Xr650l Icm

Self induced problem I think--weak battery, cold day, my battery charger has "engine start" function which I used. 2000 XR650L

Bike was running excellent previous. After starting went for a short ride and it was missing in upper RPM range but would "catch" letting off the throttle. Good to 55mph or so. Initial thought was bad gas. Drained, refilled, battery still weak, used start function again on charger--now bike will start and idle, as you open the throttle it goes real flat even at full throttle and will not rev over maybe 1800rpm--no tach so I'm guessing. Can ride, but cuts out when you try and accel--as long as you are below 1800rpm or so it is OK at best. Tests done:

All ohm checks by manual are within specs, coil, signal generator etc

Leak down is less than 20% at 20psi, 0 above 25psi

Cranking compression is a bit low but altitude is high--above 6000

New plug

Inductive timing light will not pick up and work--light is good--checked on another vehicle

Ground plug to frame and crank engine--spark appears to weak and erratic

Can't explain the inductive timing light not picking up as plug is firing

Conclusion: ICM was partially damaged by using battery charger in start function but did not have total failure. Advance not working and possible that initial timing is off too. That is why I wanted to check timing but no go.

Anyone seen this before? Thoughts?


Welcome to TT. I believe its the cdi ignition box that you are refering to, If you have a bad battery that could be your trouble, or your stator may be bad, (not charging or putting out enough voltage for spark). I do not see a battery charger really breaking anything. I believe you had a deteriorating electrical issue beforehand.

After thinking on this a while, your problem could also and most likely be caused in the rectifier, and that a "jump" start could indeed burn a diode in the rectifier, I believe there are six total (diodes) and as much voltage as the ignition system uses a failure or partial failure would cause the problems you described, with I would call an intermittent voltage problem, or low voltage. When you ask the motor to accelerate the volts to the sparkplug should also ramp up and it seems they are not which causes the engine to sputter. Question is do you have a manual? In it you will find how to test the rectifier.

Good luck, I will look in my manual and see what I can find. Post your findings or further questions on this thread. :thumbsup:

Thanks for the thoughts--but I have checked both the rotor and stator as well as the recitifier unit. All are in spec according to the factory service manual chart--using my digital Multimeter. I've got a ICM (Honda calls it an ignition control module at least in this application) coming so I should be able to R2 the unit early next week and give it a try--this time without the start function on the battery charger.


Yep, you are right Honda calls it an icm, my bad. Just make sure your battery has a full charge, after you swap out the icm.

To rule out a carb/fuel issue, try turning the choke on and see if it'll rev higher.

When I suspect water, I drain the bowl into a clear glass (just like pilots do).


Got it running again just as it was before. The ICM was in fact bad, but still working. It was not advancing properly and thus the inability to rev. Put in new ICM--problem solved. Keep in mind that it was working properly before I jumped the bike with my start function on the battery charger. I'm 99% sure I was the cause of the problem--I will not use the jump start function again. Also I got the ICM for about $100 from http://hondapartsdirect.reachlocal.net/fiche_select.asp

which was significantly better than any other price I could find.

Thanks for the update! Also thanks for the link, this is what TT is all about!!!:lol: Now get out there and ride:ride: Happy Holidays

Welcome to Thumpertalk, Off-Road......:lol:

:confused: :confused:

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