Compression test

giving the fact that the compression is lower w/ a cold engine id say you are fine, but im no expert.

I've done it with a cold engine and then warmed the engine and did it again and noticed only about 5 psi change. I usually do it on a cold engine because it is more convenient. I take a reading after break-in for a reference point, and then every 10 hours or so just to make sure rings are still sealing well.

a compresion test is excellent for telling how well the rings are sealing but if you have a lot of time on a cast piston could be cause for alarm. your statement of being a year concerns me.

a friend of mine had an 88 rm 250 with a stock piston in it that ran decent up until the piston shattered. With a slightly worn bore and a cast piston the skirts of the piston couldnt handle the rocking motion and a made a big mess.Yet the rings were still sealing enough to have decent feel of compresion at the kickstarter,start easily and run well. Some bikes are more problematic than others , how big the ports are and the piston contact area has a lot to do with this type of failure I am sure. Just something to think about besides just relying on a compresion test numbers.