It also may be possible to get the AC power from the KLX250's magneto/alternator. This outputs three phase AC, by tapping off of any two yellow wires (which go to the regulator), this may provide the needed voltage.

To be sure, we would need someone to measure the AC voltage coming off of the KLX300's magneto (at the Red and White) wires and compare that to one phase of the KLX250's.

This option may have the best chance of working.

 

How's it going vfr.......we want an update.

 

This has been one of those weeks from Hell! I haven't had a chance to work on it.....maybe this weekend.

 

Gary,

Where's this on your "to do" list? I'm curious because I may give it a shot myself, but if you're close to looking at it again, I'll hold off. I've seen some KLX300 ignitors on ebay and Shadetree speculates that a different ignition curve may be able to boost the big bore.

 

Sorry, right now the "to do" list is growing from the top down. The KLX is running so good that I haven't had the cdi as a priority. I know, I've failed you guys. []
Now that the weather has straightened up I don't want to tear anything down and miss some good riding!

 

"Failed??" Seems to me your priorities are spot-on.

1. Ride
2. Ride
3. Ride some more [8D]

When in doubt, refer to rule one.

 

Just won a KLX300 CDI off of eBay for $33.62 including shipping.

I'll try to pick up where VFRpilot left off. I think that I have things mapped out pretty well,one concern is getting power, either 12VDC off of the electrical system or I'll tap a phase off of the stator.

Another concern is that the pickup coils are compatible, I'll guessing that they are.

 

Just an update on this experiment.

Hooked up the KLX300 CDI the way that I outlined in a previous post. Took power from two yellow outputs from the generator (and later from the regulator's output). Measured the two yellows as 11-13 VAC

Couldn't get a spark. I want to verify that the CDI is good, so I may hook up a stand-alone jig to test it.

Assuming that the CDI is good, I'm afraid that the pickup coil on the 300 is different from the pickup coil on theKLX250 - not surehow to tell. What I really need is an o'scope to look at what's coming out of the pickup coil.

I haven't given up on this yet...

 

i guess we gave up?

 

More than one guy has tried and failed.

It's really not the most sound of ideas anyway. Most motorcycles that use that type of CDI have a stator coil dedicated to ignition only and separate coil to handle lighting/electrical loads.

Picking off power prior to the reg/rectifier on a system designed to have the entire 3 phases of 39VAC rectified and regulated prior to powering any load is just asking for touble down the road, if not immediately.

The only thing suitable for the KLX250S electrical system is a 'DC' CDI. I'm currently running a KLX250ES DC CDI with 35 Deg BTDC @ 5000RPM. You end-up with a bit more spirited acceleration, but the 'bang for the buck' is very low. I think I paid a combined $350.00 US for the CDI, mount and wiring adapter. The most noticable performance mods, by far, have been the big bore kit and the pumper carb. Best bang for the buck was the uncork and after market ehaust.

My advice would be to not chase this thing like the Holy Grail or you will be disappointed. You have to do a lot more than bolt-on performance mods to the KLX in order to take full advantage of the increased advance.