Lacking Power
07-01-2009, 08:40 PM
#1
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Squid
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Lacking Power
I recently just bought a 2001 Hawk with 9500 miles. One of my friends had one and said he could pull the front end up with little effort. I was playing around on a dead end road today and found that I could not get the front end off the ground. I previously had a ZX6R which a few cracks on the throttle would pick the front end right up. Even trying this I could not get the front end up. The bike really doesn't seem to run bad, but compared to my old ZX6R it does seem kind of slow. I recently changed the plugs, which looked okay. Any suggestions or thoughts?
07-01-2009, 09:01 PM
#4
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Location: Sioux Falls, SD
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If you can't get a Superhawk up on the back tire in first gear you either have some carb/power issues or some serious technique problems.
I found it easy to either crack it wide open or slightly clutch it at about 4k. I haven't tried 2nd gear power wheelies since my jet kit install. Once I reseal the forks and remount the front end I'm looking forward to them.
I found it easy to either crack it wide open or slightly clutch it at about 4k. I haven't tried 2nd gear power wheelies since my jet kit install. Once I reseal the forks and remount the front end I'm looking forward to them.
07-01-2009, 09:05 PM
#5
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Squid
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I am leaning more towards power issues as I never had an issue getting my ZX6R to come up. Is it quite noticeable if the bike isn't running right on both cylinders? The bike still seems to accelerate quickly.
07-01-2009, 09:46 PM
#6
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Squid
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I forgot to mention 2 other things, one I live in Colorado so altitude may play a factor, and second, I noticed my chain has kinks(looks like links are tight). Do you think any of these would cut the power that much?
07-02-2009, 12:30 AM
#7
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Another thing to note since you compare to a ZX6R... Where the ZX6R is strong the VTR has run out of revs... Start low and you should have enough torque to make a backflip in both 1'st and 2'nd...
Yeah kinking the chain robs a lot of power... But I'd look it through and see if there are other issues too... Check the airfilter and do a carb sync to start with...
As for jetting... stock should be OK'ish... Not ideal, but good enough... Altough if someone has been in there that doesn't know his way around it can play a major factor... Ask Hawkrider for jetting advice on diff altitude... I'm just a trial-n-error kinda tuner...
Yeah kinking the chain robs a lot of power... But I'd look it through and see if there are other issues too... Check the airfilter and do a carb sync to start with...
As for jetting... stock should be OK'ish... Not ideal, but good enough... Altough if someone has been in there that doesn't know his way around it can play a major factor... Ask Hawkrider for jetting advice on diff altitude... I'm just a trial-n-error kinda tuner...
07-02-2009, 12:39 AM
#8
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The Super Hawk will easily flip over backwards in first gear just rolling on the throttle. This isn't something that's hard to find or takes skill or timing to do. Grab a handful of throttle in first gear and she will loop. If it doesn't want to do that something is wrong.
07-02-2009, 02:52 AM
#10
I could ride in
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The Super Hawk will easily flip over backwards in first gear just rolling on the throttle. This isn't something that's hard to find or takes skill or timing to do. Grab a handful of throttle in first gear and she will loop. If it doesn't want to do that something is wrong.
+1
07-02-2009, 03:39 AM
#11
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07-02-2009, 04:00 AM
#12
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Yea, mine won't wheelie worth a damn and hasn't since I bought her just under three years ago. Thats why she's torn apart for the LAST TIME right now out in the garage.
The previous owner had the general mods done (K&N, DynoJet kit (190/185-5th clip), and high mount Jardine's (51.5mm interior diameter tips)) and when I was still being introduced to the bike, before I bought it I blipped the throttle a little and I was skeptical about its response. He said "just go back to stock and it will be fine" - and it DEFINATELY was not.
So my only current lead is that there is an air leak somewhere in the front cylinder area. I know this because I can get the carbs synced at idle, but when I pull it out of idle and up to 3krpm they completely fall out of sync.
