NC21 frame running a NC21 engine with nc24 CDI... PROBLEMS!

[Neosophist]

Ok i tested everything on bike, and all lights and switches is working. Bridged radiator fan and heat gauge and both work. Yet to test fan switch in warm water to see if it will switch fan on. I have yet to plug in the cdi. I removed the clutch cover to see what trigger is used. Its a 2 pickup system 90deg apart and two trigger teeth 180 deg apart. Is this standard on both NC21 and NC24? If not, what is the setup for the nc24. Want to get her running, so i can spend time on the important stuff. Customizing the bike!

yes its the same.

I cant remebere the guy on here but he fitted an NC21 to his nc24 no trouble, just left teh cam sensor disconnected and had to rewire a plug to make use the of the different neutral switch on the nc21, that was the only plug that wouldnt just join up.

i seem to remember you cant do it the other way round though as the nc21 ecu expects cam sensor input

[theZpilot]

Hi Spawn.

Just looking at your dilemma and can tell you I have gone through the same process. I bought an NC21 which I used for 3 years before the motor finally expired when the gearbox let go. I purchased an NC21 engine and then found the one in it was an NC24 motor and the loom had been changed to match it. So began the task of changing it. All the replies you have had so far have accurately pointed out the differences such as the pick up, the extra cam sensor with it's 2 wires and the CDI unit.

I can tell you that a VFR750 wiring diagram is the closest match to the NC21 ignition wiring and proved to be an invaluable reference. I got a secondhand NC21 CDI from a breakers, then purchased some multi-plugs which matched the shape and pin pattern of the existing NC24 connectors (brown ones) and the tool to crimp the connectors (ebay). With these new bits I managed to sort out the CDI wiring and connectors without cutting the existing loom about and got her running a treat.

To cut a long story short, if you still require any help getting it running, give me your email address and I can send you the wiring diagrams, photos of my bike's wiring harness and the modifications I made to install the bigger CDI under the tail unit cover + the all important diagrams and pictures of the wiring changes I made to get her running again.

[Neosophist]

Hi Spawn.

Just looking at your dilemma and can tell you I have gone through the same process. I bought an NC21 which I used for 3 years before the motor finally expired when the gearbox let go. I purchased an NC21 engine and then found the one in it was an NC24 motor and the loom had been changed to match it. So began the task of changing it. All the replies you have had so far have accurately pointed out the differences such as the pick up, the extra cam sensor with it's 2 wires and the CDI unit.

I can tell you that a VFR750 wiring diagram is the closest match to the NC21 ignition wiring and proved to be an invaluable reference. I got a secondhand NC21 CDI from a breakers, then purchased some multi-plugs which matched the shape and pin pattern of the existing NC24 connectors (brown ones) and the tool to crimp the connectors (ebay). With these new bits I managed to sort out the CDI wiring and connectors without cutting the existing loom about and got her running a treat.

To cut a long story short, if you still require any help getting it running, give me your email address and I can send you the wiring diagrams, photos of my bike's wiring harness and the modifications I made to install the bigger CDI under the tail unit cover + the all important diagrams and pictures of the wiring changes I made to get her running again.

The NC21 ignition unit should sit by the battery if you have the proper loom as there is space for it there.

Theres an NC21 wiring loom diagram here http://farm8.staticflickr.com/7376/1187 ... 0738_o.jpg