Clunk then cuts off?
02-27-2015, 04:06 PM
#1
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Squid
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Location: Austin, Tx
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Clunk then cuts off?
First post on the forum but i lurked it a lot before making the choice to buy my hawk.
Anyways just got a 2005 Hawk and have run into a little issue with it. While idling it will make a clunk noise then shut off. I found this video on youtube that you can hear the same noise and see the idle drop.
https://www.youtube.com/watch?v=87o1_wEd07E.
If i have my idle set at the 1100 rpm its supposed to be this drop will kill the bike if its higher like this guy it will recover without stalling. It fires right back up and doesnt happen nearly as much as in the video but exact same noise. Any idea what this could be? it sounds a lot like the power cuts out for a second. Also the led backlight on my display flickers a bit at idle. I was thinking possible rectifier? The Idle also hunts a little like swings between 1000 - 1200rpm.
Thanks for any direction you guys can provide im great with cars but this is my first bike in forever.
Anyways just got a 2005 Hawk and have run into a little issue with it. While idling it will make a clunk noise then shut off. I found this video on youtube that you can hear the same noise and see the idle drop.
https://www.youtube.com/watch?v=87o1_wEd07E.
If i have my idle set at the 1100 rpm its supposed to be this drop will kill the bike if its higher like this guy it will recover without stalling. It fires right back up and doesnt happen nearly as much as in the video but exact same noise. Any idea what this could be? it sounds a lot like the power cuts out for a second. Also the led backlight on my display flickers a bit at idle. I was thinking possible rectifier? The Idle also hunts a little like swings between 1000 - 1200rpm.
Thanks for any direction you guys can provide im great with cars but this is my first bike in forever.
02-27-2015, 06:54 PM
#4
Well take off, eh.
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Join Date: Jun 2012
Location: QC, Canada
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Yes. Carbs not being sync'd means they are not working....well...in sync. 
This causes what you see in the video, and, it does cause the engine to die down. Many will neglect syncing the carbs, and just raise idle speed to compensate. IMHO, this is a no no. You are driving around with a motorcycle that is not working properly, and, will vibrate like a Hardley for no reason, reducing power, and comfort.
Make sure you sync at idle, and, also at about 4000rpm.
This causes what you see in the video, and, it does cause the engine to die down. Many will neglect syncing the carbs, and just raise idle speed to compensate. IMHO, this is a no no. You are driving around with a motorcycle that is not working properly, and, will vibrate like a Hardley for no reason, reducing power, and comfort.
Make sure you sync at idle, and, also at about 4000rpm.
02-27-2015, 09:01 PM
#5
Rex Kramer-Thrill Seeker
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I agree, it's a carb issue.
To sync your carbs, there are tools you can readily buy, or there are simple tools you can make for as cheap as a couple bucks. Search the web and there are several different DIY ways. I prefer the "two bottle" method, as this way prevents your sync fluid from getting sucked into the engine if your carbs are way out of sync.
However, since you bring up your Regulator/Rectifier, does your bike still have the stock one?
To sync your carbs, there are tools you can readily buy, or there are simple tools you can make for as cheap as a couple bucks. Search the web and there are several different DIY ways. I prefer the "two bottle" method, as this way prevents your sync fluid from getting sucked into the engine if your carbs are way out of sync.
However, since you bring up your Regulator/Rectifier, does your bike still have the stock one?
02-28-2015, 07:08 AM
#6
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Squid
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no idea just got it last week havent really ridden it other than the drive home because its been so cold. I ordered the brass vac fitting and will probably use the two bottle or the hose method to balance when it comes in. hopefully its something as simple as that.
03-09-2015, 09:10 AM
#11
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idle drop didn't help still just swings idle not steady at all. its a 2005 with 26000 miles on it no idea of previous service history seems to have been taken care of. What type of plugs does this thing have possibly need changed?
03-09-2015, 10:05 AM
#12
Rex Kramer-Thrill Seeker
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Location: Brookfield, WI
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You did this below?
Blip Test
1. Start by warming the bike up to normal operating temperature.
2. Blip the throttle up several thousand RPM's or up to redline if you so desire.
As it comes back down to idle one of three things will happen and these are the three results:
1. Upon return to idle it hangs. Where ever it hangs in the RPM's it is running lean. Even a slight hang just before returning to idle means it is running lean at idle.(Must return directly to idle without popping,lag, or hanging).
2. Upon return to idle it goes slightly past and below idle then returns back up to idle speed momentarily. This is a rich run condition.
3. It returns directly to idle w/o any lag, hesitation, or going below idle you have a perfect a/f mixture and run condition.
