[Jx_hennessy]

This is a 2008 Yamaha R6. I took my bike to get some work done it by a local mechanic, I had the bike back for a few days, the next day I went to start the bike up, it was hard to start and when coming up to a stop it would shut off and be very hard to start, even when hot (I suspected valves were right immediately).. I pulled the top end off and to my suprise this is what I found. On the images, I even have issue getting the valve bucket removed.. Do I need a new cylinder? Or can this be repaired?? I also bought a 2007 Yamaha R6 last week and was wondering if the cylinder heads are same for years 2007 and 2008, I was wondering if I could just swap out the cylinder head and buy a new gasket.. Will this work or not?

 

[Intuit]

Wow... never seen that before. Looks like it was starved of oil somehow. Ordinarily there's a healthy amount of lubrication up there. Shredded clutches have been known to clog the oil cooler on the front of the engine. Other than that, has to be low/no oil, severly overheated and/or severely neglected oil. Check the rest of the motor for evidence of overheat/starvation as well.

3rd-Gen parts should be the same. Should work; but seek a second opinion to be sure.

 

[Jx_hennessy]

e

Wow... never seen that before. Looks like it was starved of oil somehow. Ordinarily there's a healthy amount of lubrication up there. Shredded clutches have been known to clog the oil cooler on the front of the engine. Other than that, has to be low/no oil, severly overheated and/or severely neglected oil. Check the rest of the motor for evidence of overheat/starvation as well.

3rd-Gen parts should be the same. Should work; but seek a second opinion to be sure.

No other signs of oil starvation, so am suprised as well. The only thing I could say is that the cam bolts caps, two of the threading were gone, so am not sure if that would be the cause

 

[Intuit]

Cam bolt bores barely hold to torque spec, particularly when there have been multiple valve-checks on an engine. People have been known to strip the bores.

Theory? - Cam bolts backed off enough to allow the gap and head to separate a little. Oil was then sheared-off in that gap, leading to starvation?

 

[Outside World]

Holy, that´s pretty impressive..

If multiple valve-cheks were done, or the engine was just open alot, could changing the bolts "prevent" a thing, like this? or would it just be w.e?

 

[Intuit]

As far as my experiences go, unfortunately it's not the bolts that begin to strip, but the bores in the head.
Next time I go into it, will have to reduce torque a little and use red thread-locker adhesive.

 

[Jx_hennessy]

Am currently in search of a used cylinder head in working condition, if anyone knows where I can get one. I can't find any on ebay that fir 08+