250F Another 2004 KX250F Project/Build

I have a heat gun so I'll try that first.
But if that doesn't work, @PawPaw, just so I have it straight - drill down into the threaded area from directly above, and into the bolt? I have no problems doing so, but can foresee a broken drill bit...
 
No, do not drill down where the bolt is in the threaded part of the swing arm! You drill just past it or about 1" from where the bolt goes into the swing arm. The threaded part of the swing arm extends into the swing arm about 1" so you want to be just past it. You do this so the PB Blaster is able to get onto the bolt threads in the swingarm. You do not want to damage the extended part nor the threads nor the bolt. You see the steel bolt in the alloy swing arm sets up a chemical reaction when moisture is added and causes the threads to bond together and that is what you have to free up for the bolt to come out at all. That is also why you want anti seize on the new bolt threads to stop or slow down this reaction. You can plug the hole later with clean silicone to keep more moisture from entering the swing arm.
The other option is to drill the bolt out and install a "swing arm buddy" into it. Look it up on the internet.
https://www.ebay.com/i/173342952040?chn=ps&var=472053280519

Paw Paw
 
I do have a propane torch as well, just thought that might blacken the aluminum.
Thanks for the clarification @PawPaw. Basically drill the front side and let the PB Blaster seep in from that side, got it.
I'll try the heat first I guess.
I'll let y'all know what happens. As it turns out I signed up for another work contract and I wont be able to ride for at least another 10 days...work sucks and makes B-rad a dull boy.
 
I'm an idiot.
It's quite obvious I haven't turned a wrench in 6 months.
I was sitting there PB Blasting that bolt, trying with my 10mm wrench to break it free, finally my neighbor comes over (and he's not a mechanic at all) and says "why dont you take the wheel off and hit it with your impact?"
Doh!
 
It may break the bolt off. Then you will for sure have a mess. You need to work it out going in and out as needed until you are able to work it out.

Paw Paw
 
It may break the bolt off. Then you will for sure have a mess. You need to work it out going in and out as needed until you are able to work it out.

Paw Paw
Thanks PawPaw. I worked both bolts in and out with the PB Blaster for a few days with the 10mm wrench. Left side budged, right side not so much. But I been turning wrenches for 30+ years now, and I know that the initial "hit" with an impact usually works wonders for breaking shit free. I just didn't think of it.
I'm rusty.
But I wont forget your advice on the drilling from the front side, and will use it if needed at a later date. Preciate it!
As of now, the new chain is on, and I'm hoping to take the kiddo and his yz125 to the track, along with my yz250, and the kxf250 on Sunday. Waiting on radiators and hoses for the kxf, and for US Chrome to get my yz cylinder back to me before then...I had to send it back to them cuz the power valve was binding up. Scott called me this morning and said he would get it done today and ship it asap. Hoping to have it here by Thursday...
 
I was hoping to take her to the track this weekend, but the damn eBay seller of the chinese radiators didn't come through on time. But thats prolly okay cuz I'm having throttle sticking issues. It dont release, binds up.
I've sprayed the shaft side where the cables attach with lube, but she still sticks, especially at the wide open position.
As an aside, I tried to rebuild the carb but one of the float bowl screws stripped the phillips head. But since the rest of the bike was properly taken apart, and the carb was drained, I just threw it together. Obviously i'm gonna have to take it apart again and fix it all.
Either that or get a kill-switch lanyard like they have on jet-skis...lol.
 
Remember that those chain adjuster bolts are not hardened and are very easy to break off using an impact wrench. If and when you do get them out, try to replace them with a hardened grade 8 bolt.

Paw Paw
 
Remember that those chain adjuster bolts are not hardened and are very easy to break off using an impact wrench. If and when you do get them out, try to replace them with a hardened grade 8 bolt.

Paw Paw
Thanks Paw Paw

So next question - Got it all back together, rebuilt the bottom end of the carb, (pilot jet was plugged) only to kick it over a bunch and find I'm not getting spark. Tested the secondary windings and they're 3K ohms higher than spec. So...

Is there a suitable after-market coil, or do I spend Kawasaki bucks for the OE? After spending $12.00 for a main jet at Kelly's Kawasaki I'm not crazy about spending anymore Kawi bucks...
 
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You need to go through your wiring.
I’ve never seen a real electrical failure on a dirt bike. They really do have the basic system figured out. I would go through it thoroughly and check the wiring and grounds.
 
I know they got this shit down to a science, and I dont doubt you, secondary windings specs on the coil are 7.65 - 10.35K ohms, and mine is at 13.75. Primary is in spec.
Straight outta the Kawi service manual...
 
I know they got this shit down to a science, and I dont doubt you, secondary windings specs on the coil are 7.65 - 10.35K ohms, and mine is at 13.75. Primary is in spec.
Straight outta the Kawi service manual...


I would check the tire pressure. It should start right up at 9-10psi.
 
That higher reading normally indicates a bad connection between the plug wire and the metal plug connector in the plug cap. I would unscrew the plug cap from the plug wire, cut about 1/4" off the wire and then screw the plug cap back on and repeat the ohms test on the secondary. I would also spray a good contact cleaner into the plug cap.
If that did not get lower, then replace the coil with an OEM unit.

Paw Paw
 
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