Also, make sure there are no intake leaks. The rubber carb boots eventually harden and can crack. This can happen faster depending on where the bike resides (you should put your location in your profile. There might be a member nearby that can help).
Blip Test
1. Start by warming the bike up to normal operating temperature.
2. Blip the throttle up several thousand RPM's or up to redline if you so desire.
As it comes back down to idle one of three things will happen and these are the three results:
1. Upon return to idle it hangs. Where ever it hangs in the RPM's it is running lean. Even a slight hang just before returning to idle means it is running lean at idle.(Must return directly to idle without popping,lag, or hanging).
2. Upon return to idle it goes slightly past and below idle then returns back up to idle speed momentarily. This is a rich run condition.
3. It returns directly to idle w/o any lag, hesitation, or going below idle you have a perfect a/f mixture and run condition.
Also, make sure there are no intake leaks. The rubber carb boots eventually harden and can crack. This can happen faster depending on where the bike resides (you should put your location in your profile. There might be a member nearby that can help).
Last edited by CruxGNZ; 03-09-2015 at 06:25 PM. Reason: I'm a grade A moran
03-09-2015, 05:13 PM
#13
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sorry guess i misunderstood. out of the three i would say its running lean just as it passes 2k it slows and just barely pauses around 1500 before dropping all the way. also when i rev it i get a nice little puff of black smoke out the exhaust. That may be due to just idling the bike the past few weeks and the seafoam in the tank. Due to weather i haven't been able to take it out on a ride since the day i brought it home.
03-09-2015, 06:46 PM
#14
Rex Kramer-Thrill Seeker
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Sir, I'm a putz. I gave you the instructions for a "Blip Test", not the Idle drop Test, which I will give instructions for below. I appologize. However, we did find that you are running lean. Try turning your fuel screws out 1/2 turn to richen the mixture. If you want to do some reading, here is how to tune our CV carbs...click here
Idle Drop Test (taken from xlforum.net)
Not sure of the exact plugs at the moment, but it wouldn't hurt to pull them and see the condition they're in. What air filter does it have?
Idle Drop Test (taken from xlforum.net)
Bring the bike up to operating temperature. Make sure the enrichener is off. Turn the idle speed down using the idle SPEED adjustment screw (the one by the throttle cables on a CV) until the bike is only barely able to stay running, maybe a little higher than that. 800 RPM is a good RPM if you have an accurate tach. With the RPM lower than normal, you will be able to see the effect that adjusting the mixture screw has.
The idea is to turn the mixture screw in until the idle speed drops, then turn the screw back out until the idle speed drops again, and set the screw in the middle of those two points. What you are doing is making the mixture leaner, so lean that the engine does not like the mixture and runs poorly, then you make the mixture richer until it doesn't like that, and the perfect setting is half-way between the point where is falls off either way.
A couple things to remember:
1. If the bike gets overheated during this procedure, you will need to let the bike cool off a bit and try again. If you are already at operating when you start this procedure, running more than about 5 minutes while trying to get the setting correct will make the bike too hot. If the bike is too hot when you set the idle mixture, the final setting will be too lean.
2. The screw should be set at least 1/2 turn out from fully seated, and no more than 3 turns out. If it is less than 1/2 turn out from fully seated when it runs best, you should install a smaller pilot jet and perform the idle drop procedure again. If it is more than 3 turns out, you should install a larger pilot jet and perform the idle drop procedure again. If the screw ends up more than around 3-1/2 turns out from fully seated, the spring tension on the screw is insufficient and there is a chance the screw can vibrate out.
3. A tachometer is helpful for seeing the rise and fall of engine RPM if you are not comfortable listening for the changes.
4. The enrichener should be completely off to perform this procedure.
5. An intake leak will foul these results. If the mixture screw seems to have no effect, you may not be able to perceive the change in idle speed, there may be an intake leak, or you may already be either too lean or too rich and you need a different size pilot jet.
The idea is to turn the mixture screw in until the idle speed drops, then turn the screw back out until the idle speed drops again, and set the screw in the middle of those two points. What you are doing is making the mixture leaner, so lean that the engine does not like the mixture and runs poorly, then you make the mixture richer until it doesn't like that, and the perfect setting is half-way between the point where is falls off either way.
A couple things to remember:
1. If the bike gets overheated during this procedure, you will need to let the bike cool off a bit and try again. If you are already at operating when you start this procedure, running more than about 5 minutes while trying to get the setting correct will make the bike too hot. If the bike is too hot when you set the idle mixture, the final setting will be too lean.
