Hi All,

I’m looking for some help/advice. I have 1992 sc28 model. I bought the bike as a project, it was running when I bought it, but had been sitting in a shed for 10 years. I’ve since dropped the engine out tidied it up and now trying to get it back together.

So I have the engine back in, but it’s only running on two cylinders (2&3) and I’m a little lost why the other two aren’t firing. I’ve swapped the wires to the coils over which then makes cylinder 1&4 fire. So it’s not a problem with the coils or leads or plugs, the fuses are also fine and as far as I’m aware everything is connected up properly.

The only thing I can think of is the the wire that I believe goes from ecu to the coil is a little rough where it previous had an alarm wired into it. I’ve tried to tidy it up, but it’s very close to the ecu connector so quiet difficult. The other thing I have noticed is I Removed the ECU, and the pin that powers the coils is a little dull and not a shiney as the other ecu pins. Could it be a problem with the ecu? I’ve attached a photo.

Can anyone give any pointers on where to look next as I’m struggling? I’m guessing a multimeter will help to test the connections, although I’m pretty rubbish with this kind of thing.

Thanks for any help in advance

Will

 

The bad connection. I’ve added more solder to this but not sure if it’s will help

 

I think you can be quite sure that the wire you showed is a problem.
However I think that is not the whole problem. Unless it is a twin spark system which could mean that this one wire is the signal to both coils.

 

According to my manual, there is a blue/yellow for each coil from the ICM. The other wire to the coils is a black/white that is common to both coils. I would believe that the damaged wire is the blue/yellow for the coil that isn't firing.

Mike