I've just bought a ratty Yam YQ50 and I've a problem I hope you could help me with. The bike will start but will only run on choke and when it does it revs its tits off, opening the throttle makes it die like its running out of fuel although plenty is getting through. New plug and fuel and I had the carb off all cleaned and blown out but no change... What's wrong? Thanks in advance!!!
you have answered your own question basicly it is running out of fuel and cannot run what you need to do is put the jet size in the carb up 1 or 2 sizes as it will run (just) now and then when you need more fuel for throttle it is starving the engine
I can almost gauruntee that your inlet is split, causing an air leak and revving etc... My mates bike this exactly the same thing the other day and the inlet was knackered
It's a manual choke, I think I've sorted it as it runs ok now but the pipes to the carb as I have it are, petrol, vacuum, oil and the in and out from the cooling system but there's another tube that's connected to nothing which I've blocked and it runs ok, but it must go somewhere??? Thanks for the replies!!
As Fiddyrox said I checked the inlet tube which was fine but there was some crap home made gaskets between the reeds and engine so I made some proper ones and smeared with silicone sealer and made sure the air filter wasn't leaking air and job done!!
