Can't remove valve shims on intake side, too tight to measure clearance

zimzim

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Hey all, new to the forum, just picked up an 82 cb750c last spring and tuning it up for use this summer. I'm checking the valve clearances per the service manual, and exhaust is all nicely between .003" and .005", but intake are all tighter than .0015" (smallest feeler), and I can't use the valve depression tool (this one https://fortnine.ca/en/motion-pro-v...eTxEH4QECNaEy78epnImh1zrXDr9AUhYaAkzNEALw_wcB), to even remove the shims. Anyone have any idea if the problem is user error or the previous owner slammed monster shims on and now I'm hooped?

Thanks
 

pidjones

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Are you pushing the tool handle all the way down with tha cam lobe pointing away? Sometimes they will stivk a bit due to the oil forming a seal. I use a small screwdriver to worry them loose and sometimes a magnet to pull them out. Unless the keepers are missing, that should do it.
 

zimzim

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Not a problem with the shims, there was not enough actual clearance to get the tool in. I've managed to get the tool in partways, depress the buckets a bit, stick a screwdriver in the gap, and remove and reinsert the tool to remove the shims now.
 

pidjones

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The tool goes between two buckets - there should be no problem getting it started. It doesn't mater what your valve clearance is as it doesn't go against a cam lobe, but rather between two lobes. Do be careful to not snap the cast tool off, however - press toward the cam as you press it down - it should catch two buckets with a small projection keeping the tool centered between them. Once pressed down all the way, you should be able to remove either shim (but please, only do one at a time to avoid mix-up). The tool will stay in place while you measure/exchange shims. Before inserting the tool, use your small screwdriver to move the bucket notches away from the tool area so that as the tool goes in it will rotate both buckets into a point where the notch will make it easier to remove the shim. #2 exhaust may be easier to take out the front. A magnetic pick-up tool, pair of tweezers, and small screwdriver can help.
 

zimzim

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The thing is there is a problem getting the tool in, but on the intake side only. I have no issue on the intake, but it seems like it's time to do what I can this time and then run the bike into the ground.
 

pidjones

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I really can't think of a reason for the intakes to be harder than the exhausts. You just do it toward the back instead of the front. The exhausts do run hotter and are more prone to burning if the clearance is too small as the valves beat the seats down and eventually can't transfer heat to the head. Intakes can, but exhausts run much hotter anyway.
 

user8086

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Just make sure your tool is fully depressed... With The notches of the buckets pointed towards you... And just pop them out with a small pic retrieve them with a small magnet sometimes the oil does create a bit of suction.
 
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