Vintage Dirt Bike Q & A

I just picked up a real nice '79 CR250R and I have a question about the different ignition systems used on these bikes. When the previous owner got this bike it didn't have any spark. He picked up another motor and CDI at a swap meet and changed the CDI and the bike fired right up.
It starts and runs great, but as I was looking over the other motor and the box of parts I got with the bike (including the old CDI) I noticed the spare motor has a "C" on the ignition cover and the original cover on the bike and the old CDI have an "E" on them. I haven't taken the tank off the bike yet to check, but I assume the CDI he put on the bike is a "C". I know from everything I've read that these are supposed to match, but my question is, will running the bike hurt anything until I find an "E" CDI or swap the other stator/cover (and hope it's good)? I'm not racing the bike at all, or even riding it very hard for that matter. Just taking the occasional spin and having a little fun like I used to years ago. Thanks for any help.

Not at all. All ignitions are interchangeable, but your engine will
run best when you have a matched set.

By the way, the "E' ignition is the one to have.

dogger

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1973 CR250M
1979 CR250R
1993 CR250R
2008 CR500R
2009 CR250R

Thanks dogger! That's good to know. I'll keep an eye out for an "E" CDI to match my stator. Thanks again!

Hey Dogger , Any specifics on what makes the E better ???

The various ignition codes were due to production variation as the ignition controllers and
stators were produced. The codes allowed Honda to match ignition controllers (CDI), with
stators during assembly. Of all the codes, it appears the "E" code variant was the one that
most closely matched the optimal original map.

The coding is similar to what Honda did in later years to match pistons and cylinders (A & B),
that were produced at different plants or in different runs.

Hope this helps.

dogger

_________________
1973 CR250M
1979 CR250R
1993 CR250R
2008 CR500R
2009 CR250R