I'm at the point now when I have a minute and the homework is aside, I'm going to attempt my first leak down check, and do a timing light check as well. I spent the other week scratching my head as to why the timing marks wouldn't line up right on the cams compared to the timing mark on the flywheel and vice versa when properly aligned.
The thing just doesn't run right and I've been "getting by" riding it like this for almost three years and am sick of it. So its gonna sit there until I start coming across some evidence on whats wrong.
For my knowledge do a carb' sync and pull the throttle open and hold it at 3krpm and see if the carbs are still sync'd. I bring up the 3krpm number from my 1984 CB650sc Honda Nighthawk manual back in the day; it said when doing the carb sync to "confirm at 3krpm" after doing the carb sync but I don't think it says anything like that in our manaul.
If you've got a good carb sync' going, do a pilot screw, and TPS adjustment next.
Another note is - I don't know what a "good spark" is supposed to look like when doing a basic spark test on a plug, but I replaced mine when I got the bike a couple years ago in hopes of shimmy'ing my way along in fixing this "weak motor" ride I'd just got. ...And... ...I just wasn't impressed with the intensity of the spark that was taking place when I grounded out the electrode to the engine. So thats another clue for my puzzle I guess.
Anyhoo'.
The previous owner had the general mods done (K&N, DynoJet kit (190/185-5th clip), and high mount Jardine's (51.5mm interior diameter tips)) and when I was still being introduced to the bike, before I bought it I blipped the throttle a little and I was skeptical about its response. He said "just go back to stock and it will be fine" - and it DEFINATELY was not.
So my only current lead is that there is an air leak somewhere in the front cylinder area. I know this because I can get the carbs synced at idle, but when I pull it out of idle and up to 3krpm they completely fall out of sync.
I'm at the point now when I have a minute and the homework is aside, I'm going to attempt my first leak down check, and do a timing light check as well. I spent the other week scratching my head as to why the timing marks wouldn't line up right on the cams compared to the timing mark on the flywheel and vice versa when properly aligned.
The thing just doesn't run right and I've been "getting by" riding it like this for almost three years and am sick of it. So its gonna sit there until I start coming across some evidence on whats wrong.
For my knowledge do a carb' sync and pull the throttle open and hold it at 3krpm and see if the carbs are still sync'd. I bring up the 3krpm number from my 1984 CB650sc Honda Nighthawk manual back in the day; it said when doing the carb sync to "confirm at 3krpm" after doing the carb sync but I don't think it says anything like that in our manaul.
If you've got a good carb sync' going, do a pilot screw, and TPS adjustment next.
Another note is - I don't know what a "good spark" is supposed to look like when doing a basic spark test on a plug, but I replaced mine when I got the bike a couple years ago in hopes of shimmy'ing my way along in fixing this "weak motor" ride I'd just got. ...And... ...I just wasn't impressed with the intensity of the spark that was taking place when I grounded out the electrode to the engine. So thats another clue for my puzzle I guess.
Anyhoo'.
Last edited by Spaz'; 07-02-2009 at 04:04 AM.
07-02-2009, 02:33 PM
#13
I don't need any Meds
Superstock
Join Date: May 2009
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Yea, mine won't wheelie worth a damn and hasn't since I bought her just under three years ago. Thats why she's torn apart for the LAST TIME right now out in the garage.
The previous owner had the general mods done (K&N, DynoJet kit (190/185-5th clip), and high mount Jardine's (51.5mm interior diameter tips)) and when I was still being introduced to the bike, before I bought it I blipped the throttle a little and I was skeptical about its response. He said "just go back to stock and it will be fine" - and it DEFINATELY was not.
So my only current lead is that there is an air leak somewhere in the front cylinder area. I know this because I can get the carbs synced at idle, but when I pull it out of idle and up to 3krpm they completely fall out of sync.
I'm at the point now when I have a minute and the homework is aside, I'm going to attempt my first leak down check, and do a timing light check as well. I spent the other week scratching my head as to why the timing marks wouldn't line up right on the cams compared to the timing mark on the flywheel and vice versa when properly aligned.
