Compression Test Query

[arbadacarba]

So I've had my bike for a couple of years now, and as it's my first bike, I have nothing to compare it too.

Also, I'm a tinkerer, I'll take on projects to learn how things are done as much as to really try to accomplish any improvements.

So, after checking the valve clearances on my '95, and adjusting them into spec (they were all slightly out of spec) I thought I'd do a compression test.

The results were a little disturbing:

1-130
2-90
3-120
4-120

The bike has been sitting all winter with a bit of oil in the cylinders, if that makes any difference.

My SOtP-o-Meter tells me the bike was running really well before I put it into storage.

Has anyone else had any experience along these lines?

[TLRam1]

Not sure what the reading should be on these, but on the number 2 cylinder you may have the valves too tight, 90 is too low.

I would guess you are on the low side of the compression scale.....that's just a guess, on my two stroke once I hit around 110 PSI or lower I am looking at a top end.

Valves on these really do not need adjustments from the experience of the board members.

Did you recheck the clearances once you replaced the shims?

[arbadacarba]

Some kind soul reminded me to open the throttle WIDE when doing the test... Oops, forgot to open it at all... I'll re run the test and report back.

As for the valve clearences, mine were clearly out. I actually only had to replace a few shims as many of them just moved to other positions and the largest ones were replaced.