ratchet mechanisms seems to coincide with the oil starvation theory which, as pointed out, is likey due to the orientation of the front tensioner pointing up rather than down like the rear where it can catch and hold the oil. Are there any actual oil passages to the tensioner to lubricat it or is it more or less just splash fed?
Now, are we done with this fencing? If you want to keep going in this direction, I'll refer you to my sigline... Otherwise, pull your head out of your ***, and act politely, even if people happen to have a differing opinion, or I'll simply ignore you... I did NOT step into this defending Hawk, or choosing sides, you where both borderline to start with... You choose to reply to my neutral statement that I considered some of your questions "off", by telling me I don't understand basic physics... That's not neutral... That's stupid...
Now, if you had done some reading in the older posts about CCT's you would already know a lot of what you are asking... So unless you prefer spending a lot of time reading and sifting, play nice, and I'll gladly argue or discuss the topic backwards, sideways and upside down with you...
For now g'nite, I'll be sleeping the next couple of hours, so don't go burning the place down until I get back... (Different timezone)
BTW, two questions for you... If your interpretation of physics are spot on, why does 99% of the CCT failures occur under light load, and why does the people that by instinct shut the throttle off when they hear the rattle get the worst damage, and not the one's like me who knew what it was and coasted to a stop by slowly closing the throttle and not damaging anything but the CCT?
Last edited by Tweety; 05-08-2012 at 02:08 PM.
05-08-2012, 02:01 PM
#34
Banned
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Join Date: Aug 2007
Location: Lake View Terrace, CA
Posts: 5,942
Well that is what I get for believing that someone who has proved they want to argue just for argument sake really would like a honest answer....
Also sorry if I think how a cct and an overhead cam set up works is pretty basic. So I try to keep things as basic as possible in my reply and now I have someone trying to crucify me for it.
I don't say hey dumbass or anything just make a statement about lets talk some basics and I have to be attacking someone....really..... are people that thin skinned around here.
All I have tried to do is pass on knowledge gained from many years around bikes and almost 15 yrs with a SH and now all I get is someone with an agenda to prove everything I say just has to be wrong.....
Though I guess Tweety doesn't know anything either as he has basically said the same thing as I have, yes there are a few differences but like I said basiclly the same thing. I also admit my explanation might be considered boarder line but but I was trying to keep things simple as possible
Yes he has seen more broken CCTs (maybe it's because the folks around me tend to believe what I tell them and follow my advice....) but other than adding the ratchet mechanism wear has basically said much the same things I have. Also I'm just going from memory and might leave a step or fact out....so sorry as I haven't seen a failed unit in years and one fact or part slipped my mind, so sorry guess I should be shot for that.
So I guess I have learned my lesson of trying to help people out and will just keep my big mouth shut.
Carry on.
Also sorry if I think how a cct and an overhead cam set up works is pretty basic. So I try to keep things as basic as possible in my reply and now I have someone trying to crucify me for it.
I don't say hey dumbass or anything just make a statement about lets talk some basics and I have to be attacking someone....really..... are people that thin skinned around here.
All I have tried to do is pass on knowledge gained from many years around bikes and almost 15 yrs with a SH and now all I get is someone with an agenda to prove everything I say just has to be wrong.....
Though I guess Tweety doesn't know anything either as he has basically said the same thing as I have, yes there are a few differences but like I said basiclly the same thing. I also admit my explanation might be considered boarder line but but I was trying to keep things simple as possible
Yes he has seen more broken CCTs (maybe it's because the folks around me tend to believe what I tell them and follow my advice....) but other than adding the ratchet mechanism wear has basically said much the same things I have. Also I'm just going from memory and might leave a step or fact out....so sorry as I haven't seen a failed unit in years and one fact or part slipped my mind, so sorry guess I should be shot for that.
So I guess I have learned my lesson of trying to help people out and will just keep my big mouth shut.
Carry on.
Last edited by 8541Hawk; 05-08-2012 at 02:07 PM.
05-08-2012, 03:37 PM
#36
Senior Member
MotoGP
Join Date: Jul 2010
Location: Phoenix, AZ
Posts: 3,869
GTS, just FYI, every single question you have asked and theory that you have proposed so far has already been discussed somewhere in this forum. I've read the threads. I'm not at all proposing that I have more knowledge of what is going on and just that you have thought to ask them in so short of time shows that your motorcycle knowledge is beyond mine. And I'm definitely not opposed to seeing discussion again (and wouldn't expect anyone to necessarily sit and weed through all of the old threads so quickly). This bike and the people who have owned it have tried many-a-thing since it was born. It's not like this is the first year that it's released and we're trying to work out unforeseen quirks or anything. Hell, a lot of the experts have left the bike and the forum, some leaving traces of intuition in the old threads.
Please don't take this as intending to be offensive, I'm just trying to give you a feel for what this bike's been through, and why your comments generate certain responses...
Also, I may have threw in the wheelie thing because lack of oil to the front CCT has been suggested as to why it breaks more often than the rear (spring failure as one one of the ways it breaks). Extended or 12 o'clock wheelies on this motor may make it so that far less oil gets to the CCT from my understanding.
Please don't take this as intending to be offensive, I'm just trying to give you a feel for what this bike's been through, and why your comments generate certain responses...
Also, I may have threw in the wheelie thing because lack of oil to the front CCT has been suggested as to why it breaks more often than the rear (spring failure as one one of the ways it breaks). Extended or 12 o'clock wheelies on this motor may make it so that far less oil gets to the CCT from my understanding.
Last edited by 7moore7; 05-08-2012 at 03:44 PM.