2. The screw should be set at least 1/2 turn out from fully seated, and no more than 3 turns out. If it is less than 1/2 turn out from fully seated when it runs best, you should install a smaller pilot jet and perform the idle drop procedure again. If it is more than 3 turns out, you should install a larger pilot jet and perform the idle drop procedure again. If the screw ends up more than around 3-1/2 turns out from fully seated, the spring tension on the screw is insufficient and there is a chance the screw can vibrate out.
3. A tachometer is helpful for seeing the rise and fall of engine RPM if you are not comfortable listening for the changes.
4. The enrichener should be completely off to perform this procedure.
5. An intake leak will foul these results. If the mixture screw seems to have no effect, you may not be able to perceive the change in idle speed, there may be an intake leak, or you may already be either too lean or too rich and you need a different size pilot jet.
idle drop didn't help still just swings idle not steady at all. its a 2005 with 26000 miles on it no idea of previous service history seems to have been taken care of. What type of plugs does this thing have possibly need changed?
Last edited by CruxGNZ; 03-09-2015 at 06:56 PM.
03-11-2015, 08:53 PM
#15
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Squid
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no worries at least we found something out from it. as far as i can tell its just a stock paper type filter. thought it was a K&N when i first opened it up and it was red but it was just a paper filter.
03-13-2015, 06:03 PM
#16
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I ordered a 90 degree hex driver with the D bit today hoping this will help clear up the issue. Ive also run the tank almost dry so maybe some fresh good gas with no seafoam would be a little better for her as well. Ill check back once i get the driver and adjust the mixture screws.
03-22-2015, 07:56 PM
#18
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The Dbit to adjust the mixture screws that came with my tool didnt fit it was too big. Surprisingly thoough it seems to be idling a little better after letting a full tank with a lot of seafoam run though it and then getting some fresh gas. Im starting to ride it to work this week so ill check back after i put a few miles on her.
03-23-2015, 06:23 AM
#19
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Squid
Join Date: Dec 2014
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Check the TPS, throttle position sensor on the carb is showing 500ohms
Link here
www.vtr1000.org ? View topic - TPS
Link here
www.vtr1000.org ? View topic - TPS
04-24-2015, 06:46 PM
#20
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My Hawk just started doing this. It used to do it very rarely - it probably stalled 10 times or more on me today. Tried turning the fuel screws in for a while, then learned that this problem is usually a lean condition at idle, so will play with turning them out. They are set at 2 1/2 turns out with 45 pilot jets right now. I have tried 1.5, 2, and now 2.5 turns out with no change.
I think part of the issue may have stemmed from a bad tank of gas I got while riding in the mountains. Like a fool, I bought 89 octane instead of 87. I think nobody really uses 89, especially in the boonies, so it may tend to get "stale" where 87 (all the cheap people) and 93 (the rich beemer drivers) get used more frequently.
12,500 miles on the bike, only about 2,000 miles on the plugs.
Re-routed my vent hoses downward, will check my carb synch, check for vacuum leaks, and say three hail Mary's.
I note after reading roughly 1,000 posts about this on multiple sites (even started reading ducati sites) nobody really talks about the physics behind it.
Why does it start happening all of a sudden? In my case I guess it could have been kicked off by a bad tank of gas. Do our spark plugs foul easily, making it prone to stalling?
I love this bike - but this stuff does **** me off!
I think part of the issue may have stemmed from a bad tank of gas I got while riding in the mountains. Like a fool, I bought 89 octane instead of 87. I think nobody really uses 89, especially in the boonies, so it may tend to get "stale" where 87 (all the cheap people) and 93 (the rich beemer drivers) get used more frequently.
12,500 miles on the bike, only about 2,000 miles on the plugs.
Re-routed my vent hoses downward, will check my carb synch, check for vacuum leaks, and say three hail Mary's.
I note after reading roughly 1,000 posts about this on multiple sites (even started reading ducati sites) nobody really talks about the physics behind it.
Why does it start happening all of a sudden? In my case I guess it could have been kicked off by a bad tank of gas. Do our spark plugs foul easily, making it prone to stalling?
I love this bike - but this stuff does **** me off!
04-26-2015, 04:04 AM
#21
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SuperBike
Join Date: Mar 2012
Location: New South Wales Australia
Posts: 1,544
Jeez,
Those octane ratings are low!
I run mine on 95 that has no ethanol.
We also have 91 with ethanol, 91 without and 98 without Ethanol.
I find my bikes runs the best with the 95 in it.
Different countries, different elevations , different fuels makes carb tuning different in every location.
My bike is a 2005 and I was having all sorts of problems with idle etc and must of had the carbs off fiddling with them about 10 times. I noticed that the clamps on the inlet rubbers were a bit the worse for wear and decided to replace them.
At the same time I decided to replace the inlet rubbers while I was in there and fit some remote vac lines.
