Uneven exhaust beat

[rochep]

 Hi , I have a 350Ypvs F2.The strenght of the exhaust fumes flow from the left hand exhaust pipe is much stronger than from the right hand exhaust pipe.

Is this normal, or is it simply a blockage in that pipe ?

rochep

[Dave B]

It's not normal.
It might be a blockage in the pipe, or a problem in the right hand cylinder, or a leaking gasket, or an ignition problem, or the right carb could have a blocked jet, or an air leak, or......
You need to do some tests. You've found the symptom, now you need to do the diagnosis, then the cure.
Try the good old standard tests.
Compression Test, a leakdown test, Swap the plug leads, clean the carbs. If you still have standard pipes with removable baffles, take out and clean the baffles.
By that time you will know whether you need to lift the heads to check for a broken ring etc.
Cheers
Dave

[Rob123]

I had this on my lc the left hand was alot stronger cleaner running than the right.
After nearly every test possible it boiled down to the hole in right hand carb pilot jet was alot bigger than it should of been like someone had drilled it out.
I swapped carbs around and tried it that told me it was an issue with the carb as the other side ran crap then.
It might be a case of unbalanced carbs aswell as all above as dave has said.
Good look 😉

[rochep]

Many Thanks Dave .
It was in a Bike shop a few weeks ago.
I was told that the YPVS cable was connected the wrong way round, and that a stator bolt was rubbing off the flywheel, making a noise.
All fixed.It now responds instantly to a throttle blip.But the old problem of the uneven exhaust beat remains.
So I can rule out compression problems.
Re the carbs - they are power carbs, bought second hand.Funny thing, the fuel tranfer pipe opens into the right hand carb, but its opposite
on the left hand carb is blind ie blocked. Could this be my problem ?
Paul Roche

[rigga]

Could be reeds too


Just to add another variable