05-08-2012, 03:43 PM
#37
Banned
MotoGP
Join Date: Aug 2007
Location: Lake View Terrace, CA
Posts: 5,942
Spec on them is every second valve adjustment which would be 32K miles.
No you won't find it in the manual, there was a bulletin but I haven't been able to locate it and my copy is somewhere but after 4-5 moves I haven't seen it in a while.
Also I do believe there are advantages and disadvantages to either type.
The Autos can be made to work fine but do need to be replaced but are easier to install
The manuals are tougher to install and can cause major damage if done incorrectly but once they are set your good to go and should never have to mess with them.
I have autos in mine mainly because every time I go to replace mine they have been what I could get without waiting.
I plan on putting in manuals the next time just because I have replaced mine 3 times now, but I do put a lot of miles on my bike.
So in the end it comes down to which unit you are more comfortable installing and which ones let you sleep the best at night.
Also as a P.S. of sorts I always recommend on a new to you bike, no matter what the mileage as you don't know what was done to them before you got the bike and it is cheaper to replace them and know for sure than to have the head repaired.
05-08-2012, 04:47 PM
#38
Seasoned tech
SuperSport
Join Date: Apr 2012
Location: Issaquah, WA
Posts: 576
Tweety I apologize, my comment about general physics wasn’t directed towards you, and you obviously took great offence thinking it was. When you initially said “if I wanted to argue semantics” I thought you were referring to arguing them with Hawk and that is what I was referring to. I find your explanations are actually inconsistent with what hawk had said on a couple of your points and to be accurate.
1) Probably because 95+% of the time the bikes are under light load. So it is most likely to let go when the engine is under light load.
When mine came out I was under constant throttle on the freeway. I know I didn't chop the throttle because the rattle came on slower and I recognized it as cam chain rattle which normally wouldn’t be any big deal other than the tensioner had actually fallen completely out, which I didn’t know at the time, then the knocking started and I pulled over. Then the damage was done, bent valves and broken guides.
2) Could be as simple as you got lucky. Or because you kept from any sudden rpm changes which kept more consistent tension on the pull side of the chain keeping the chain pulling in the teeth of the sprockets.
I would certainly hope the lesson that you learned is to take a few steps back, take a couple deep breaths, don’t be so thin skinned and don’t take so much offense when someone asks questions that may make you think outside your normal thought process before you go trashing that person in other threads because you never know when that person actually has a clue and it might come back to bite you in the butt.
7moore7 thanks for your comments and I don’t take what you are saying in offense in the slightest. I do get what you are saying and I understand that while I’m new to this forum the forum isn’t new and much of this has been discussed. I guess the point of my asking the questions that I’ve asked, as stated above, is so that some of the information that’s been posted that may be a bit off may get a bit more straightened out. Initially I just honestly wanted to know the theory behind what hawk was saying. It was as I expected and a bit off which is why I asked the questions rather than blasting out the answers in hopes it would stimulate more conversation than him firing back with condescending comments and jabs to which I was apparently incorrect.
I already know the answers to most of the questions I've asked. The reason I posed the questions is to make people think about what they are saying, rather than just repeat what they've heard, with real thought behind it, and in an attempt to keep the conversation from getting heated by telling someone they’re wrong.
BTW, two questions for you... If your interpretation of physics are spot on, why does 99% of the CCT failures occur under light load, and why does the people that by instinct shut the throttle off when they hear the rattle get the worst damage, and not the one's like me who knew what it was and coasted to a stop by slowly closing the throttle and not damaging anything but the CCT?
BTW, two questions for you... If your interpretation of physics are spot on, why does 99% of the CCT failures occur under light load, and why does the people that by instinct shut the throttle off when they hear the rattle get the worst damage, and not the one's like me who knew what it was and coasted to a stop by slowly closing the throttle and not damaging anything but the CCT?
1) Probably because 95+% of the time the bikes are under light load. So it is most likely to let go when the engine is under light load.
When mine came out I was under constant throttle on the freeway. I know I didn't chop the throttle because the rattle came on slower and I recognized it as cam chain rattle which normally wouldn’t be any big deal other than the tensioner had actually fallen completely out, which I didn’t know at the time, then the knocking started and I pulled over. Then the damage was done, bent valves and broken guides.
2) Could be as simple as you got lucky. Or because you kept from any sudden rpm changes which kept more consistent tension on the pull side of the chain keeping the chain pulling in the teeth of the sprockets.
You say that and yet you make condescending comments in your reply! I am in no way trying to argue for arguments sake, but rather just trying to make sure the info out there is accurate. Especially when it’s coming from a high profile member such as yourself that a lot of people look up to and take every word you say as gospel. Much like pointing out a hot wire run in a fuel line holder from someone who says they own a bike shop. ;-)
I don't say hey dumbass or anything just make a statement about lets talk some basics and I have to be attacking someone....really..... are people that thin skinned around here.
Your “basic motorcycle class time” comment was clearly a dig.
Also sorry if I think how a cct and an overhead cam set up works is pretty basic. So I try to keep things as basic as possible in my reply and now I have someone trying to crucify me for it. I’m in no way trying to crucify you. Basic is good as it makes it so everyone can understand, however it doesn’t do any good to try to make it so basic that it’s inaccurate.
All I have tried to do is pass on knowledge gained from many years around bikes and almost 15 yrs with a SH and now all I get is someone with an agenda to prove everything I say just has to be wrong....I’ve seen you post some great information on this forum and this forum is better with you being here and that information you’ve provided. It’s obvious that you’ve got a lot of great experience specifically with the SH. I don’t have an agenda to prove everything you say wrong as just as I’ve said above you’ve got some great information. However your preemptive personal attacks toward me just raised awareness to what you say and its accuracy.
