Checked my valve clearances today after having the bike for over a year now (better late than never I suppose), and having seen a lot of talk before about running the exhaust valves more open than spec, I was hoping for a bit of input on my situation.

Left exhaust:
Biggest feeler = 0.04mm
Current shim = 2.72mm
Proposed shim = 2.70mm
Proposed clearance = 0.06mm

Right exhaust:
Biggest feeler = 0.06mm
Leave as is

Left intake:
Biggest feeler = 0.03mm
Current shim = 2.6mm
Proposed shim = 2.55mm
Proposed clearance = 0.08mm

Right intake:
Biggest feeler = 0.06mm
Leave as is


It's an '06 with ~24k miles on it. I was planning on keeping to spec as opening the exhausts to 0.11mm clearance seems very high, but any comments would be appreciated.

go with your plan!   Perfect!

Only one thing...check your clearances again AFTER you put in the new shims...turn the engine over a bunch of times to seat everything.

Even though your math "adds up" perfectly..sometimes it just doesn't measure up to what the math says it should be.



Some go really loose, especially on the exhaust...I don't like this...stay in spec and it's all ok


Maybe if the exhaust was measuring .04...I'd go one wider to .09....but no need to run .10, .11, .12, .13  like some do.

Cookie

Thanks, I've gone for the sizes I suggested yesterday so I should be back on the road in no time!

I'll definitely double check the clearances after to log them for next time, but as one of the valve cover bolts was almost rusted in place it's obviously been a while since they were done, so hopefully won't need doing again any time soon.

Keep that 272.  Those sizes are not available, except when they come in the bike from the factory.

Got them changed over and final clearances are 0.06mm on the left exhaust as calculated, but 0.06mm on the left intake compared to the predicted 0.08mm. Although it makes them all the same which pleases my OCD haha.

At £10 a shim I'm definitely not getting rid of the old ones! It's probably not necessary but I've coated them in oil and will keep them in a ziplock bag to prevent any oxidation.