Stupid me- did the test wrong

[Jethro]

Yesterday while I had the tank off the bike for a carb synch, I decided that the engine was hot, why not do a compression test? So I went through the whole thing getting only 120 per cylinder. Even, but not great. About an hour later, tank back on, bike ready to roll I remembered- I didn't hold the throttle open!

Does my test tell me anything or do I have to do it again? I know my mistake will result in an inaccurate test, but does the even psi per cyl tell me anything?

Stupid. I shouldn't be allowed to have tools.

[lhanscom]

Well the even numbers tell you that the cylinders will probably have even amounts of wear, but it doesn't tell you what level that wear is at. If you want to know, do i t again, if you're not having any issues, just ride. You have a list of things to do anyway right? So why not wait until after you do the valve adjustment to check the compression?

[Anonymous]

If you're working on a pro stock drag bike or a pro roadracer, it may be worth re-testing, but for an average bike, and the results you have, it's sure not worth the trouble.

[Anonymous]

120 PSI in each cylinder (nice and even) and with the intake butterflies closed is quite a good reading

I would not be surprised that you would get 160+ in each cylinder.

If you must test, check one cylinder only (with all the plugs removed and the throttle wide open)

This one cylinder reading should be indicative of all 4 - since your first test proved they were similar.