Though I guess Tweety doesn't know anything either as he has basically said the same thing as I have, yes there are a few differences but like I said basiclly the same thing. I also admit my explanation might be considered boarder line but but I was trying to keep things simple as possible Actually what you and Tweety have said is basically different. You go on to describe all these great stresses on the CCT’s caused by the great amount of engine breaking on decel and he says “none of it is an unreasonable load”
So I guess I have learned my lesson of trying to help people out and will just keep my big mouth shut.
I don't say hey dumbass or anything just make a statement about lets talk some basics and I have to be attacking someone....really..... are people that thin skinned around here.
Your “basic motorcycle class time” comment was clearly a dig.
Also sorry if I think how a cct and an overhead cam set up works is pretty basic. So I try to keep things as basic as possible in my reply and now I have someone trying to crucify me for it. I’m in no way trying to crucify you. Basic is good as it makes it so everyone can understand, however it doesn’t do any good to try to make it so basic that it’s inaccurate.
All I have tried to do is pass on knowledge gained from many years around bikes and almost 15 yrs with a SH and now all I get is someone with an agenda to prove everything I say just has to be wrong....I’ve seen you post some great information on this forum and this forum is better with you being here and that information you’ve provided. It’s obvious that you’ve got a lot of great experience specifically with the SH. I don’t have an agenda to prove everything you say wrong as just as I’ve said above you’ve got some great information. However your preemptive personal attacks toward me just raised awareness to what you say and its accuracy.
Though I guess Tweety doesn't know anything either as he has basically said the same thing as I have, yes there are a few differences but like I said basiclly the same thing. I also admit my explanation might be considered boarder line but but I was trying to keep things simple as possible Actually what you and Tweety have said is basically different. You go on to describe all these great stresses on the CCT’s caused by the great amount of engine breaking on decel and he says “none of it is an unreasonable load”
So I guess I have learned my lesson of trying to help people out and will just keep my big mouth shut.
I would certainly hope the lesson that you learned is to take a few steps back, take a couple deep breaths, don’t be so thin skinned and don’t take so much offense when someone asks questions that may make you think outside your normal thought process before you go trashing that person in other threads because you never know when that person actually has a clue and it might come back to bite you in the butt.
7moore7 thanks for your comments and I don’t take what you are saying in offense in the slightest. I do get what you are saying and I understand that while I’m new to this forum the forum isn’t new and much of this has been discussed. I guess the point of my asking the questions that I’ve asked, as stated above, is so that some of the information that’s been posted that may be a bit off may get a bit more straightened out. Initially I just honestly wanted to know the theory behind what hawk was saying. It was as I expected and a bit off which is why I asked the questions rather than blasting out the answers in hopes it would stimulate more conversation than him firing back with condescending comments and jabs to which I was apparently incorrect.
05-08-2012, 05:50 PM
#39
Senior Member
MotoGP
Join Date: Jul 2010
Location: Phoenix, AZ
Posts: 3,869
Although now I'm a little lost in the discussion... from my understanding, the crank puts considerable tension on the cam sprockets during acceleration on the non CCT side via the cam chain. When decelerating, this load is transferred to the CCT side.
Wouldn't that mean that closing the throttle quickly would transfer this load quickly? Has anyone disagreed with this? So during deceleration, the CCT is taking up the slack AND the cam chain load (rather than the load being on one side and the slack on the other).
Wouldn't that mean that closing the throttle quickly would transfer this load quickly? Has anyone disagreed with this? So during deceleration, the CCT is taking up the slack AND the cam chain load (rather than the load being on one side and the slack on the other).
05-08-2012, 06:11 PM
#40
Banned
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Join Date: Aug 2007
Location: Lake View Terrace, CA
Posts: 5,942
Like I have said, you are on a mission to try and either discredit me or prove everything I say is wrong...
So as I have no grasp of what is going on and you are the expert lets take your statement of:
So you don't think the cams trying to push open the valves actually slows them down faster than the cam chain would?
So my question would be what happens if say the intake valves are in the open position when you slam the throttle shut.
If the cam chain is not controlling the speed of the cam wouldn't it speed up due to the valve springs opening and pushing the cam up?
Wouldn't the tensioner now have a load on it because the cam should accelerate in this condition and the crank is trying to decelerate?
or does the cam just go on it's merry way until it tries to open the valves again?
Plus you can tell by your answer your still upset because I questioned the fact that you list yourself as an experienced tech and have your own bike business but don't seen to be able to read a service manual and have to ask about a non existent part in the head of a SH.
And yeah it was a jab at you because of your rudeness and you comment about what I was talking about was BS in another thread....
In fact it seems you are so upset and vindictive that you have gone through everyone of my old post just trying to find anything..... Just exactly how many years ago did I ask the guy about running a hot lead in the same clamp as his fuel line.... are you really that obsessed??
So as I have no grasp of what is going on and you are the expert lets take your statement of:
So you don't think the cams trying to push open the valves actually slows them down faster than the cam chain would?
So my question would be what happens if say the intake valves are in the open position when you slam the throttle shut.
If the cam chain is not controlling the speed of the cam wouldn't it speed up due to the valve springs opening and pushing the cam up?
Wouldn't the tensioner now have a load on it because the cam should accelerate in this condition and the crank is trying to decelerate?
or does the cam just go on it's merry way until it tries to open the valves again?
Plus you can tell by your answer your still upset because I questioned the fact that you list yourself as an experienced tech and have your own bike business but don't seen to be able to read a service manual and have to ask about a non existent part in the head of a SH.
