Hi everyone! I'm new on this forum, but I am part of a few others so I know my way around a little. Anyway I got a 1974 MX250 a while back and it wasn't running when I got it. I have it stripped down, frame and engine re-painted and put pack together but now I'm trying to get it to run. The problem I'm having is I have the inner rotor type ignition system, which requires an 8 wire CDI, but the CDI on the bike is for the outer rotor system which only has 7 wires. I've read time and time again that you can make them work just by grounding the extra lead off the ignition, but the wiring has been messed with so much that I can't tell what's supposed to go where. Has anybody done this? Once I get some spark out of this thing I'll be set. The carb has been re-built so I should be able to just fuel and go!

Hi everyone! I'm new on this forum, but I am part of a few others so I know my way around a little. Anyway I got a 1974 MX250 a while back and it wasn't running when I got it. I have it stripped down, frame and engine re-painted and put pack together but now I'm trying to get it to run. The problem I'm having is I have the inner rotor type ignition system, which requires an 8 wire CDI, but the CDI on the bike is for the outer rotor system which only has 7 wires. I've read time and time again that you can make them work just by grounding the extra lead off the ignition, but the wiring has been messed with so much that I can't tell what's supposed to go where. Has anybody done this? Once I get some spark out of this thing I'll be set. The carb has been re-built so I should be able to just fuel and go!

OOOh, welcome to the forum, could be a bit till a response comes up, maybe a day or 2. There are a couple of lads on here that should be able to set you right though. 75cc too much for my knowledge. Sorry.

Thanks! I have found some guys with the correct CDI on ebay and stuff, and the one I have is in great shape so I might see if they're willing to trade. The coil on the bike is also wrong which might be part of the issue. I might do a new coil, wires, caps and plugs then try playing around with the wiring a bit more. It's cheaper than buying a new CDI. I think I'll fix up the plastics on the bike the best I can but then get a new set (from DC plastics?) for more show. The bike will look great, and it is a 74 twin shock so it qualifies for vintage racing!

Where you based Stellar " Speedshop [ on here,& ebay] is a Wizard in CDI. ask him politely ,,

Oh " i see you have a Z400 , They were slower than a Glacier

Where you based Stellar " Speedshop [ on here,& ebay] is a Wizard in CDI. ask him politely ,,

Oh " i see you have a Z400 , They were slower than a Glacier

Speedshop eh? I'll have to keep that in mind. I'm located in Guelph Ontario, about 40 minutes from Toronto.

The KZ400 didn't run when I got it but it had decent compression, still haven't done much riding with it, but it's just an in-town/go out for coffee kind of bike. I doubt it'll do the ton, but that wont stop me from trying it sometime!