The thing just doesn't run right and I've been "getting by" riding it like this for almost three years and am sick of it. So its gonna sit there until I start coming across some evidence on whats wrong.
For my knowledge do a carb' sync and pull the throttle open and hold it at 3krpm and see if the carbs are still sync'd. I bring up the 3krpm number from my 1984 CB650sc Honda Nighthawk manual back in the day; it said when doing the carb sync to "confirm at 3krpm" after doing the carb sync but I don't think it says anything like that in our manaul.
If you've got a good carb sync' going, do a pilot screw, and TPS adjustment next.
Another note is - I don't know what a "good spark" is supposed to look like when doing a basic spark test on a plug, but I replaced mine when I got the bike a couple years ago in hopes of shimmy'ing my way along in fixing this "weak motor" ride I'd just got. ...And... ...I just wasn't impressed with the intensity of the spark that was taking place when I grounded out the electrode to the engine. So thats another clue for my puzzle I guess.
Anyhoo'.
The previous owner had the general mods done (K&N, DynoJet kit (190/185-5th clip), and high mount Jardine's (51.5mm interior diameter tips)) and when I was still being introduced to the bike, before I bought it I blipped the throttle a little and I was skeptical about its response. He said "just go back to stock and it will be fine" - and it DEFINATELY was not.
So my only current lead is that there is an air leak somewhere in the front cylinder area. I know this because I can get the carbs synced at idle, but when I pull it out of idle and up to 3krpm they completely fall out of sync.
I'm at the point now when I have a minute and the homework is aside, I'm going to attempt my first leak down check, and do a timing light check as well. I spent the other week scratching my head as to why the timing marks wouldn't line up right on the cams compared to the timing mark on the flywheel and vice versa when properly aligned.
The thing just doesn't run right and I've been "getting by" riding it like this for almost three years and am sick of it. So its gonna sit there until I start coming across some evidence on whats wrong.
For my knowledge do a carb' sync and pull the throttle open and hold it at 3krpm and see if the carbs are still sync'd. I bring up the 3krpm number from my 1984 CB650sc Honda Nighthawk manual back in the day; it said when doing the carb sync to "confirm at 3krpm" after doing the carb sync but I don't think it says anything like that in our manaul.
If you've got a good carb sync' going, do a pilot screw, and TPS adjustment next.
Another note is - I don't know what a "good spark" is supposed to look like when doing a basic spark test on a plug, but I replaced mine when I got the bike a couple years ago in hopes of shimmy'ing my way along in fixing this "weak motor" ride I'd just got. ...And... ...I just wasn't impressed with the intensity of the spark that was taking place when I grounded out the electrode to the engine. So thats another clue for my puzzle I guess.
Anyhoo'.
I can even be rolling along at about 50 in 3rd or 4th roll it on and it is off the ground. not like straight up and down, but the front is coming off and i got alot more rpm to go.
like some one else said the one i am riding could be flipped over back wards pretty easy.
Hope you find the issue.
best of luck.
50
07-02-2009, 03:29 PM
#14
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You WILL have some difference between idle and 3k on the carb sync, even when everything's perfect. There should be no more than 1 or 2 inches of mercury difference. If that little bit bothers you then adjust sync halfway between.
07-02-2009, 05:21 PM
#17
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1-2" difference in mercury...
Thanks for the notes guys. I'll note that 1-2" is expected - thank you Greg. I never knew such a tolarance was permitted (And don't know what those values convert to when considering 498cc's per cylinder - maybe I should research this. FYI: Yes, I do use a MotionPro mercury syncronizer (S?)), and I'd say that there was at least that much difference going on when I took the RPM's up to 3k. I'd always thought they were supposed to be just about spot on after sync'ing at idle.
Maybe I do have an electrical problem of some sort going on. Maybe that weak spark that I saw is something I should be considering. ...Unfortunately to do some of these electrical tests on the hardware one needs Honda's "specialized" equipment, for which I have zero intention of investing at this point in time. I'm just going to have to make due with the tools I have and fiddle some when I have time.