And yeah it was a jab at you because of your rudeness and you comment about what I was talking about was BS in another thread....
In fact it seems you are so upset and vindictive that you have gone through everyone of my old post just trying to find anything..... Just exactly how many years ago did I ask the guy about running a hot lead in the same clamp as his fuel line.... are you really that obsessed??
Last edited by 8541Hawk; 05-08-2012 at 09:07 PM.
05-08-2012, 08:19 PM
#41
Senior Member
Superstock
Join Date: Mar 2009
Location: south nj (philly area)
Posts: 277
If the ccts were subjected to unreasonable forces during decel they would all break... that being said the definition of unreasonable forces lies with the strength of materials used obviously the ccts can handle the stress they are placed under the question is for how long the more often you put higher stress on them the faster they will break... to say that the highest point of stress is during hard acceleration is just wrong... on most and definitely the sh the load on the cct is on decel the cam lobes place very little stress on the cam chain more stress is added by the switch from compression to power stroke at the crank shaft and to slow quickly from max power to minimum power is gonna switch the stress to the back side (tensioner) thats why the tensio.er is on that side on any engine ive ever worked on...15 years of being an auto tech ive seen alot of timing belts and chains... if you look at the rotation direction they put the tensioner on the back side where as the front side usually has a straight run from cam to crank if not its a idler in between for space and routing issues...
05-08-2012, 09:28 PM
#42
Banned
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Join Date: Aug 2007
Location: Lake View Terrace, CA
Posts: 5,942
Like I have said, it seems to me just the main issue here is someone with an ax to grind trying to discredit anything I say..... Sure I will admit I probably should have used the term "Higher than optimal load" instead of massive load but really this much crap over the semantics of a sentence.
Other than that I will stand by my post of how the valve train works and what causes CCT failure on a SH.
Also it's engine braking when you use the engine to slow down and engine breaking when you snap the throttle shut on over rev.....
Other than that I will stand by my post of how the valve train works and what causes CCT failure on a SH.
Also it's engine braking when you use the engine to slow down and engine breaking when you snap the throttle shut on over rev.....
05-08-2012, 09:50 PM
#43
Senior Member
SuperSport
Join Date: Nov 2011
Posts: 700
You guys should take the personal arguments to your pm boxes, or at least keep the arguments strictly cct related.
As far as I'm concerned, there is a chance they will fail, and that's not a chance I'm willing to take. Probably because I commute daily and can't afford to have it be down, but also because it is an easy preventative measure.
As far as I'm concerned, there is a chance they will fail, and that's not a chance I'm willing to take. Probably because I commute daily and can't afford to have it be down, but also because it is an easy preventative measure.
05-09-2012, 04:02 PM
#44
Seasoned tech
SuperSport
Join Date: Apr 2012
Location: Issaquah, WA
Posts: 576
7moore7 if the cams had enough weight that the inertia of them overcame the forces of the valve spring then yes the cam chain would need to hold them back to slow them down. However the springs are way more than enough to overcome the inertia of the cams and will slow them down much faster than the crank.
So as I have no grasp of what is going on and you are the expert lets take your statement of:
So you don't think the cams trying to push open the valves actually slows them down faster than the cam chain would?
So my question would be what happens if say the intake valves are in the open position when you slam the throttle shut.
If the cam chain is not controlling the speed of the cam wouldn't it speed up due to the valve springs opening and pushing the cam up?
Wouldn't the tensioner now have a load on it because the cam should accelerate in this condition and the crank is trying to decelerate?
or does the cam just go on it's merry way until it tries to open the valves again?I actually answered that back in post #32. This is the only time the cam chain is “holding back” the cams. However throttle position is irrelevant. The valve spring is pushing back on the cam the same amount regardless of throttle position.
Plus you can tell by your answer your still upset because I questioned the fact that you list yourself as an experienced tech and have your own bike business but don't seen to be able to read a service manual and have to ask about a non existent part in the head of a SH. Ever think that because I actually read the manual and didn’t see it in there I just wanted to check to make sure this wasn’t a part that had fallen out of the head when I wasn’t paying attention. It fit in a couple of the oil passages perfectly, and though I’ve had many heads off bikes I had never had a Superhawk head off before.
And yeah it was a jab at you because of your rudeness and you comment about what I was talking about was BS in another thread.... That is false. I never said what you were talking about was BS, especially prior to your personal attack. And I wasn’t rude other than to ask for more information because I found the topic you brought up to be interesting and I wanted to learn more about it. It wasn’t until your preemptive attack that things in that thread even went south.
In fact it seems you are so upset and vindictive that you have gone through everyone of my old post just trying to find anything..... Just exactly how many years ago did I ask the guy about running a hot lead in the same clamp as his fuel line.... are you really that obsessed??
Actually I didn’t even know you had posted in that thread until I started reading it. I was using the SEARCH for other information and that thread had come up.
Maniac2313I no one has said the most stress is put on the tensioners on acceleration. You are correct that all cam chain/belt tensioners are on the non-driven side of the chain/belt. If they weren’t the cam timing wouldn’t be accurate as every time the tensioner moved it would change timing and therefore performance. Also that side is always tight so the tensioner is simply there to take up the slack on the slack side. The cam lobes are where ALL the stress comes from on the cam and with the very little weight of the cam would stop the cams almost instantly if the cam chain broke. WAY faster than the crank and the rest of the rotating assembly would stop.
The cams, cam chain, valves, and tensioner don’t care one bit weather the engine is on a hard accel, decel, or just cruising. They are just spinning around opening and closing the valves.
