1972 T120 Bonneville prob.

[toz]

I'm sick of trying to find the problem here.

Bike starts and runs ok but revs don't drop immediately when changing gear, it seems to stick a bit, yet the slide is dropping fine. Oh and tick over isn't great.

Had the carb off more times than I care to mention, float is set, jets all clean, timing is ok I think.

Any ideas chaps?

[mark2]

sucking air , sounds like to me

[Revband]

Slide/carb body worn?. Open throttle slightly and feel if the slide moves around.

[toz]

Thanks,......... I must say sucking air is just right I think. Cant see where other than by the slide so I must consider that to be the problem.

Cheers.

[mark2]

make sure the carb flange is flat , take the rubber o ring out , and lap on a lapping plate

[toz]

Ok will do. ta.

[mark2]

the mechanical advance/ret unit is working all good ? no sticking

[toz]

Took it all to bits again, made sure all surfaces were flat, made new gaskets, raised the float just a little...... checked for play in the slide and there is a little bit, hmmm,...... put it back together and she runs like a dream .

I think it was air sneaking in at the carb flange or the bowl. Anyway its sorted.

Thanks.


On another note, I noticed a little oil in the timing housing, it has electronic ignition, could this cause a prob?

[mark2]

I don't think so if its a bit , but the oil seal is easy to change its in the outer cover .

[toz]

Thanks then.