Top end replacement

[yz fan]

I have a '87 yz 250 I bought 6 months ago, it runs as good as when I got it. It now has about 50 hours of time on that top end, would it be a good idea to change it out now? Would there be any signs that I could see or hear that would tell me it was going bad?
I've been using super M at 32:1 above 5000ft sea level. Thanks guys!

 

[Danman]

You can use a compression guauge and check every so often and write it down. That way you will know when you start to loose compression. If you check it the first time and its out of spec you can replace it then.