You never answered my question before. Which do you think would be worse? Revving to 9800rpm and slamming the throttle shut and engine breaking, or pulling the clutch in and letting it drop to idle? And why?
So as I have no grasp of what is going on and you are the expert lets take your statement of:
So you don't think the cams trying to push open the valves actually slows them down faster than the cam chain would?
So my question would be what happens if say the intake valves are in the open position when you slam the throttle shut.
If the cam chain is not controlling the speed of the cam wouldn't it speed up due to the valve springs opening and pushing the cam up?
Wouldn't the tensioner now have a load on it because the cam should accelerate in this condition and the crank is trying to decelerate?
or does the cam just go on it's merry way until it tries to open the valves again?I actually answered that back in post #32. This is the only time the cam chain is “holding back” the cams. However throttle position is irrelevant. The valve spring is pushing back on the cam the same amount regardless of throttle position.
Plus you can tell by your answer your still upset because I questioned the fact that you list yourself as an experienced tech and have your own bike business but don't seen to be able to read a service manual and have to ask about a non existent part in the head of a SH. Ever think that because I actually read the manual and didn’t see it in there I just wanted to check to make sure this wasn’t a part that had fallen out of the head when I wasn’t paying attention. It fit in a couple of the oil passages perfectly, and though I’ve had many heads off bikes I had never had a Superhawk head off before.
And yeah it was a jab at you because of your rudeness and you comment about what I was talking about was BS in another thread.... That is false. I never said what you were talking about was BS, especially prior to your personal attack. And I wasn’t rude other than to ask for more information because I found the topic you brought up to be interesting and I wanted to learn more about it. It wasn’t until your preemptive attack that things in that thread even went south.
In fact it seems you are so upset and vindictive that you have gone through everyone of my old post just trying to find anything..... Just exactly how many years ago did I ask the guy about running a hot lead in the same clamp as his fuel line.... are you really that obsessed??
Actually I didn’t even know you had posted in that thread until I started reading it. I was using the SEARCH for other information and that thread had come up.
Maniac2313I no one has said the most stress is put on the tensioners on acceleration. You are correct that all cam chain/belt tensioners are on the non-driven side of the chain/belt. If they weren’t the cam timing wouldn’t be accurate as every time the tensioner moved it would change timing and therefore performance. Also that side is always tight so the tensioner is simply there to take up the slack on the slack side. The cam lobes are where ALL the stress comes from on the cam and with the very little weight of the cam would stop the cams almost instantly if the cam chain broke. WAY faster than the crank and the rest of the rotating assembly would stop.
The cams, cam chain, valves, and tensioner don’t care one bit weather the engine is on a hard accel, decel, or just cruising. They are just spinning around opening and closing the valves.
You never answered my question before. Which do you think would be worse? Revving to 9800rpm and slamming the throttle shut and engine breaking, or pulling the clutch in and letting it drop to idle? And why?
05-09-2012, 05:22 PM
#45
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I'm having a little hard time envisioning this. Perhaps I'm overthinking it? I even drew it out trying to make sense of everything, haha! When the motor is accelerating, there is more tension pulling on the cam sprockets from the non CCT side of the chain. I'm not so sure of this even now from your statement:
I thought the timing crank, just by turning the chain, is putting more load on one side of the chain than the other... it pulls the chain, not pushes it, right? Not that it "cares" so to speak as it is designed to do this, but the tension is there. This would also make sense to me b/c the slack is taken up on the opposite side of the CCT, meaning that there will be less pressure on the tensioner... the crank is pushing the slack into it and pulling the chain tight on the other side.
Ok, if this isn't true, then the rest of what I'm confused about is just gibberish:
Where is the force on the cam chain when you're decelerating? There's no possible way everything is just spinning in there on it's own accord at the exact speed that the bike is slowing down. So is the crank slowing the rest of the components down (this was an assumption that I made before, although now I can't figure out why I made it), or are the cam lobes/ valve spring combos slowing down faster? One of the two has to be making the initiative, because the bike slows down faster than if you were to just let it coast. Unless there is some other factor that I'm not thinking of...
Ok, if this isn't true, then the rest of what I'm confused about is just gibberish:
Where is the force on the cam chain when you're decelerating? There's no possible way everything is just spinning in there on it's own accord at the exact speed that the bike is slowing down. So is the crank slowing the rest of the components down (this was an assumption that I made before, although now I can't figure out why I made it), or are the cam lobes/ valve spring combos slowing down faster? One of the two has to be making the initiative, because the bike slows down faster than if you were to just let it coast. Unless there is some other factor that I'm not thinking of...
05-09-2012, 10:19 PM
#47
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Theoretically, and I'm a little buzzed so maybe its just alchoretically, but since all of the sprockets are spinning the same direction, wouldn't tension be equal throughout the length of the chain? No sprocket is spinning faster than the others, so each sprocket would pull and push on the chain with the same force direction and speed. With the tensioner taking up the slack, the force on the tensioner is always constantly the same, and only changes as the chain stretches.
Makes sense in my mind, but I'm no physicist.
Makes sense in my mind, but I'm no physicist.
05-10-2012, 03:55 AM
#48
Former Superchicken Owner
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Theoretically, and I'm a little buzzed so maybe its just alchoretically, but since all of the sprockets are spinning the same direction, wouldn't tension be equal throughout the length of the chain? No sprocket is spinning faster than the others, so each sprocket would pull and push on the chain with the same force direction and speed. With the tensioner taking up the slack, the force on the tensioner is always constantly the same, and only changes as the chain stretches.
Makes sense in my mind, but I'm no physicist.
Makes sense in my mind, but I'm no physicist.