The bike was in a low speed drop on its left side at >15-20mph. Or so the previous owner told me. :\ Maybe this boink'd the electronics some.
I'd also considered since there is no real fuel filter on this bike that something has clogged one or two of the pipings in either of the carbs. I got me my 1 gallon can of ChemTool B-12 to put to use for that stuff. I know that the SeaFoam is the next step up from what I hear. I also have my shop air compressor to utilize in airgunning out the pipings. But those holes where the throttle body rests directly over... ...them' are tiny - I've got a welders cleaning tip kit that I can use (Yes, I know about having to use them gently). ...I dunno.
I gotta cruz' for a bit. We're startin' to fry here in my area at about 94F or so and have to get the AC's in the windows and push on my homework some. I'm totally around...
Spaz'
Maybe I do have an electrical problem of some sort going on. Maybe that weak spark that I saw is something I should be considering. ...Unfortunately to do some of these electrical tests on the hardware one needs Honda's "specialized" equipment, for which I have zero intention of investing at this point in time. I'm just going to have to make due with the tools I have and fiddle some when I have time.
The bike was in a low speed drop on its left side at >15-20mph. Or so the previous owner told me. :\ Maybe this boink'd the electronics some.
I'd also considered since there is no real fuel filter on this bike that something has clogged one or two of the pipings in either of the carbs. I got me my 1 gallon can of ChemTool B-12 to put to use for that stuff. I know that the SeaFoam is the next step up from what I hear. I also have my shop air compressor to utilize in airgunning out the pipings. But those holes where the throttle body rests directly over... ...them' are tiny - I've got a welders cleaning tip kit that I can use (Yes, I know about having to use them gently). ...I dunno.
I gotta cruz' for a bit. We're startin' to fry here in my area at about 94F or so and have to get the AC's in the windows and push on my homework some. I'm totally around...
Spaz'
07-02-2009, 06:10 PM
#18
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Think about what you're measuring here. Vacuum at the intake. What affects vacuum? Well, here's a list:
- air leaks at the carbs
- cylinder and ring wear
- valve wear and/or clearances
- cam timing
- carb settings and tolerances downstream of the butterflies
Notice no electrical gremlins in this list. Now, what differs as you raise rpm? Could be any one except cam timing I'd think.
- air leaks at the carbs
- cylinder and ring wear
- valve wear and/or clearances
- cam timing
- carb settings and tolerances downstream of the butterflies
Notice no electrical gremlins in this list. Now, what differs as you raise rpm? Could be any one except cam timing I'd think.
07-02-2009, 06:43 PM
#19
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SuperBike
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Interestingly, I've had the same problem. Having never ridden another SHawk, I couldn't tell if it was as fast as the next one. It sure didn't seem as quick or wheelie happy as my '91 GSXR 1100. I had adjusted the needles when I got the bike to richen it up a bit. I didn't have any backfiring, so I figured I was close to what it should be. Then I started reading here about the characteristics and started thinking something was wrong. Pulled the carbs and the main jets were Dynojet 175 on the front and 180 on the rear. My bike has a K&N filter and Micron exhaust. I've changed the mains to 185F and 190R with the clip on the 5th groove(from the flat end) plus a washer. This has really improved the performance of the bike. I'm still dickering with the slow jet, seems a little rich. All this to say, if you have some mods on your bike, check your jets when you pull the carbs.
07-02-2009, 07:48 PM
#20
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Service manual spec for carb sync is .8 column inches of mercury. That's about 11 inches of water, a bit more for something like ATF.
I filled my home made carb sync tool with ATF and have always been able to get the columns within about a half inch of each other at idle. That's equal to about 1/20 of an inch of mercury.
The difference between how the bike runs with carbs synced that closely vs. 8/10 column inches of mercury equivalent or more is very noticeable.
At least on my VTR it isn't hard to do and results in way less vibration and way better throttle response than when the sync is just barely within spec.
