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2005 CRF250R Spark issue

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I got my bike from a guy who said it wouldn't kickstart only pushstart. I first took a look at the valves, since honda's valves don't last. They were out of spec so I took the cylinder and head off (I also noticed it had bad coolent pump seal and no coolent :smirk:). It's piston (wiseco 13.5:1) was a little scared I cleaned up the piston and threw new rings in it. One intake valve was cupping so I replaced both intake with prox stainless. I also reground all 4 valve seats. Threw it back together and couldn't get it to fire. I checked spark and it appeared to spark only once every 2 or 3 times it should.

I checked the output voltage of the stator I got 10.5 V ac. I checked the output of the pickup coil and got .1V ac.

I checked the ohms of the stick coil and it's values were a little outside the spec but not too far off.

I decided to rewind the stator with 30gauge magnet wire. I'm hoping that will fix the stator problem. (still waiting on the wire from ebay). What should I do about the pickup coil (or whatever you call it)?

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Ok I rewound the stator. I used 30 gauge wire (it was slightly smaller diameter then stock, I'd say stock is 28). I counted the turns of the stock wire and it had 225 winds per post. I rewound it to have 250 on each post.

It used to put out 10v AC when I was kicking it, now it puts out 17v AC when I kick it. As I understand it's supposed to be putting out 50v AC. My pickup coil still puts out between 0.0 and 0.1 v AC. I hoped it would change.

WHATS wrong guys? any ideas? did I do a poor job wrapping it? has my rotor lost magnetism? does anyone's 250 actually put out 50v when they kick it over? :smirk:

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Another update:

I switched out a pickup coil from one I had lying around. It looked to be the exact same. I put it in and now it gets .2 v. Still no spark.

I switched out the stick coil (the thing the spark plug goes into) from my yfz450 even though the ohm readings were right on my 250f's. Same story no spark.

I have a stator, rotor, and pick up coil coming from ebay. I'll install them and let you know how it goes.

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If you have a bad flywheel, this can cause a similar issue. And there is a no way to check the flywheel either. Replace with new and be guaranteed to eliminate that aspect of your problem.

A lot of of them get damaged by people beating them to remove them instead of using the correct puller - or dropping them...

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Ah hah. Other people do exist on this site.

I put in a used stator and pickup coil I got off ebay. Now it sparks. It puts out 17v ac and .2 v at the trigger.

I have no idea why it works now but it does.

I took it out riding and it worked fine for about 10 minutes of riding, now it doesn't start worth a crap, but still push starts ok. It also doesn't idle well. I figure I'd try jetting it right for my altitude and go from there. I don't want to be chasing down a spark issue if it's already fixed.

The rotor doesn't seem beat up, but I have an extra one that I got with my stator. Perhaps I'll have to buy the tool to get the thing off though. I also rewound my old stator once again, but did a very carefull job this time and did 300 winds per coil (stock was 230 winds). If jetting is right I think I'll install this stator once again and see if that helps it start easier.

If that doesn't help I got another CDI I can try.

Off the subject- I bought a 05 yz450. Fetchin awesome :smirk: no problems at all, starts first kick, has a crap load more power then this 250. I just need this honda fixed so I can sell it and ride my 450. I used to be a CR fan all the way. Now, hondas can go to hell I'm switching colors.

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I'm having kinda hard time jetting it. Stock is 172 main and 42 pilot. I'm not sure if main is right or not, but I put a 175 main and I put a 45 pilot. Just to get it to idle worth a crap I had to back the air fuel screw out 5 turns. Now I'm going to put a 50 pilot in it. Does anyone know why it might need such a big pilot jet??? It has a high comp piston and the 07 dual exhaust. Does that matter???

Oh and my yz450 sheered the rear sprocket bolts and broke a chunk off my rear hub when I was out riding today. Time for a new rear sprocket and bolts. :smirk: All well though it's still a pimpin bike.

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sounds like it's suckin air in somewhere on the intake try to spray starting fluid on it while it's running and double check the timing marks

check that the valve set ,floating "aka vacuum plate" part 14 is installed right I'v seen people put them in upside down http://shop.thumpertalk.com/oem.asp?partcategory=141527&manufacturer=3&category=3&year=2005&model=3345

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