[mattlloyd50]

hi i have an swm 240 and have had some ignition trouble.
it would run fine for about half an hour then would stop sparking, i have replaced the complete ignition system (stator winding, condenser, points, ht coil and plug).
this has solved the problem and it ran fine for two trials but during the most recent trial it started misfiring on a long climb.
since then it will start and idle ok, but when i ride it splutters and backfires a lot.
could this be the condenser breaking down?

i have also cleaned the carb and tried a different clean carb but no change in the symptoms. so im pretty confident its not fuel related.

please help as im very frustrated with it.
thanks

[Tayld]

Do not laugh but is it your petrol?
We had very similar problems with a Montesa 349. It was ridden in two different trials over the same weekend, on the Saturday the bike was great and on the Sunday it was pants! The only difference was the petrol, Saturday's petrol came as usual from the local Total garage, because the local gaarage was not open Sunday's fuel was bought from a major supermarket's own pumps. The supermarket petrol had water in it straight out of the pump! Cleaned the carb and tank, refilled with our normal petrol and the problem vanished.

[B40RT]

mattlloyd50, on Jul 30 2010, 10:54 PM, said:

hi i have an swm 240 and have had some ignition trouble.
it would run fine for about half an hour then would stop sparking, i have replaced the complete ignition system (stator winding, condenser, points, ht coil and plug).
this has solved the problem and it ran fine for two trials but during the most recent trial it started misfiring on a long climb.
since then it will start and idle ok, but when i ride it splutters and backfires a lot.
could this be the condenser breaking down?

i have also cleaned the carb and tried a different clean carb but no change in the symptoms. so im pretty confident its not fuel related.

please help as im very frustrated with it.
thanks

Remount the condenser by the coil, so much easier to eliminate such potential problems.

Is your fuel flowing fast enough ? Had the same symptoms and was down to faulty fuel tap.

[MotoVintage]

if your condenser is going bad the contact points will become concave & convex,

[mattlloyd50]

the fuel system seems fine, even the filter on the fuel tap in the tank is clear.
im going to try a different condensor tomorrow hopefully.

[Stork955]

Gday, what colour is the spek plug? Check this first. It may save a lot of time.


Cheers,

Stork

[mattlloyd50]

thanks for the help and replys.
i swapped the condenser and the problems gone.
if it happens again i may fit it away from the engine.