i also posted this in the classics section, but it seems as though it might make more sense to be here.

hey guys, im new to motorcycles, and am trying to teach myself about the engine, and engines in general.

heres the deal.

i own a 75 xs500b. it has been running fine, but yesterday i noticed a slight backfire when i rolled off the throttle.

today, it was even worse, to the point where the engine actually died when i got to work.

coming home from work, i was just wondering if i was going to make it. when i roll on the throttle the engine bogs down and tries to die (or just dies). when i pull in the clutch and roll off the throttle, all of a sudden the rpm's dont drop for quite a while (5 seconds or more) and then once it does die off, it just dies. doesnt want to start. backfires a lot.

im hoping that this is just a carburetor adjustment issue, that its maybe running a bit lean.

any ideas or help would really be appreciated.

thanks.

jeff

also, roughly how much would it cost to get the pressure gauges that you use to sync up the carburetors? i would like to be able to do this kind of work myself in the future.

*bump*

any help please? the only local place that will work on a bike this old is trying to tell me that it has something to do with the alternator/generator, which i think is total bs.

I guess i could see how it could be a firing issue electrically, but it seems to me as though that would happen all at once, not kind of build up over time as this did (oh, and now the bike wont even start).

help!

Hey Jeff,

I had a similar problem with my 75 xs500, it was running fine then quickly was running bad, the idle was all over the place, it almost felt like something was sticking in the carby, had no low range power and was stalling a lot. The problem was point gaps, one was not really even opening, I regapped and shes running great! Hope this helps! Jon