05-10-2012, 05:39 AM
#49
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Theoretically, and I'm a little buzzed so maybe its just alchoretically, but since all of the sprockets are spinning the same direction, wouldn't tension be equal throughout the length of the chain? No sprocket is spinning faster than the others, so each sprocket would pull and push on the chain with the same force direction and speed. With the tensioner taking up the slack, the force on the tensioner is always constantly the same, and only changes as the chain stretches.
Makes sense in my mind, but I'm no physicist.
Makes sense in my mind, but I'm no physicist.
So, what I'm thinking is, the drive sprocket pulls on one side of the chain and pushes it through the other side, causing the chain to be "tighter" on one side as it pulls on the cam lobes under acceleration. You don't see this happen really because like Rwhisen said, all of the slack is taken up by the CCT and the parts are made of metal.
What I still don't know is which of the sprockets are slowing down faster or resisting slowing down under heavy engine braking. When I say slowing down faster, they aren't actually traveling faster b/c the cam chain keeps them traveling at the same speed, but their momentum/spring force/compression force or whatever is causing them to put tension on the chain in some direction.
05-10-2012, 09:46 AM
#50
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Well, I didn't mean that any of them are actually spinning faster (because the chain forces them to stay the same), but one of the sprockets has to be driving the others to some degree... if you took the chain off and tried to start the bike, the drive sprocket would spin and the cam sprockets would just sit there.
So, what I'm thinking is, the drive sprocket pulls on one side of the chain and pushes it through the other side, causing the chain to be "tighter" on one side as it pulls on the cam lobes under acceleration. You don't see this happen really because like Rwhisen said, all of the slack is taken up by the CCT and the parts are made of metal.
What I still don't know is which of the sprockets are slowing down faster or resisting slowing down under heavy engine braking. When I say slowing down faster, they aren't actually traveling faster b/c the cam chain keeps them traveling at the same speed, but their momentum/spring force/compression force or whatever is causing them to put tension on the chain in some direction.
So, what I'm thinking is, the drive sprocket pulls on one side of the chain and pushes it through the other side, causing the chain to be "tighter" on one side as it pulls on the cam lobes under acceleration. You don't see this happen really because like Rwhisen said, all of the slack is taken up by the CCT and the parts are made of metal.
What I still don't know is which of the sprockets are slowing down faster or resisting slowing down under heavy engine braking. When I say slowing down faster, they aren't actually traveling faster b/c the cam chain keeps them traveling at the same speed, but their momentum/spring force/compression force or whatever is causing them to put tension on the chain in some direction.
At constant speed is there any energy (and thereby a load) being sent from the counter shaft sprocket (also known as the drive sprocket) to the rear wheel sprocket (also known as the driven sprocket)?
At full throttle acceleration, is the force being applied by the chain (thereby placing load on it) between the 2 sprockets which would causes the rear wheel to accelerate or is some outside force (say the road) causing the 2 sprockets to spin at the same speed.
On Deceleration, the same question but in reverse does the countershaft force (through the chain) the rear sprocket to slow down or is it because the wheel is in contact with the road the force that makes the rear wheel slow down?
If it is an outside force, like the road, wouldn't the rate a deceleration be the same if you just pulled the clutch in and coasted?
If it is not an outside force then would an engine that has high "engine braking" put more or less load on the chain while slowing the rear wheel?
Now if you change a few terms around.... countershaft sprocket for crank sprocket. Rear wheel sprocket for cam sprocket and the road for the valve train and you might see why I have the opinion that I do.
Then there would be the question of why do you need a tensioner, the rear wheel doesn't have one??
That can be answered by it really doesn't matter if the drive & driven sprocket, on the finally drive, go out of phase a bit. The cam chain must stay in phase (with a +\- of a degree or so) in order to keep the cam timing correct. Let the timing drift or fluctuate and not only will the engine run poorly, engine damage can and will occur.
The other thing that makes me wonder is if there is no loads being placed on the CCT what would make the ratchet teeth wear and get rounded. If there is just a constant load how could that happen, just poor metal that melts on its own over time?
Last edited by 8541Hawk; 05-10-2012 at 10:05 AM.
05-10-2012, 10:24 AM
#51
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Oh snap, that's did it for me! So engine braking simply puts force in the opposite direction on the crank sprocket.
And doing this quickly would put more load on the CCT quickly as you were talking about earlier.
Which would also give clues to this question:
In terms of immediate tension on the CCT, slamming the throttle shut seems to be worse. If closed slowly, the tension on the CCT isn't as "snappy" and the load is more easily taken up by the CCT. If we're talking about cruising around a corner or coming to a stop or gas mileage or name your variable I don't know which is worse, but in terms of this discussion slamming the throttle shut seems worse to me.
Also, I think Tweety was saying that cruising to a stop in gear (not cutting to idle) saved him because the tension on the chain was consistent rather than just slapping around like it would at idle. Letting it slap around would cause it to jump teeth and then the typical CCT failure valve timing crunches would follow.
And doing this quickly would put more load on the CCT quickly as you were talking about earlier.
Which would also give clues to this question:
Also, I think Tweety was saying that cruising to a stop in gear (not cutting to idle) saved him because the tension on the chain was consistent rather than just slapping around like it would at idle. Letting it slap around would cause it to jump teeth and then the typical CCT failure valve timing crunches would follow.
05-10-2012, 10:43 AM
#52
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Oh snap, that's did it for me! So engine braking simply puts force in the opposite direction on the crank sprocket.
And doing this quickly would put more load on the CCT quickly as you were talking about earlier.
