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Old 12-13-2012, 11:43 PM   #24
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Joined: Sep 2004
Location: Main Street, Shedd, Oregon
Oddometer: 2,099
Yeah, do some extra work to get them all on the loose end of the range. It'll run better. 30k is a good time to do this because they don't change much from here on out.

Honing them with sandpaper is only good for 0.001" (0.025 mm). You must start with 100 grit, then 200, 320, 500 and you may get only a small change.

For temp changes aluminum head will change more than the steel valve stem. At cold temps the clearance will be smaller, the alum shrinks more and pulls the cams closer to the valve seat. But, when the bike is running, the parts don't have the same temp. The alum head will only get to 200 deg F, but the valves may go to 300 F for the intake and sometimes 1200 F for the exhaust. This will close the clearances, much more for the exhaust. That's why it has more clearance to start with.

Humm, Kali. Doesn't suck much right now.
"Dad, can I get a motorcycle when I grow up?"
"Son, you can't do both"
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