Cylinder misfire/???

JohanM · Post by **JohanM** » Wed Jul 22, 2009 2:10 am

Hi

Thanks for the help on the pick-ups, but it seems like you sort a problem and the next one surface??? Hopefully sometime in the near future I will be able to ride the bike!!!

Want to know if somebody had the same problem and what they did or some advice. I have a 900S2, the fire(think it is) on the vertical cylinder comes and goes while you are riding the bike. When u are riding at normal or full tilt the power will suddenly be gone (running on 1 cylinder). What sometime work is to switch the motor off while you still running, turn the key further to the left and back on and suddenly you can continue on 2 cylinders???

I changed the spark plugs - NGK B8HS, change the resistor spark plug caps, while the bike idles it's got spark and there is petrol from the carburator.

Any ideas before I toss the bike off a cliff?

BEVEL DAVE · Post by **BEVEL DAVE** » Wed Jul 22, 2009 6:13 am

Bad earth??? Seen that before on them.

machten · Post by **machten** » Wed Jul 22, 2009 8:03 pm

Coil perhaps? Try swapping them over and see if the problem moves to the other cylinder. If you are using the original ND coils this is a bit of a pain as you will have to swap the HT leads over as well as they are different lengths. Replacing the leads might be a good thing to do anyway, as it could also be the source of the problem.

conti-mental · Post by **conti-mental** » Thu Jul 23, 2009 9:48 am

Have you tried a different grade plug - I run B7HS on my ss, and I'm tempted to go down to a B6HS.....It always seems to be the rear cylinder that fouls plugs; maybe a result of the different pipe length.
I noticed a while ago that the LH (rear) silencer puts out cooler gases than the front, even when it's totally spot-on.

I'd definitely ditch the resistor caps too

rwhc80 · Post by **rwhc80** » Fri Jul 24, 2009 4:33 am

Johan,

some sound advice above from all concerned but I concur with Conti Mental, get rid of those B8 plugs. for your climate B6HS would be more appropriate.

JohanM · Post by **JohanM** » Thu Jul 30, 2009 7:21 am

Thanks for the many replies. Will probably see if I can find anything wrong with the ignition switch?
I have started checking the electrical circuit associated with the charging, as I have a few problems with the regulators packing up. Does anybody know what is the reading I should get from 1. the stator while it is running and 2. what the charging current from the regulator to the battery needs to be? It is a 3 phase stator. I expected the reading between the phases should be similar, but the readings between the phases were completely different? The readings I got was 120V, 60V, 40V... so the the current to the battery is also lower than what I expected?

The stator were megered. All seems fine, can it be that the phases have fewer windings on as the other?

Thanks for your help so far.

Johan

MartinMille BANNED · Post by **MartinMille BANNED** » Thu Jul 30, 2009 2:10 pm

Did you do a forum search as this topic came up not that long ago, could be anything from, coils,leads,caps,plugs,wire,pick-ups but be most likely your ignitor box

We can all give you advise but not seeing the bike makes it hard for anyone to give the correct answer. Do you for sure which cylinder is breaking down?

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Cylinder misfire/???

Cylinder misfire/???

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