Motorcycle Repair: cant give gas or else it dies and back fires, yamaha sr500, cylinder motorcycles

Question
I know this is not your specialty but i have a 1978 yamaha sr500. but i think my question is general to all single cylinder motorcycles. It has been running ok, just finished fixing all the kinks after 21 years of storage, or so i thought. every time i give it gas it seems to kill it, it idles ok on just choke but even on choke if you give it gas it backfires and almost kills it or does kill it. i already took out the jet and cleaned it but i'm thinking it could be the accelerator pump? any thoughts?

Answer
Hi Kevin,  I do not know if the sr500 has an accelerator pump, but usually the carb does have a primary and secondary air/fuel circuit and it sounds like one of the two is still partially clogged.  Check the air filter, and the exhaust also.

Good luck,  Jan