750T - Ignition

5 - 4 - 3 - 2 - 1 - uh?

We seemed to be so close to firing up the beast. We have a regular spark at one plug but only one - literally one - at the other. When the starter motor is energised, one plug sparks regularly, but the other sparks once and then does nothing.

We believe that both plugs and both coils are OK. Both plug/coil combinations work when connected to one of the ECUs, but not when connected to the other ECU. We have concluded that we have a dodgy ECU (I am sure both cylinders were firing before the bike was dismantled, so that’s a puzzle).

Is there any way to test the ECU?

Does anyone have a used, working ECU that we could buy? I am sure you all know how much a new one would cost!

Steve Kuntze

Not sure whether you can try this but have you tried physically swapping the ECUs over in case theres a poor connection to the unit itself, at least this would confirm that the ECU is dodgybefore laying out money. Finally could both units be tested simultaneously (on the bench) to detect if there are any differences between them (testing between pins or to earth etc. with a multi meter). My comments are only general as I have no experience of this model but buying a new ECU seems like an expensive option and needs to be a more definite diagnosis thandodgy`.
You will have gathered that I am tight when it comes to laying out money :laughing: :laughing: :laughing:


Thanks Chris, I will try your suggestions.


By a process of elimination we established that we did indeed have a faulty ignition unit. It was fortunate that one of the units was OK, as we could use it to confirm that both sets of plugs and coils were working.

Gutsibits came to the rescue with a new Motoplat unit and we now have a sweetly running 750T.

Great result :smiley: