Jump to content
Sign in to follow this  

XR100 CDI conversion

Recommended Posts

We finally got my son's 1991 XR100 running right. We got a used coil and magneto stator from Ebay and installed them. It still didn't run right, so I used my weak strobe-type timing light to check the dynamic timing (I had set it static already). Turns out the springs were stretched on the centrifugal advance, and it was basically fully advanced all the time, including when I set it static. Thus there was no further advance kicking in when the RPM's climbed up. I bent out the outer spring hooks to create more tension in the springs, and it runs much better now. Of course now I have no idea whether the advance is coming at the correct RPM.

So it appears there was never anything wrong with the old stator and coil.

At the same time, I won an auction for a 1995 CDI magneto (sorry socalxr). I guess I'll go ahead and install it, but I have a few more questions.

I've already gotten the advice from this forum about the stepped woodruff key and grinding away the crankcase for clearance.

What I received is the stator, flywheel, magnetic pickup, and harness. The other end of the harness has two bullet connectors exactly like the original points ignition had. But do I use my old coil? Or do I have to get a CDI box like I see all the time on Ebay for $50 or so?

Are there any other OEM parts I need to make this work?

Also how do you set the timing with this CDI? The magnetic pickup attaches with one pin (like a pivot) and one screw. It doesn't look like there's supposed to be much if any adjustment there. So is the timing mechanically fixed this way?

Finally what about centrifugal advance? There's no weights or springs inside the flywheel, so how does it handle the timing advance?

As usual, there's more to this ignition stuff than meets the eye...

:cry:

Regards,

Peter

Share this post


Link to post
Share on other sites

Before anyone wastes a lot of time listing the parts, I did my homework and found what I needed to know from the parts fiche. Even at ServiceHonda the coil and harness would be about $85 (including the rubber mounting things). I guess I'll wait for these items on Ebay as well.

Researching the ThumperTalk archives I learned the aftermarket rev boxes are basically OK to use and save money over the $90+ OEM box (again, ServiceHonda pricing).

After inspecting the parts fiche image I'm left wondering how the rubber mounts attach to the frame. Do they use the same threaded holes as the older points coil did? Or is there yet another bracket I need to find?

Regards,

Peter

Share this post


Link to post
Share on other sites

At the same time, I won an auction for a 1995 CDI magneto (sorry socalxr).

Thanks a lot! :cry: Just kidding, I won a cdi and harness, there was a coil for $19.99 buy it now.

That interesting about the springs being worn. That would explain all those points motors running like crap after about 15 years and all the stator, condenser, coil, and points changing never helping.

If possible go a head and get the stepped key, but I run mine with a regular key with no problems. I just line it up and tap in place with a mallot, then impact it. It's never moved. CDI's are the best, you'll be stoked when you get it completed, just kick and it starts and revs with no problem. :cry:

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

Sign in to follow this  

×