Compression question

[cb750k603]

I have a 82 CB750K, approx 26k on the clock.

I was having an issue with bike stalling at idle when warm. I had the carbs completely serviced and valve clearance checked. 4 of the valves were tight. I've replaced the shims and clearance is now in spec. Compression in all 4 cylinders is about 100 psi +/- 3.  My Clymer indicates compression s/b around 170 psi +/- 14.  It also states that I should be more concerned with variances between cylinders. Since all 4 cylinders are with 3psi, am I ok?  It would seem to me that if spec is 170 and I'm down to 100, I have a issue.  Any comments or suggestions would be most appreciated.

Thanks

[shadow06]

if the throttle was not held wide open while cranking the engine ,this would explain the lower than normal compression reading .as the throttle valve plates would restict the air flow

[cb750k603]

shadow06 wrote

if the throttle was not held wide open while cranking the engine ,this would explain the lower than normal compression reading .as the throttle valve plates would restict the air flow

Thanks Shadow. I rechecked compression this morning (throttle held wide open) and now I have all four cylinders @ 120 psi, all within 3psi.  What are your thoughts with 120psi?  Am I ok or do I have an issue which needs to be corrected?  Again, thank you!

[shadow06]

you have a 82 bike with only 26k .it has been sitting a long time .it needs a long ride ,like 1000 k then reset timing chain and check valve clearance  clean and gap plugs and recheck compression .if idle stall when warm is the only problem ,bring your idle speed up a bit and leave it there for the next 1000k .with out knowing the history of the bike .i would try that before chasing ghosts and give the bike a chance to loosen up a bit and the clean fuel you put through it will help to wash out some residue and perhaps solve the idle  problem ,if not remove and clean the low speed idle jets .compression is not the problem it is very good .

[shadow06]

one item i forgot to ask that could effect both compression and idle problem is how clean is the air filter ?? can,t believe i over looked that