I filled my home made carb sync tool with ATF and have always been able to get the columns within about a half inch of each other at idle. That's equal to about 1/20 of an inch of mercury.
The difference between how the bike runs with carbs synced that closely vs. 8/10 column inches of mercury equivalent or more is very noticeable.
At least on my VTR it isn't hard to do and results in way less vibration and way better throttle response than when the sync is just barely within spec.
07-05-2009, 06:33 AM
#21
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Thank you guys
Thanks guys for the help. My schooling is taking up a large portion of my time and its been hot as sin up here the last few days. So there ain't no goin' in the garage for me for a bit.
I promise to get back with my findings. I sincerely appreciate the guidance!
I promise to get back with my findings. I sincerely appreciate the guidance!
07-05-2009, 02:53 PM
#22
I don't need any Meds
Superstock
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here is a link http://www.superhawk996.net/Honda_VT...ice_Manual.pdf
Last edited by 5150; 07-05-2009 at 03:20 PM. Reason: adding link for Shawk Manual
07-06-2009, 05:48 PM
#25
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Squid
Join Date: Apr 2009
Location: Oshawa, Ontario
Posts: 64
Unfortunately my mechanic is gonna have to look at my 2000 SH cause first gear will wheelie, at around 5 or 6 thousand RPM pretty good but not flip worthy and definitly not in second. Can't wait for this beast to rip my arms out of socket
07-19-2009, 05:19 AM
#27
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Alright guys. As of the other day, she is put back together so that I can do a proper compression test, with the engine warm, and I'll see how far I can get with the leak down tester.
I don't know when I'll have time to get around to doing this, but I will be back.
I don't know when I'll have time to get around to doing this, but I will be back.
09-13-2009, 06:30 PM
#28
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Compression test results
Right. I've returned. I took the time out today to do a compression test and a half *** leak down test for what I could do with what I had. I didn't even think about it until after but I should have just worked directly off of the >150psi regulator on the compressor tank. During this leak down test I used the US General leak down tester I got from Harbor Freight - of which I already diddled up the percentage gauge. So I was just in to this for the audible part of it all.
The regulator on this leak down tester only went up to 100psi; I know there is supposed to be a limited percentage of leakage but I wasn't able to isolate that during this test. None the less, before we get any further my compression test that was done (With the spark plugs removed from each cylinder and testing each cylinder one at a time - and the engine having just been warmed up to about 202F from a cruz' downtown.) came out somewhere around 90psi on the front and about 75psi on the rear. I know the compression is supposed to be 165psi and tested when the engine is warm (Has been run to OT prior to compression testing).
So really the results here do make me sick, but at least I have something to work off of apparently. During the leak down test the only real place I was able to isolate a significant amount of airflow noise was through the crankcase (Listening through the oil fill hole.). With my mechanics stethoscope I didn't really hear too much coming through the intake or exhaust valve area. This was all done at about 70psi. I know it should have been taken higher, but perhaps I should try to work off of the compressor tank regulator instead to push it higher. Really, I was kind of sold on the rings being bad or worn or whatever - I have 29.8k miles on the engine, and I purchased it with ~16.5k.
What’s weird though is it doesn't really burn oil. I don't push her to hard and rarely try to enjoy an aircraft carrier catapult takeoff as much as I'd like to cause I know it runs like crap. However when I went on my first ride outside of town when I first got it three years ago, I went up around the SE side of Mt. St. Helens, and came back and the !#%$!#$%^ had burned well over half a quart of oil - maybe even almost a full quart. I just dreaded to myself what I'd just come home with. ...However, ever since then - she never ever really needs to be topped off with oil ever during its 3k mile oil change intervals. It happens, but not like that particular ride I took during the first week or so of ownership of the bike. In addition, just by my looking at it (And I have no clue on what or how to judge it all.) the oil, when it is drained looks just fine. No major carbon deposit buildup etc. from combustion gasses passing by the rings and into the crankcase. My gas mileage around town has been at about 33-34mpg the last week or so. I dunno what it is on the highway. I think it was about 37-39mpg perhaps when I was outside of town last week.
