Do I need to rebuild

[muskrat]

I bought a 81 GS750L di an comp. test 1,3,4 read 125 p.s.i. #2 reads 75 p.s.i , I am just wondering. The bike was sitting for about an year with out running. It dose run just very lean (no mufflers or air cleaners).

Could anyone help?

[Roadwarrior]

My guess is that the rings in that cyclinder may be stuck. Running without the header will burn your exhaust valves.

[rphillips]

A tight valve is the first thing I would look for, if I find low compression, there are 4 on your # 4 cyl.

[muskrat]

When I bouhgt the bike the guy i got it from had the ext. cut off already.Just test run for about 1min. I bought new ext. for it.

thanks for the reply!