Vintage Dirt Bike Q & A
https://vintagedirtbikeforums.alp-sys.com/

'75 mt125 cdi conversion
https://vintagedirtbikeforums.alp-sys.com/viewtopic.php?f=21&t=2708		 Page 1 of 1
Author:  derekmt125 [ Mon Jun 14, 2010 10:49 am ]
Post subject:  '75 mt125 cdi conversion
i want to swap my points for cdi on my 75 mt 125 elsinore and i just wanted to know what units are compatible and where i could find one. thanks.
Author:  rayivers [ Mon Jun 14, 2010 12:30 pm ]
Post subject:  Re: '75 mt125 cdi conversion
Here's a link to an old thread here that may help:

viewtopic.php?f=21&t=1674&hilit=

According to this the stator and rotor will bolt right in, with the coil and CDI box requiring some work to mount to the frame (I did this on my MR, it wasn't too hard).

I've bought a number of complete ignitions off eBay, and paid from $68 to $120 each including shipping. I was very patient and waited for the best price, though; if you need yours right away, expect to pay more. Any '74 to '78 CR125M ignition should work providing the stator and rotor numbers match (examples are 4B 360B, 6A 400, 7H 400, etc.) I have a 5K 400 stator/rotor set I could part with; the rotor has just been remagnetized, but the stator has some rust on it (many of them do).

With a CR125M ignition (set at 2.2mm BTDC), pipe, and carb on a stock MT125 cylinder, your MT should perform a lot like a CR125M up to maybe 6,000 rpm or so, and will continue to pull much harder than a stock MT above that.

Try searching this site, I wouldn't be surprised if there's even more info available.

Ray
Author:  derekmt125 [ Mon Jun 14, 2010 10:38 pm ]
Post subject:  Re: '75 mt125 cdi conversion
Great! thank you so much. i would also be interested in purchasing that cdi from you if you think it will work.
Author:  rayivers [ Tue Jun 15, 2010 10:05 am ]
Post subject:  Re: '75 mt125 cdi conversion
This stator was on my bike briefly recently during troubleshooting (when I found out about the matching stator/rotor numbers :)) so I know it works, and I just checked it again with the meter to be sure. The rotor has a few marks on the back side from using a bearing puller (pretty much the only way to get them off unless you can find a super-rare OEM Honda puller), but it works like new.

Bear in mind that you'll also need the CDI module - here's one that's pretty reasonable, and there are plenty more on eBay:

http://cgi.ebay.com/ebaymotors/igniter- ... ccessories

I'd highly recommend using a CR125M coil too, which is much larger, has no condenser (the CDI unit won't want to see a condenser on its output), and will plug right in to the CDI output cable instead of having to be cobbled together. Here's one I found that looks OK (NOTE: 2 out of 5 coils I've bought on eBay had bad plug caps, which are easily replaced):

http://cgi.ebay.com/ebaymotors/1974-Hon ... ccessories

I'll send you a PM about the parts.

Ray
Page 1 of 1 All times are UTC - 7 hours [ DST ]
Powered by phpBB® Forum Software © phpBB Group
https://www.phpbb.com/