Valves, shim 'em or send it?

[N4teTheGreat]

Checking valves in my KTM, need to find out from Lucy what they were at after she set them last, but they're ok ish. Exhaust valves should be from .25 - .3, the .3 shim doesn't wanna go, the .25 slides in with negligible resistance, so it's somewhere between the two I think.

Intake is on the loose side of spec at .15 across the board with one of the intake valves on the front cylinder feeling slightly tighter, so maybe .12?

I ride this bike in a spirited manner but I'm rarely wringing it's next or getting anywhere near redline. I'm debating between adding shims to the exhaust to put them a bit loose (only .05 increments available from KTM apparently) or just putting the thing back together an expecting to do actually make adjustments at the next 9k service.

What would moto jesus do?

 

[ST Guy]

If they are in spec, I’d button it up and ride.

 

[ichabodnt650]

If I have to pull the cams off, I'd defer until next time (when they're too tight out of spec.)

If I feel like the valve intervals are long enough (20k miles between inspections) I might bite the bullet and set them all to the looser end now while I have the body panels, tank, smog plumbing, off.

By the way, Japanese bikes spec. looser requirements, typically ±2 mils (±.05 mm) from center. KTM spec. theirs tighter ±1 mil (±.025 mm) from center. The metallurgy doesn't care if you're Austrian or Japanese. Perhaps ready-to-race demands that extra precision so KTM spec. theirs tight like that. It's silly.

Yours are fine, at center or slightly toward the loose end. Valve seat wear seems to migrate clearances tighter over time (from a dozen or so I've done). Lucy had them in the right place.

 

[auntiebling]

loose valves are happy valves
loose lips sink ships

relevant?
not really

 

[OaklandF4i]

I always adjust mine on the loose end of things, happy as auntiebling said. If you are the type of guy who checks valves often as directed, note the measurements and ride. If you aren't, and rarely check them.... adjust them now.

Edit: if and or when they start moving regularly, I begin to check more often with the understanding I need to start saving for a valve job. In my experience, valve wear has less to do with how we ride than the envirement we ride in, and where they are on the hockey stick graph of wear (ie they move real fast at end of life.)

 

[Lucytriple]

Checking valves in my KTM, need to find out from Lucy what they were at after she set them last, but they're ok ish. Exhaust valves should be from .25 - .3, the .3 shim doesn't wanna go, the .25 slides in with negligible resistance, so it's somewhere between the two I think.

Intake is on the loose side of spec at .15 across the board with one of the intake valves on the front cylinder feeling slightly tighter, so maybe .12?

I ride this bike in a spirited manner but I'm rarely wringing it's next or getting anywhere near redline. I'm debating between adding shims to the exhaust to put them a bit loose (only .05 increments available from KTM apparently) or just putting the thing back together an expecting to do actually make adjustments at the next 9k service.

What would moto jesus do?

Yep, I think your little heart will be happier if you get a new set of feelers gauges that has a 28!