VTR vibration woes, any ideas ?

[sirch345]

One thing that bugs me relates to a query I put into this forum earleir this year.
When I went to fit the chain and sprockets, there was lateral play on the drive shaft sprocket, i.e even with a new bolt and washer torqued up properly you could still feel play in the sprocket along the direction of the shaft, not on the splines itself.
One chappies reckoned this was normal, but if any of you get the chance, I'd be interested to see if its the same on your VTR. (You can get your hand in behind the clutch mechanism cover quite easily)

To put your mind at rest regarding the front drive sprocket.

I've had my bikes rear end stripped down this week for servicing etc so I purposely checked the front sprocket for you.

Mine has the original sprocket fitted from new (20,000mls done now) and it does have play along the direction of the shaft, also on the splines itself. Probably a new sprocket would have less play on the splines itself more like yours.

So from that IMHO I'd definitely say yours is normal

Chris.

[MarkHunt]

Hi Mate,

Sorry haven't answered sooner, but been pre-occupied work-wise.
Firstly many thanks for putting my mind at rest regarding the sprocket.

I tracked down some of the vibration to an incorrectly fitted exhaust system that was resonating through the mounting / footrest hanger. The dealer found the valve clearances and carbs were normal, so I'm still in a bit of a dilemna what to do next re-low compression. To cap it all, the day after I picked up the bike from the dealer, I took it for a blat just to see how it was going, during which I missed two gears in close succession, happened to glance down to see my left boot coated in oil because the timing cover inspection cover had not been tightened properly and had dropped off. Just got a new one from David Silver, so I'll carry on my process of elimination, but I'm still worried that the compression is low and it feels a bit below par engine-wise.

Mark

[sirch345]

Hi Mark,

It's good too hear some things have been ruled out but still a bit odd about the low compression.

Have you checked to see if the crankcase is becoming pressurized by removing the oil filler cap and placing you hand over the outlet before you start the bike, then keeping it there start it DO NOT STICK YOUR FINGER IN THE FILLER CAP HOLE WHEN THE BIKE IS RUNNING If there's excessive pressure there it could be a broken piston ring or similar

I personally think though it's more likely the valves are not sealing properly, that is of course if I've read your reply correctly and that the valves and valve seats have not been checked.

Chris.

[MarkHunt]

Thanks again for the advice.

Fitted timing inspection cover today and checked the other one in the cover only to find that it was loose as well, so definitely never going back to that dealer again, no matter how convincing he was...

Checked TPS and noticed that the retaining plastic bracket was broken, so took it off, checked it and re-fitted. Bike is definitely running better, still a little vibey, but I'm going to re-fit the exhaust system at the weekend.
Performance-wise, it still shifts, just lacks a little torque from what I remember, so I don't feel that the problem is terminal now, despite the compression prognosis.

Much happier now, maybe it's just a combination of the TPS and getting a little old...

regards

Mark

[tony.mon]

I've noticed that there's noticeable vibration through the pegs when running the standard heavy exhausts for the annual MOT.

As soon as I get the Carbon straight-through's back on it disappears.