Did all that and then synced the carbs and did the mixture.
Guess what! Totally different bike and the worst part is that I will never know what caused the problem in the first place as I replaced several parts at the same time.
This is not the first time this has happened to me with this bike. I believe that it is caused by the fact that it has carbs and that they can't talk to you like a fuel injected bike can via the ECU and they make you work out how to rectify the problem without being able to refer to a code in a manual that has all the answers.
I like the VTR for the fact that it involves you in keeping it maintained and it's a fun ride when it is going good. There's nothing like the pissed of look on a mate who has a crotch rocket and you just smoked him. Priceless!
Check your inlet rubbers and clamps, you never know and if it's not that cross it off the list.
Good luck.
Those octane ratings are low!
I run mine on 95 that has no ethanol.
We also have 91 with ethanol, 91 without and 98 without Ethanol.
I find my bikes runs the best with the 95 in it.
Different countries, different elevations , different fuels makes carb tuning different in every location.
My bike is a 2005 and I was having all sorts of problems with idle etc and must of had the carbs off fiddling with them about 10 times. I noticed that the clamps on the inlet rubbers were a bit the worse for wear and decided to replace them.
At the same time I decided to replace the inlet rubbers while I was in there and fit some remote vac lines.
Did all that and then synced the carbs and did the mixture.
Guess what! Totally different bike and the worst part is that I will never know what caused the problem in the first place as I replaced several parts at the same time.
This is not the first time this has happened to me with this bike. I believe that it is caused by the fact that it has carbs and that they can't talk to you like a fuel injected bike can via the ECU and they make you work out how to rectify the problem without being able to refer to a code in a manual that has all the answers.
I like the VTR for the fact that it involves you in keeping it maintained and it's a fun ride when it is going good. There's nothing like the pissed of look on a mate who has a crotch rocket and you just smoked him. Priceless!
Check your inlet rubbers and clamps, you never know and if it's not that cross it off the list.
Good luck.
04-26-2015, 09:14 AM
#22
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04-27-2015, 06:07 AM
#23
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Well, even thought I had synched them about 6 weeks ago, I synched the carbs again yesterday, AND - they were slightly out of whack. I did put another 1 1/2 gallons of fresh fuel in the bike too, so perhaps it was a combination of fresh fuel (all the crappy 89 octane mountain gas being gone) and better synch of the carbs.
It still confuses me as to why they get out of synch - it's a mechanical linkage between them - what changes?
BUT - I rode yesterday afternoon, smoother idle, no clunk and die, and idling at about 1100 rpm. Note that it was much cooler outside, and my bike seems to run noticeable better in cool temperatures.
This coming winter I think I will replace the rubber intake boots, probably replace the fuel and vacuum lines, replace the float needles, and maybe even spark plugs and check (or trim?) my spark plug wires. All that stuff is 18 years old by now - pretty old for rubber parts exposed to high heat and gasoline.
It still confuses me as to why they get out of synch - it's a mechanical linkage between them - what changes?
BUT - I rode yesterday afternoon, smoother idle, no clunk and die, and idling at about 1100 rpm. Note that it was much cooler outside, and my bike seems to run noticeable better in cool temperatures.
This coming winter I think I will replace the rubber intake boots, probably replace the fuel and vacuum lines, replace the float needles, and maybe even spark plugs and check (or trim?) my spark plug wires. All that stuff is 18 years old by now - pretty old for rubber parts exposed to high heat and gasoline.
06-11-2015, 04:48 PM
#24
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Squid
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im still having the problem actually seems like its getting worse. Any way it could be spark plug related? I have no idea when the last time they have changed was its got about 26k on it. I still need to set the tps as well but it just seems to be getting worse.
06-12-2015, 05:33 AM
#25
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I found out my enrichener (choke) fittings where the choke cables enter the carbs were jerry rigged by the previous owner. I replaced them with some brass ones from Mark on the VTR1000 site, cleaned the enrichener valves, synched the carbs, and the idle is smooth as silk.
Did a commute to work the other day in heavy traffic, long waits at traffic lights, nice steady, smooth idle at 1200 rpm.
Did a commute to work the other day in heavy traffic, long waits at traffic lights, nice steady, smooth idle at 1200 rpm.
06-12-2015, 07:10 PM
#26
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Squid
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so i did some testing tonight at the battery at idle i was 14v but when i popped the throttle it dropped to as low as 12.xx volts. is it possible my regulator is out? I just ordered a jet kit and will clean the carbs before i put it in but im wondering if voltage drop like that is normal? I figured higher rpm would mean higher voltage. possible bad battery?
Last edited by FbodyLT1; 06-12-2015 at 07:12 PM.
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