2 replies to this topic

Posted February 16, 2005 - 09:25 PM


Well i got the auto decomp cam today, i put it in i started to shim it. This is my question, when shiming the valves how much resistence should there be when i slide the feeler gauge in?. The reason i ask is because when i put in a .25mm feeler gauge there is some resistence in it, i cant move it up and down at all while its in between the shim and cam lobe and it feels like theres enough resistence to not have to get shims and it still feels good when i put a .20mm gauge in too. After reading all the posts and 95% had to get new shims im wondering if i should just buy the next size up(195). My dad checked them and he said they should be fine. BTW both valves feel the same way and left side has 189, right side has a 188.

Any opinions are appreciated

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  • yzfxr

Posted February 16, 2005 - 11:20 PM


there should be a "light drag" on the feeler, but that can be interpreted differently.
use the largest feeler you can get in there comfortably, you shouldn't have to force it in though. so if a .25 fits snug, but a .30 won't fit, then the clearance is .25. it won't always be an exact clearance, thats what the tolerances are for.

  • grayracer513

Posted February 16, 2005 - 11:44 PM


Try a .26 gauge. That should be a "no go". If you don't have one, remember that the .20-.25mm spec is roughly equal to .008-.010", so you could use an .011" gauge to check this.

The feel is an acquired thing. The gauge should glide smoothly without sticking for catching as you pull it on the minimum reading, but not so freely on the max that it won't stay in place when you let go of it.

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