When it came to me doing the carb’ sync again last month the mercury intake reading averaged between both cylinders was just at about 22 inches of mercury (If I’m reading it scale correctly – see the attached pic’).
Quoting Hawkrider: “Think about what you're measuring here. Vacuum at the intake. What affects vacuum? Well, here's a list:
- air leaks at the carbs
- cylinder and ring wear
- valve wear and/or clearances
- cam timing
- carb settings and tolerances downstream of the butterflies”
I’m putting aside the possible air leaks at the carbs for the moment.
Cylinder and ring wear is on my mind. While putting the bike back together this one particular night (almost a month and a half ago) and had the carbs apart and cleaning them out, I put a few CC’s of Marvel’s Mystery Oil down in each cylinder and let it sit for a few hours. I didn’t have time to do an “overnight” job with this ring soaking application but shimmied the crankshaft back and forth every 45 minutes or so in hopes to dislodge a possibly sticking ring.
Valve wear and/or clearance is on my mind to. When I got this bike at ~16.5k it apparently (I say apparently because God knows what the previous owner did to this thing – I found several things wrong with it when I first started chasing the problems I’m having a couple years ago.) did not have the valve last checked. I just came home with a Bike Master feeler gauge set and hopefully I can figure out the right combinations of gauges to use in order to see what and if I need any new shims installed. ***Do any of you know a manufacturer who makes feeler gauges made custom for measuring out valve lash for our bikes properly? If there is anything that needs to be adjusted, it’s going to be a long shot I think. This feeler gauge set is very generalized and I want to go into the cam’ area on this bike only one more time in the next 16k miles I put on it for heaven’s sake…
I’m putting the possibility of a cam’ timing error off for the moment. I just did an ignition timing mark check with my new timing light with an advance adjust and don’t know how to use it exactly with my Factory Pro four degree ignition advance installed. When the advance on the timing light was set to zero, the “F mark” (Not the “F” – the F “mark”) was off (Sitting higher than the mark on the crank case cover. When I set the advance on the timing light to four, it got a little closer. In order to get it to be right on the mark I had to turn the advance on the light all the way up to eight I think. …This was all done with the inductive clamp working off of the front cylinder. This is an ’01 Superhawk with the supposedly upgraded CCT springs. Upon reassembly of the camshaft stuff I had apart the other month, I adjusted the CCT springs by way of letting the tension determine the best amount of force to be used; I did no tightening of them on my own.
Carb settings and tolerances downstream of the butterflies: Everything has been put back to dead stock settings on everything. I even have the PAIR installed on it. I’ve had the carbs torn apart to the best of my ability and pushed compressed air through each of the holes and nothing has come out. I even used ChemTool B12 and Sea Foam dribbled down the tiny little holes at the throttle plate for the very best that I could with a medicine dropper or something. I was only able to let it sit for an hour or so cause I was on my way to putting the bike back together so I could do the “engine at OT compression test” – of which I did a few hours ago.
So… …now, I’m at the point where I am considering going over to see a gentleman I was recommended to over in Portland, (Oregon) by the name of Ron Hopkins (http://www.ronsperformance.net/). (Any of you in the area know of whom this is and give me some customer feedback?) I was talking with the manager of the Portland Cycle Gear, and a Superhawk owner the other day and they both recommended me to him. My intent is to have a dyno run made on this thing and see if my compression test results were false (I know God made me perfect but need computerized dyno testers to prove me otherwise. :P ) and if there is any additional data I can acquire from such a run.
I know this has just been a huge super’saurous posting, but there are several of us out here who have Superhawks that just aren’t performing like their supposed to. I’ll try and do a leak down test at a higher pressure another day soon. So I hope some of this leads us to a breakthrough. As usual, thank you everyone for your help and input.
