Topic: adjusting valves...proper setting?

[oldk6guy]

i have the original owners manual for the bike and it says to set the valves to int. 0.05mm or 0.0019in and exh at 0.08mm or 0.0031in. there is no way that is correct. i dont believe that a feeler gauge has ever been made that thin....any help would be greatly appreciated.

[oldk6guy]

bike is 76 cb750k6

[74750k4]

Factory recommended values:


INT .003" or, .0762 mm

EXH .004" or, 0.10 mm

Many run .005" all around.

[greenjeans]

They make em....   impossibly thin and easy to crease, but they make them.    Try Napa.

[RebelYankee]

I got a set of feeler gauges from my Dad and they go thinner than .002. 

http://www.amazon.com/Lisle-68100-Deluxe-Feeler-Gauge/dp/B0009OMY9C/ref=sr_1_2?ie=UTF8&qid=1373908951&sr=8-2&keywords=feeler+gauge

[oldk6guy]

are there benefits from going .005?

[iron_worker]

More gap will result in:

-Less total lift
-Less open duration
-More time on the seat (allows heat rejection from valve to head... less burnt valves)
-More valve noise

IW

[Dave Voss]

are there benefits from going .005?

I adjust the valves to .003" INT and .004" EXH, which is 1 thousandth more than the factory setting.  Besides the benefits listed above, it also provides a bit of extra protection against loosing compression if the engine overheats enough to close up the smaller stock valve clearances.  Granted, that is an unusual circumstance, but it can happen under high load in really hot weather if the carbs are running lean for any reason.  At the slightly larger valve clearances, the valve train noise is just slightly more when the engine is cold, but about the same as stock once it is warmed up.

[tomkimberly]

+1, always set them large on these old bikes.

Tom