900SS front cylinder idling problem

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budgie955
Mariana
Posts: 35
Joined: Wed Feb 22, 2006 11:28 am

900SS front cylinder idling problem

Post by budgie955 »

Just got my 900ss on the road after a 2 year restoration...had it all set up perfectly, but now the front pot will not tick over irrespective of what you do with the air screw or idle screw. You can turn the idling screw full home ..makes no difference. You rev the bike and it picks up fine.
I have stripped the carb and blown all the airways clear, its had new float needles and valves..the valve clearances are fine..the only thing left i havent done is check the float height...
Any ideas anyone?
Over to you guys..

Cheers
Dave Burn

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abmartin
SSD900 Darmah
Posts: 358
Joined: Tue Apr 10, 2007 5:08 pm
Location: New Brunswick, Canada

Post by abmartin »

I have had a leaky float do this. Check for fuel sloshing around inside the float. I presume the throttle slides are correctly synchronized.

Another option is to make sure you are getting a good spark in that cylinder at low revs. An intermittant contact on one of the thin wires leading from the ignition generator can cause this problem.

As well, swap the spark plugs around to see if the problem moves from one cylinder to another. It could be a faulty or dirty plug.

Bruce Martin
1979 900SS
Fredericton, NB
Canada

Lumpy
SD900 Darmah
Posts: 327
Joined: Sun Mar 25, 2007 5:49 am

Lazy pot

Post by Lumpy »

Always worth checking the insulation around the igntion generator wires. My 82 SS had this problem and ran like a pig, although mine was the other way round, idle sorta kinda, run bad. Still worth doing even if the problem is else where. Have since done the alternator wires and they were almost as bad. Worth the effort if your in the area.

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abmartin
SSD900 Darmah
Posts: 358
Joined: Tue Apr 10, 2007 5:08 pm
Location: New Brunswick, Canada

Post by abmartin »

One more thought. If you have the 40 mm carbs, the tickler can jam the float down. Repeated use gouges a small depression in the float which causes it to hang up on the tickler plunger. In my case it made the bike almost impossible to start but I suppose it could create a situation in which the bike would only run on one cylinder at low revs.
1979 900SS
Fredericton, NB
Canada

budgie955
Mariana
Posts: 35
Joined: Wed Feb 22, 2006 11:28 am

Post by budgie955 »

thanks guys...looks like i have cracked it....it doesnt like to warm up on the stand, i took it for a run + it set up perfectly ...now runs like a dream

Dave

budgie955
Mariana
Posts: 35
Joined: Wed Feb 22, 2006 11:28 am

Post by budgie955 »

thanks guys...looks like i have cracked it....it doesnt like to warm up on the stand, i took it for a run + it set up perfectly ...now runs like a dream

Dave

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Geoff
Parallel Twin
Posts: 103
Joined: Mon Jul 26, 2004 11:43 am
Location: London, UK

Post by Geoff »

Great; but sounds like a sticking float if the vibrations of riding make it idle ok.

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