Mid range running issue

[Guest]

Well my 1980 750E is running poorly in the mid range. Got it out from winter storage and all was fine. Filled at the local station and that is when all of my trouble started. I drained the bowls and the tank and filled with fresh gas, new plug, and a new fuel filter. Same issue. the bike breaks up in the mid range. Idles fine and runs fine on top. At around 4500rpm the trouble starts and it starts to clear up around 6500rpm. What gives. I really don't see a reason why I would be having these issues. Ran fine all last year and was fine when I took it out of storage. Any ideas?

[hikermikem]

Sticky slide(s) perhaps?? Try some seafoam in a tank of gas and see if it straightens out...

[doug g]

I could give it a try but I have my doubts about sticky slides. Bike didn't sit for long and the fuel was treated with sea foam before it was parked for the winter.

[850 Combat]

You drained the bowls after it sat all winter, not before, right? My guess its the usual gummy carb syndrome.

[doug g]

after the winter break.