Troubleshooting Dual Spark ignition

[wood-d]

I had noticed a gradual degradation in the performance of my bike that began in the Spring. The symptoms were:

o Rough idle
o Poor acceleration from a stop
o Really bad surging – difficult to maintain a constant speed through residential areas


I started with the fuel system. I changed the fuel filter and saw no change in the performance.

The second step was the air supply. I removed the filter and discovered oil in the air box. This is not an uncommon problem. I cleaned up the air box and installed a new air filter. This has no effect.

I then started on the ignition system. The first step was new spark plugs. This made a world of difference. The bike ran considerably better, but there was still a stumbling at idle and difficulty accelerating from a stop.

I decided to fabricate a fixture to allow me to test the spark plugs individually. The red wire has a clamp from a battery charger attached to it so the fixture can easily be grounded to the bike, to protect the ignition system AND YOU!!




One by one, I connected the plugs to the fixture and started the bike. As it turns out, the main plug on the right cylinder was not firing properly. With that plug connected to the bike ignition and the secondary plug connected to the fixture, the bike was difficult to start and would stall very quickly.

I thought this might be helpful to someone, so I thought I'd post.

[roger albert]

Nice job and pix. Thanks for sharing.
I assume it's all good now?
If it wasn't the plugs, was it a wire?

[wood-d]

Originally Posted by roger albert

I assume it's all good now?
If it wasn't the plugs, was it a wire?

Yes, all is very good. The problem was the ignition coil was bad. #3 in the picture below. Not an inexpensive part.

I'm not sure if the new plugs were actually necessary, but it ran a whole lot better once I installed them.

[repoe3]

Originally Posted by wood-d

One by one, I connected the plugs to the fixture and started the bike. As it turns out, the main plug on the right cylinder was not firing properly. With that plug connected to the bike ignition and the secondary plug connected to the fixture, the bike was difficult to start and would stall very quickly.

I thought this might be helpful to someone, so I thought I'd post.

there is a recall for the twin spark resulting from the way the O2 sensor and the right side ignition wires were run, causing resistance and all the symptons you describe.

i thought i had dealt with mine when i installed the PCIII, yet it came back ina big way recently. i rerouted the wires as best i could and also noticed the main power cable was sliced into by the battery tray. cleaned that up and she runs better than ever at 55k miles with the fuel filter and spark plugs in need of replacement. so be on the lookout if the bike starts to do the same thing, it could be the wiring, not the coil.

repoe3

[SergioK]

My electrical grounding knowledge is a bit fuzzy... you ground the spark plug to a battery charger? Do explain.

[wood-d]

Originally Posted by repoe3

there is a recall for the twin spark resulting from the way the O2 sensor and the right side ignition wires were run, causing resistance and all the symptons you describe.

repoe3

Repoe3, is this a recent recall? My bike received a 12K from the dealer Sept 07. If the recall was out then, it should have been done.

[wood-d]

Originally Posted by SergioK

My electrical grounding knowledge is a bit fuzzy... you ground the spark plug to a battery charger? Do explain.

You ground the spark plug to the frame, which is connected to the negative terminal on the battery. The battery charger comment was the style of clame. Here you go:

[repoe3]

Originally Posted by wood-d

Repoe3, is this a recent recall? My bike received a 12K from the dealer Sept 07. If the recall was out then, it should have been done.

the recall was issued back in 03, but assuming the dealer did it, without informing you, or noting on a service ticket...well, you know what they say about when you assume, right

just something to keep in the back of your mind should you see any other such symptons. you described EXACTLY what i have been experiencing for a long time, on-again, off-again sort of thing. if you had said it was the left side, then it was less likely the same issue, but the right side; seems a bit of a coincidence.

either way, your bike is running great now, you did a heck of a systems check, and are now ready for many more miles of riding. thats how i look at these sorts of things. just about to roll over 55k on mine and she doesnt feel odl or worn out. of course the ohlins probably help with that.

repoe3