Only running on one cyllinder.

[elbert]

My GT750 will only run on one cyllinder (right one) at low rpms/idle but on all three when the rpm is above 4500 rpm.
I checked for sparks and they are pressent on all three, I have the electronic ignition from Marcel in The Netherlands.
When I hold my hand in front of the left carburator I get fuel on my hand and when I remove it starts running for a few seconds. On the centre carb I get less fuel on my hand and it doesn't start running on that cyllinder.
Any Ideas on what it could be?

[GT500Andy]

How was the situation before you mounted the electronic ignition?
Andy

[elbert]

I had the electronic ignition for half a year and it has been running fine until this weekend. Still runs fine on high rpms.

[rbond]

Sounds like slow speed jets are plugged in two carbs. If not that you may have gotten bad gas that somehow only clogged two instead of all three. There is a smaller possibility that some crank seals are going out too.....just a thought.

[GT500Andy]

Also how is your battery is he fully charged?

[Cliff]

Do you have any vacuum at the carb that's spitting gas?? If you don't, or it feels different from the cylinder that does fire, I'd put my money on crank seals. My Buffalo did the same thing before I tore it down. The cage had broken on one of the crank bearings, which in turn damaged the seal between left and center. Installed new seals and bearings, now she runs on all three and idles at 1100 rpm! And I'm still running with points!!
Cliff.

[elbert]

Battery is fully charged.
I get vacuum at the carbs, not very strong but they are sucking.
Oil level in the transmission seems to be stable, it's not smoking excessively from any of the exhausts.
If the crank seals are shot wouldn't there be more symthoms?

I'll try cleaning the slow jets.