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Old 07-28-2021, 04:40 PM   #16
auburn
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Hah yeah that definitely sounds like Fog. Copy though, that makes sense.
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Old 07-29-2021, 11:34 AM   #17
dmfdmf
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Originally Posted by afm199 View Post
When does too tight make a difference? Basically not until the valve never closes all the way.
True for intakes but for exhaust valves the seat dwell time is crucial for valve cooling. Exhaust valves will burn if dwell time is too short.

On my 'Strom (street bike) I put the intakes at mid-spec and exhausts at wide spec to maximize time between adjustments (exhausts wear faster). Racers run both at the low end of the spec for max performance but check them regularly.

Also, check out RockyMountain ATV for 0.025mm increment shims, at least for the Suzuki motors. They sell individual shims so you can get the gaps spot on and they have fast turnaround.
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Old 07-29-2021, 04:08 PM   #18
bpw
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Originally Posted by dmfdmf View Post
True for intakes but for exhaust valves the seat dwell time is crucial for valve cooling. Exhaust valves will burn if dwell time is too short.
Is dwell time really going to be effected in a meaningful way until the valve isn't closing though? The cam closes the valve for ~180+ degrees of the rotation as long as there is more than zero clearance, a couple degrees one way or another isn't changing much.

Last edited by bpw; 07-29-2021 at 04:10 PM..
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Old 07-29-2021, 04:33 PM   #19
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Originally Posted by bpw View Post
Is dwell time really going to be effected in a meaningful way until the valve isn't closing though? The cam closes the valve for ~180+ degrees of the rotation as long as there is more than zero clearance, a couple degrees one way or another isn't changing much.
I agree. As long as the valve is closing completely, you wonít have a problem.
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