1980 gs750 idles great runs great at 5k rpm and above

[Guest]

Hi, I just acquired a 1980 gs750e, Vance and Hines 4 into 1, stock air box and all else seems stock. I am having a few issues that if someone could point me in the proper direction, I would appreciate it. I have scoured the forum and can't seem to find the right post so here we go.

When I got it, it would only run on choke. I cleaned the carbs, installed a new air filter, did a compression check, (pretty good) Put new plugs in.

Now the bike starts right up. A little choke for a short period of time and then it idles great. (have it set @ about 900rpm) purrs like a kitten.
The throttle response is very poor to non existent (dies) if it is cold. once it warms up, the bike is good to about 1500rpm then hesitates (maybe misses) until about 4500 to 5000 rpm and then it runs like a mad dog. Pulled the plugs and the were whitish tan. I have eliminated the petcock possibility also. Darn bike runs great above 5000. Really kicks butt.

But it does pop when I let off the throttle. When I did the carbs, I did a bench sync but have not done a carb sync with meters.

All that I have read says needle adjustment. The PO said the bike ran great before it sat this last winter outside under a tarp. Maybe ran great is a opinion. Just looking for some lower RPM power.

Any help would be appreciated.

Thanks in advance.

[Nessism]

Sounds like the pilot jets are plugged or you got the wrong pilots installed. You might want to check the carb rebuild tutorial linked in my signature, and check the Newbie mistakes thread too so you can know what to look out for.

[maintenanceman]

Thanks Nessism.
I'll do that.

[tkent02]

How exactly did you "clean the carbs"?

[maintenanceman]

took the carbs out of the bike, took all the little parts out and soaked them. Sprayed carb cleaner liberally through the carbs and blew the ports out with air. Replaced o rings and gaskets.