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Discussion Starter · #1 ·
Hi all. Hope someone can help me.
I have a vibration through the bike while under load. It idles smooth as and once you are cruising the vibration stops. But as soon as you accelerate the vibration returns. I did have the exhaust fall off the back pot. Does use a bit more fuel than normal. Vibration is through the whole bike. All engine bolts tight.
‘I have replaced the crank sensor. Fault code.comes up is the PO151.
 

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How many miles are on the bike?
Try to determine if the source is in the engine or in the frame:
Any wobble in the bike when hitting small changes in the road (bumps / dips rain groves)?
Have you performed a fall away check? (Neck bearings)
How long since the wheel bearings were changed?
When stopped does this vibration increase with RPM or stay the same?
Does it happen when engine braking?
Any noise associated with it?
Take a look at the drive belt tension and condition of the belt and sprockets.
Does the rear sprocket have excessive movement?
 

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Discussion Starter · #4 ·
How many miles are on the bike?
Try to determine if the source is in the engine or in the frame:
Any wobble in the bike when hitting small changes in the road (bumps / dips rain groves)?
Have you performed a fall away check? (Neck bearings)
How long since the wheel bearings were changed?
When stopped does this vibration increase with RPM or stay the same?
Does it happen when engine braking?
Any noise associated with it?
Take a look at the drive belt tension and condition of the belt and sprockets.
Does the rear sprocket have excessive movement?
155000. Bearing replace. 40 k ago No vibration when stopped or idling. Constant under load. Not when breaking no noice. New belt and sprockets No noise. No excessive movement
 

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155000. Bearing replace. 40 k ago No vibration when stopped or idling. Constant under load. Not when breaking no noice. New belt and sprockets No noise. No excessive movement
Have you checked the motor mounts for torque and inspected for torn rubber, as Candyman posted?
 

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Mr. James
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Have you addressed the O2 issue yet? That is what that code is telling you. Low voltage signal. That means both cylinders are not pulling the same and that is likely what your vibration is. You may want to get that taken care of before some real damage comes about.
 

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Discussion Starter · #7 ·
Have you addressed the O2 issue yet? That is what that code is telling you. Low voltage signal. That means both cylinders are not pulling the same and that is likely what your vibration is. You may want to get that taken care of before some real damage comes about.
Thanks mate no one has told me that.
 

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Discussion Starter · #9 ·
Have you addressed the O2 issue yet? That is what that code is telling you. Low voltage signal. That means both cylinders are not pulling the same and that is likely what your vibration is. You may want to get that taken care of before some real damage comes about.
what do I replace. Is that the compensator that could be faulty
 

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Is that "PO151" Code current? If so, it's telling you that the rear cylinder is running lean. This could be from a dirty injector or more likely an exhaust leak (especially since the muffler fell off).
That will make the bike run like crap and can cause detonation in that cylinder (That's BAD)! Check the spark plugs:
If the there are hard bumpy deposits on the spark plug, that is the indication of detonation. (The air fuel mixture in that cylinder is literally eating the piston) Fix the exhaust leak!
If the code is historic, (from when the exhaust fell off) and there is no leaks in the exhaust. You can clear the code. IF you clear it and it comes back, then it is a current code.
Here is a link to really understanding how to read a spark plug:
 

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Discussion Starter · #13 ·
Thanks mate I have noticed there is a sensor on that rear pipe just down from the. The dealer told me that the air sensor is not connected as it’s not needed with the race tuner it has.
 

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Thanks mate I have noticed there is a sensor on that rear pipe just down from the. The dealer told me that the air sensor is not connected as it’s not needed with the race tuner it has.
That will certainly throw the engine code! Watch that video then check the plugs anyways. Because if there is a exhaust leak it will still cause the lean condition in the cylinder. The spark plugs indicate the cylinders health! computerised or not! Back in the day they were the only way to troubleshoot with any accuracy.
 

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Discussion Starter · #15 ·
That will certainly throw the engine code! Watch that video then check the plugs anyways. Because if there is a exhaust leak it will still cause the lean condition in the cylinder. The spark plugs indicate the cylinders health! computerised or not! Back in the day they were the only way to troubleshoot with any accuracy.
Thanks will check em out
 

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Both plugs are showing a bit of a rich air fuel ratio! Zero signs of dentanation. The rear plug has more carbon deposits than the front one. Yet the bike is throwing a lean code?
WTF? I only wish i could get my plugs to run close to that rich.

They look like they are running on the cold side (The rear plugs insulator is dark). Increasing the heat range should help with that, unless it's been idling before those plugs were pulled.
I'm not seeing anything that would cause a felt performance issue either way. Certainly not a power vibration...

What the heck else would cause vibration only when accelerating? Are there any noises associated with the vibration? (Kinda hard to hear over the pipes)
Does she make any clunking or hammering noises when starting or stopping the engine?
 

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Discussion Starter · #20 ·
I am replacing the compensator and starter clutch as the SC was on its way out. 2nd one in 150000 k. Will see how that goes.
 
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