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hello

i have a crf 450 2008 looking for some advice on, basically my bike has no spark and no voltage coming through the ht lead, i have had the stator refeshed and made no difference any ideas would be very helpful thanks

I'd probably start with checking continuity/resistance on the coil, plug wire and the grounds. Check for loose connections on the stator wires or broken wires.

Make sure your kill switch button isn't damaged and grounding out too!

the plug wire has continuity.. also i have unplugged the kill switch

I'm going to revive this thread because I have the exact same problem with my 2002 CRF450R. I have no spark. I disconnected the kill switch; tried another (used) spark plug; tested the primary and secondary coil for continuity and resistance; made just a quick cursory inspection of the wiring harness and connectors. I rode yesterday for a couple hours, stopped for lunch for about 30 minutes, but the engine never fired after lunch. Didn't crash the bike, just put it on the stand. It's as if something happened during my lunch break. I'm going to replace the spark plug with a new plug before I go ballistic but I already tried a second used plug with the same result. It's not the coil or lead or cap. I get a good continuity test, per the manual, even with a spark plug in the cap. I've got a manual with the ignition system troubleshooting procedure, but don't have the capability for all of the diagnostic tests. Any similar experience out there?

No similar issue , but , have you checked the ICM ? (Ignition Control Module) , if your getting power out of the stator , but not to the plug, and your sure the coil is good and all grounds are secure , i am guessing the ICM is the culprit , try sticking the ICM in the freezer for about 5 minutes , then hook it back up , if the bike starts right up , then once its warmed up it dies then i would bet the ICM went bad

JimDirt, the ICM troubleshooting on page 160 says "... it may be difficult to check ICM by itself. Therefore, testing is by the process of eliminating other causes." But I like your idea, and I may try it. Here's another test result that I need someone to check for common sense or if I am misinterpreting something. First, I've got the wiring harness on the workbench and continuity tests good on all pins. There is a throttle position sensor test on page 163. My results seem opposite of what the book is saying. Resistance between blue and yellow wire terminals for the throttle sensor is 12 to 13 K-ohms with the throttle closed. As I open the throttle, resistance decreases to 4 to 5 K-ohms. The Japanese to English translation of the manual may be losing me, but isn't the manual saying that resistance should 'increase' as you go to full open throttle?

I read BLUE and BLACK 4-6

YELLOW and BLACK is when you work the throttle
Closed to Open = UP , Open to Closed = DOWN

That's what I thought too, JmDirt. I'm getting the opposite results. Hard for me to believe the throttle sensor failed in such a way that the numbers are right but the trend is opposite.

The bike will run fine without the TPS , it is tied to timing (kind of like a vacuum advance in a old Chevy distributor) , but the bike will run without it and it wont cause issues with spark

And in your prior post you mentioned Blue and Yellow , not Blue and Black or Yellow and Black which are the colors mentioned in the manual which is what i posted above

Ok, we may be getting closer to explaining my ambiguous multimeter results. My manual, in the procedure for testing the TPS, makes no mention of the black wire. It says measure the resistance between the Blue - Yellow. Would you mind PM me your email address and I'll send you a jpeg of page 163? I don't think I can attach an image here unless it is hosted on some website. Maybe you know a work around to do that. If not, no bigee. I've already taken enough of your time.[/img]

This is from my 08 Service Manual

'08 must be different then '02. How did you upload that image?

So you are using a 02 Service Manual ??? , if so yes the wiring is different , as i have a 02 and the manual for it as well and they are clearly different (i do not have a 08 , just the service manual , as well as manuals for 250R/X and 450R/X for different years , and CR250) and YZF's ,YZ's WR's, RMZ, KTM 250/450 300 2 strokes, and Kawi 125's/250's,250F/450F's

To upload a pic i use Image Shack , its free and holds a crap load of pictures , i think you get 5 gigs of space , most pics are at or under 1 mb , so you can upload thousands of pics , then i copy the link and paste in the forum (some other forums you have to click on a link icon then paste your pic link to that)

CRF's Only requires you to "host" your pictures on a site rather than directly uploading from your PC , which some forums allow , but i believe its a bandwidth issue , so i would rather have a faster loading forum then the ability to upload directly from my PC

I also use Adobe Photo Shop when i use Print Screen on my PC , then adjust the pic size as i need in Photo Shop then upload it to Image Shack , though this site (CRF's Only) limits the size of the pic automatically and adjusts the size to fit in the topic , as i tried to make it larger , but it kept resizing it when i hit Submit , but when i looked at it in Preview it was the size i wanted , but otherwise , its pretty easy and straight forward

Cool, thanks. I saved your last post for future reference. I'll try Image Shack.

Meanwhile, sounds like you've got the '02 Owner's Manual so you should be able to see exactly what I'm seeing on page 163. I am referring to the Owner's Manual that came with the bike.

I ordered a new coil and spark plug cap. I don't know what I'm doing wrong testing the TPS but I'm thinking it shouldn't prevent the bike from starting. I'd be interested to see the applicable page of the 'Service Manual' for the '02 CRF450R and compare that with my page 163. Anyone got that?

That is what mine is , its the Factory Service Manual , and it still does not say what yours says and its on page 303 in mine , here is a pic of my 02 Service Manual