-Spaz
The regulator on this leak down tester only went up to 100psi; I know there is supposed to be a limited percentage of leakage but I wasn't able to isolate that during this test. None the less, before we get any further my compression test that was done (With the spark plugs removed from each cylinder and testing each cylinder one at a time - and the engine having just been warmed up to about 202F from a cruz' downtown.) came out somewhere around 90psi on the front and about 75psi on the rear. I know the compression is supposed to be 165psi and tested when the engine is warm (Has been run to OT prior to compression testing).
So really the results here do make me sick, but at least I have something to work off of apparently. During the leak down test the only real place I was able to isolate a significant amount of airflow noise was through the crankcase (Listening through the oil fill hole.). With my mechanics stethoscope I didn't really hear too much coming through the intake or exhaust valve area. This was all done at about 70psi. I know it should have been taken higher, but perhaps I should try to work off of the compressor tank regulator instead to push it higher. Really, I was kind of sold on the rings being bad or worn or whatever - I have 29.8k miles on the engine, and I purchased it with ~16.5k.
What’s weird though is it doesn't really burn oil. I don't push her to hard and rarely try to enjoy an aircraft carrier catapult takeoff as much as I'd like to cause I know it runs like crap. However when I went on my first ride outside of town when I first got it three years ago, I went up around the SE side of Mt. St. Helens, and came back and the !#%$!#$%^ had burned well over half a quart of oil - maybe even almost a full quart. I just dreaded to myself what I'd just come home with. ...However, ever since then - she never ever really needs to be topped off with oil ever during its 3k mile oil change intervals. It happens, but not like that particular ride I took during the first week or so of ownership of the bike. In addition, just by my looking at it (And I have no clue on what or how to judge it all.) the oil, when it is drained looks just fine. No major carbon deposit buildup etc. from combustion gasses passing by the rings and into the crankcase. My gas mileage around town has been at about 33-34mpg the last week or so. I dunno what it is on the highway. I think it was about 37-39mpg perhaps when I was outside of town last week.
When it came to me doing the carb’ sync again last month the mercury intake reading averaged between both cylinders was just at about 22 inches of mercury (If I’m reading it scale correctly – see the attached pic’).
Quoting Hawkrider: “Think about what you're measuring here. Vacuum at the intake. What affects vacuum? Well, here's a list:
- air leaks at the carbs
- cylinder and ring wear
- valve wear and/or clearances
- cam timing
- carb settings and tolerances downstream of the butterflies”
I’m putting aside the possible air leaks at the carbs for the moment.
Cylinder and ring wear is on my mind. While putting the bike back together this one particular night (almost a month and a half ago) and had the carbs apart and cleaning them out, I put a few CC’s of Marvel’s Mystery Oil down in each cylinder and let it sit for a few hours. I didn’t have time to do an “overnight” job with this ring soaking application but shimmied the crankshaft back and forth every 45 minutes or so in hopes to dislodge a possibly sticking ring.
Valve wear and/or clearance is on my mind to. When I got this bike at ~16.5k it apparently (I say apparently because God knows what the previous owner did to this thing – I found several things wrong with it when I first started chasing the problems I’m having a couple years ago.) did not have the valve last checked. I just came home with a Bike Master feeler gauge set and hopefully I can figure out the right combinations of gauges to use in order to see what and if I need any new shims installed. ***Do any of you know a manufacturer who makes feeler gauges made custom for measuring out valve lash for our bikes properly? If there is anything that needs to be adjusted, it’s going to be a long shot I think. This feeler gauge set is very generalized and I want to go into the cam’ area on this bike only one more time in the next 16k miles I put on it for heaven’s sake…
I’m putting the possibility of a cam’ timing error off for the moment. I just did an ignition timing mark check with my new timing light with an advance adjust and don’t know how to use it exactly with my Factory Pro four degree ignition advance installed. When the advance on the timing light was set to zero, the “F mark” (Not the “F” – the F “mark”) was off (Sitting higher than the mark on the crank case cover. When I set the advance on the timing light to four, it got a little closer. In order to get it to be right on the mark I had to turn the advance on the light all the way up to eight I think. …This was all done with the inductive clamp working off of the front cylinder. This is an ’01 Superhawk with the supposedly upgraded CCT springs. Upon reassembly of the camshaft stuff I had apart the other month, I adjusted the CCT springs by way of letting the tension determine the best amount of force to be used; I did no tightening of them on my own.