Which would also give clues to this question:
In terms of immediate tension on the CCT, slamming the throttle shut seems to be worse. If closed slowly, the tension on the CCT isn't as "snappy" and the load is more easily taken up by the CCT. If we're talking about cruising around a corner or coming to a stop or gas mileage or name your variable I don't know which is worse, but in terms of this discussion slamming the throttle shut seems worse to me.
Also, I think Tweety was saying that cruising to a stop in gear (not cutting to idle) saved him because the tension on the chain was consistent rather than just slapping around like it would at idle. Letting it slap around would cause it to jump teeth and then the typical CCT failure valve timing crunches would follow.
And doing this quickly would put more load on the CCT quickly as you were talking about earlier.
Which would also give clues to this question:
In terms of immediate tension on the CCT, slamming the throttle shut seems to be worse. If closed slowly, the tension on the CCT isn't as "snappy" and the load is more easily taken up by the CCT. If we're talking about cruising around a corner or coming to a stop or gas mileage or name your variable I don't know which is worse, but in terms of this discussion slamming the throttle shut seems worse to me.
Also, I think Tweety was saying that cruising to a stop in gear (not cutting to idle) saved him because the tension on the chain was consistent rather than just slapping around like it would at idle. Letting it slap around would cause it to jump teeth and then the typical CCT failure valve timing crunches would follow.
Last edited by Tweety; 05-10-2012 at 10:47 AM.
05-10-2012, 11:19 AM
#53
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I thought the timing crank, just by turning the chain, is putting more load on one side of the chain than the other... it pulls the chain, not pushes it, right? Not that it "cares" so to speak as it is designed to do this, but the tension is there. This would also make sense to me b/c the slack is taken up on the opposite side of the CCT, meaning that there will be less pressure on the tensioner... the crank is pushing the slack into it and pulling the chain tight on the other side.
This is 100% correct
Where is the force on the cam chain when you're decelerating? There's no possible way everything is just spinning in there on it's own accord at the exact speed that the bike is slowing down. So is the crank slowing the rest of the components down (this was an assumption that I made before, although now I can't figure out why I made it), or are the cam lobes/ valve spring combos slowing down faster? One of the two has to be making the initiative, because the bike slows down faster than if you were to just let it coast. Unless there is some other factor that I'm not thinking of...
Where is the force on the cam chain when you're decelerating? There's no possible way everything is just spinning in there on it's own accord at the exact speed that the bike is slowing down. So is the crank slowing the rest of the components down (this was an assumption that I made before, although now I can't figure out why I made it), or are the cam lobes/ valve spring combos slowing down faster? One of the two has to be making the initiative, because the bike slows down faster than if you were to just let it coast. Unless there is some other factor that I'm not thinking of...
I’ve said before that there isn’t enough inertia in the cams to overcome the valve springs pushing back at them. Let me put it another way. There is a load on the cams that would normally slow them down much faster than the crank could. So the cam chain is always pulling the cams forward. It is never holding them back with the exception of when the valves are closing and pushing the cam lobe up. Throttle position is irrelevant.
This is a completely different system with completely different loads. In this system you have the weight and inertia of the bike moving forward overcoming any load on the tire. So yes here the drive transfers from the countershaft sprocket to the rear sprocket. This isn’t the case in the cam chain system. The load is always greater on the cams which would slow them down faster than the rest of the engine would slow down. So the load on the chain is always on the drive side
Now if you change a few terms around.... countershaft sprocket for crank sprocket. Rear wheel sprocket for cam sprocket and the road for the valve train and you might see why I have the opinion that I do. Again you can’t just change them around because the loads are applied differently between the two. The cam shafts are very small with not very much weight or inertia so the force of the springs will overcome this very easily. The weight of the bike, the rider and it’s speeds has a HUGE amount of inertia to continue driving the rear sprocket.
Then there would be the question of why do you need a tensioner, the rear wheel doesn't have one?? The rear wheel most certainly does have a tensioner. IT’s a manual one that you adjust by moving the rear wheel for and aft to put the proper tension, or slack, in the chain.
The other thing that makes me wonder is if there is no loads being placed on the CCT what would make the ratchet teeth wear and get rounded. If there is just a constant load how could that happen, just poor metal that melts on its own over time?
Now if you change a few terms around.... countershaft sprocket for crank sprocket. Rear wheel sprocket for cam sprocket and the road for the valve train and you might see why I have the opinion that I do. Again you can’t just change them around because the loads are applied differently between the two. The cam shafts are very small with not very much weight or inertia so the force of the springs will overcome this very easily. The weight of the bike, the rider and it’s speeds has a HUGE amount of inertia to continue driving the rear sprocket.
Then there would be the question of why do you need a tensioner, the rear wheel doesn't have one?? The rear wheel most certainly does have a tensioner. IT’s a manual one that you adjust by moving the rear wheel for and aft to put the proper tension, or slack, in the chain.
The other thing that makes me wonder is if there is no loads being placed on the CCT what would make the ratchet teeth wear and get rounded. If there is just a constant load how could that happen, just poor metal that melts on its own over time?
There obviously is load on the CCT. As the system rotates it needs to keep the slack tight. Also as mentioned when the valve springs are pushing back at the lobe while closing it’s trying to push the cam up and this is the only real time the chain is holding the cams back. This is also a very likely reason the teeth in the ratchet mechanism get worn. On an inline 4 you’ve got 4 sets of valves being operated. While one set is opening you have another set closing. This will offset the forces of the closing valves forcing the cam forward as there will be others trying to push the cam the other direction while they are being opened. This is also why on an inline four to replace the tensioner you just pull the old one out and put the new one in and you don’t have to worry about the cam jumping teeth. So on our bikes you’ve got a single set of valves pushing on each cam so they get the full brunt of this force trying to push the cam up. This would put a constant chattering force, for lack of a better term, in the chain and on the tensioner that an inline four wouldn’t have, and most likely the culprit of why there is an actual service interval when the CCT’s should be changed on our bikes when there isn’t one on an inline four.
