SR125 misfiring

[Tentpeg]

Hi all,

I've just bought a '91 Yamaha SR125 to learn on, and it is misfiring on occasion, and quite often "chugs" along and doesn't seem to catch; on occasion this has caused it to stall. I do get a rather exciting backfire every now and again too! This doesn't happen all the time, and for the majority of it, the bike runs fine!

I'm a technical idiot, but I've had a friend look at the carb, plug, fuel line etc and all seems tickety boo. the only thing he found was that the carb intake hose was a little cracked & weathered and looks like it needs replacing, would this be what is causing the problem? and if so, where could i get a replacement one?

Many thanks, great forum by the way!

[prawny1]

could be a duff/dry battery, i had a little hyosung years ago that behaved like yours, the battery was dry so i topped it with de-ionised water up and it behaved itself until i replaced the battery a few months later(was selling the bike and didn,t want a scream if the bike started playing up),

funnily though it started off the button every morning even with a bone dry battery.

[Tentpeg]

thanks for that prawny, i'll have a look at that!

[Tentpeg]

An update on proceedings! The carb hose is new, battery all ok and the carb as said above is fine, as is the spark. I am at a complete loss now. The problem is still there....HELP!

[wizz99]

Hi Tentpeg , did you manage to find out what the problem was as i am having the exact same problem with my SR .

cheers Wizz99

[paddlesat16]

you could be overfueling, take out the spark plug and check it's colour. wet and black your running rich, light brown is perfect, white and crackle glazed too lean. Simples..
____________________
I once saw a bloke shagging a donkey.... in Saudi arabia. Theory Test Passed 26/10/09 Mod 1 Passed 26/4/10, Mod 2 Passed 7/6/10 Current Bikes Suzuki GSX1400 K5, Aprillia Pegaso 650, Suzuki DR350T.