Carb settings and tolerances downstream of the butterflies: Everything has been put back to dead stock settings on everything. I even have the PAIR installed on it. I’ve had the carbs torn apart to the best of my ability and pushed compressed air through each of the holes and nothing has come out. I even used ChemTool B12 and Sea Foam dribbled down the tiny little holes at the throttle plate for the very best that I could with a medicine dropper or something. I was only able to let it sit for an hour or so cause I was on my way to putting the bike back together so I could do the “engine at OT compression test” – of which I did a few hours ago.
So… …now, I’m at the point where I am considering going over to see a gentleman I was recommended to over in Portland, (Oregon) by the name of Ron Hopkins (http://www.ronsperformance.net/). (Any of you in the area know of whom this is and give me some customer feedback?) I was talking with the manager of the Portland Cycle Gear, and a Superhawk owner the other day and they both recommended me to him. My intent is to have a dyno run made on this thing and see if my compression test results were false (I know God made me perfect but need computerized dyno testers to prove me otherwise. :P ) and if there is any additional data I can acquire from such a run.
I know this has just been a huge super’saurous posting, but there are several of us out here who have Superhawks that just aren’t performing like their supposed to. I’ll try and do a leak down test at a higher pressure another day soon. So I hope some of this leads us to a breakthrough. As usual, thank you everyone for your help and input.
-Spaz
Last edited by Spaz'; 09-13-2009 at 06:35 PM.
09-16-2009, 02:23 PM
#29
Senior Member
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Join Date: Sep 2007
Location: Vancouver, WA
Posts: 153
Hey everyone. I'm sorry, I made a silly mistake while doing my compression test - I didn't have the throttle wide open. So I went back and did it over again, and I also had the carb' diaphrams held open. The compression on each cylinder with the engine coolant temp' reading about 170F (With the engine actually being taken to 208F earlier) is actually:
Front: ~125-130psi
Rear: ~125-130psi
So I'm missing a full 25% compression compared to 165psi. At least the cylinders are balanced. More news to come later...
-Spaz
Front: ~125-130psi
Rear: ~125-130psi
So I'm missing a full 25% compression compared to 165psi. At least the cylinders are balanced. More news to come later...
-Spaz
Last edited by Spaz'; 09-16-2009 at 02:26 PM. Reason: I always forget something. :)
09-18-2009, 09:41 PM
#30
Senior Member
Back Marker
Join Date: Sep 2007
Location: Vancouver, WA
Posts: 153
Well well well, look what I found today...
So I have my reasons for not explaining why I wanted to take apart the fuel petcock today, but I did so, and look what I found (See pics. ...Wait, you can't see the pics. Sorry, the file sizes were to big. ...But it was about an inch long around the rim of the diaphram body.)!!!
This still doesn't justify the loss of compression like I have, and I realized I should have had the opposing carburator diaphram open (Have both open at the same time.) when I did my compression test.
So there is my air leak (At least one of them.). I did a small Scotch tape job on each side to help get me half assed'ly by until my replacement comes to me later next week from the Honda shop. I resync'd the carb's after doing that little McGeyver (S?) job and I'd say it made a small difference for what it's worth.
I was totally not expecting to find that diaphram in the condition it was in though. So anyway, the saga goes on.
This still doesn't justify the loss of compression like I have, and I realized I should have had the opposing carburator diaphram open (Have both open at the same time.) when I did my compression test.
So there is my air leak (At least one of them.). I did a small Scotch tape job on each side to help get me half assed'ly by until my replacement comes to me later next week from the Honda shop. I resync'd the carb's after doing that little McGeyver (S?) job and I'd say it made a small difference for what it's worth.
I was totally not expecting to find that diaphram in the condition it was in though. So anyway, the saga goes on.