That would be the case IF the loads were similar but they aren’t so it’s not. (see above)
Hawk so are you not going to answer my question? Are you avoiding it or did you just miss it?
05-10-2012, 11:49 AM
#54
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There is a load on the cams that would normally slow them down much faster than the crank could. So the cam chain is always pulling the cams forward. It is never holding them back with the exception of when the valves are closing and pushing the cam lobe up. Throttle position is irrelevant.
05-10-2012, 12:09 PM
#55
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LOL! 7 it may help or hurt. Sounded like from his post that... well... he may have had to much already! LOL!
Let's add another portion to this that noone has mentioned. How much pressure is on the valve springs? I looked in the manual and it just gives spring lenght but no actual seat pressure. I'm going to throw out a wild guess and say bare minimum somewhere in the nighborhood of 50-60 lbs while the valve is on the seat and probably closer to 150-160lbs at full lift. You've also got two valves being opened at the same time so double those numbers. So there is say 100-120lbs of force being applied to each cam as it starts to lift the vlave and that pressure goes up to say 300+ lbs as the valves reach full lift. Now you have a cam that weighs what, a couple pounds tops? See where I'm going here? And what I've been saying? Nowhere near enough inertia to overcome that kind of pressue. Now if the Cams were say 20-30 lbs or more then yeah. They'd blow those valves open no problem and the cam chain would need to be slowing them down! We'd also need a MUCH larger chain!
Let's add another portion to this that noone has mentioned. How much pressure is on the valve springs? I looked in the manual and it just gives spring lenght but no actual seat pressure. I'm going to throw out a wild guess and say bare minimum somewhere in the nighborhood of 50-60 lbs while the valve is on the seat and probably closer to 150-160lbs at full lift. You've also got two valves being opened at the same time so double those numbers. So there is say 100-120lbs of force being applied to each cam as it starts to lift the vlave and that pressure goes up to say 300+ lbs as the valves reach full lift. Now you have a cam that weighs what, a couple pounds tops? See where I'm going here? And what I've been saying? Nowhere near enough inertia to overcome that kind of pressue. Now if the Cams were say 20-30 lbs or more then yeah. They'd blow those valves open no problem and the cam chain would need to be slowing them down! We'd also need a MUCH larger chain!
05-10-2012, 12:27 PM
#56
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Hey now, I didn't mis-spell a single word, and my paragraph was coherent, therefore the inertia being forced upon my brain valves was not enough to slow down my cognitive thinking sprockets, whick tells ne that there was not enough force being applied to my lucidity tensioner by my chain of Red Stripe.
What I failed the think about was that the cam sprockets are dependant on the chain to spin, so my theory is ****.
What I failed the think about was that the cam sprockets are dependant on the chain to spin, so my theory is ****.
05-10-2012, 12:33 PM
#57
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The cush drive in the rear wheel.
It is in place to take the shock loads from the chain when the load transverse from one side of the chain to the other. Not just take the shock load when the bike is placed into gear from a stand still.
What happens if you remove the cush drive. The most common failure would be a transmission gear.
While some SM bikes can and do get away without running a cush drive, they also are much lighter and have no where near 100hp.
So if there is no load, what would cause a transmission gear to shed teeth? Would you think a transmission gear is stronger or weaker than a CCT assembly?
As for the comment of there is a tensioner on the drive chain, this is totally incorrect. By definition a "tensioner" keeps constant tension on the chain.
If you had a tensioner on the drive train why is the technique of maintenance throttle taught. Why would someone like Dave Moss in the the link posted to his "On the Throttle" program Dave Moss Unsprung: Tire Wear, how to "see" what your tire is telling you in terms of wear patterns that can easily be recognized and then attended to. Th... make the statement of you need maintenance throttle through a corner to keep tension on the drive side of the chain? I guess he doesn't know how the stuff works either.
So no matter the loads a chain drive is a chain drive.
The drive sprocket controls the speed of the driven sprocket. When the drive sprocket accelerates the driven sprockets accelerate. When the drive sprocket decelerates, the driven sprockets decelerate.
If an outside force is in control of the speed of the driven sprockets how is it possible to keep them within 1-2 degrees of crank rotation in all situations?
Thanks for bringing some humor to the thread AJA!
05-10-2012, 12:41 PM
#59
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By what GTS said a couple of posts ago, Ducati's wouldn't ever have even small tension in the opposite direction b/c of the way their desmodromic valves work...?
...I looked it up, I couldn't remember what it was called...
So by what you're saying, if you were to run the motor, then close the throttle quickly somehow take the cam chain off instantaneously (aside from that being something only Tony Stark could figure out how to do), the cams would stop moving faster than the crank?
...I looked it up, I couldn't remember what it was called...
So by what you're saying, if you were to run the motor, then close the throttle quickly somehow take the cam chain off instantaneously (aside from that being something only Tony Stark could figure out how to do), the cams would stop moving faster than the crank?
05-10-2012, 01:02 PM
#60
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So yes while the valves are opening, under decel conditions there is a load on the drive side of the chain.
Conversely when the valves close, the load is now on the opposite side of the chain (or tensioner side) as it must be to control the speed of the camshaft in relation to the speed of the crank.
So saying the load is always on the drive side of the chain is incorrect.
