definatly check out the compression, could be rings, or stuck valve or somthing

 

Well, yeah, I knew that. I asked the question weird. I HAVE a compression tester (somewhere. . . . ) but I've only known it to be for use on cars. It says it's "universal," so does that include bikes? Don't have the service manual here at work, so do you know what PSI I'm looking for it to be?

 

Universal ones just have multiple adapters with different sized threads so that you can thread it properly into where your spark plug goes. 179-183 is for the F2. I think you don't want to be more than 10psi off. Don't quote me on that though.

 

U want more than a 10% difference between cylinders, Also before you do the compression test start up your bike turn the fuel to "off" let it run until the bowls are empty, then take out the fuse for spark and do your compression check, this prevents fuel from just sitting on your pistons/cleaning the walls while you are doing the compression check. This is a dry check, you should also follow this check with a wet check if the overall compression is low- I.E. add a little Marvel's Miracle oil to each cylinder (or any oil at all I just have always used Marvel's for wet tests); and repeat the compression test. If the compression jumps up then the rings are bad-plainly put. If there is no difference, but the reading is still low, pump air into each cylinder, if you hear it out the exhaust- exhaust valves are toast: out the intake side- well u get the idea. Engines are simple really- all you have to do to evaluate them is step back look at the function of each stroke and simulate it to figure out what is bad.

 

Perfect response. I hope it doesn't come to that, though. Thanks guys!

 

You have to make sure your valves are closed by rotating the crank before getting all worried when you hear pumped air getting passed your valves.

And unless something broke, I doubt it is a valve problem. I have 55k on my bike, beat the **** out of it, and still haven't had to adjust clearance yet. F2's and F3's are tanks