85 200s problems

[nova_gh]

Just finished up doing an little overhaul of my Honda 85 200s, replaced a lot of stuff but didn't get into the motor. Mainly cause i couldn't get the allen bolts on the head to bust loose. The engine idles really well, but when i get up to speed and at higher RPM's it starts missing and sputtering. If in 5th gear, keep it about 1/4 throttle and it runs great, any more and its acts up. Went though the carb, should be pretty clean.

Inside the motor has never been touched, this is a family machine and i know its history. I've got a feeling its probably piston rings, but i wanted to see what the experts have to say, any ideas?

[UI Vandal]

Possibly running lean at WOT? Have you adjusted the pilot screw appropriately? As for rings, have you checked compression? Does it smoke even after warming up?

[nova_gh]

i keep forgetting to check the compression for some reason, i have to borrow a gauge to do it. It really doesn't smoke much though.

I tried making adjustments to the pilot screw (which is in an awesome place) and I've got it to where i think its running the best. When i did clean out the carb, there was a little bit of oxidation/corrosion going on as it had been sitting it really old gas in it for probably 2 year or more. Didn't really do anything more to it but clean it, maybe i should get a rebuild kit?