250F Another 2004 KX250F Project/Build

Okay here she is, just picked her up yesterday.
Another basket-case that I just couldn't say no to.
Now it's time to become Sherlock Holmes again and piece this baby's history back together, find out who she is, whats been done to her, and what's left of her.
I dont even know her name yet...
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Today I took some time to see what I got in this box of chocolates.
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Looks to be complete, or at least +90%.
Came with the service manual, a Blue-Point digital dial caliper, triangle stand, some snazzy carbon fiber shields and skid plate, pro-taper bars and an Applied upper triple-tree clamp, and some ASV levers.
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I also have a $180.00 invoice from a local bike shop for 1 bearing and R&R time. Bearing number is 09240160, which if I'm correct is a Hot-Rods crank bearing that is inside the Hot-Rod connecting rod it has.
Dude said he rebuilt the lower end...

The only glaring problem I have seen thus far has been the broken aluminum threaded thingamajiggy seen below;
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How bad is this? Bring to a weld shop and have them fix?

After having sorted through all the pieces, the question is, what to do first...?
What do y'all think?
 
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Nice find. They tend to over heat so boyesen water pump and impeller with engine ice.
You might be able to weld and retap but probably better to find another set of cases.
I heard you have a manual.... dont cut corners or it will be in pieces again. Especially this model year.
 
Nice find. They tend to over heat so boyesen water pump and impeller with engine ice.
You might be able to weld and retap but probably better to find another set of cases.
I heard you have a manual.... dont cut corners or it will be in pieces again. Especially this model year.
Well if that's not a warning I dont know what is!
It does have a Pro-Circuit water pump. Also has a new set of cam chain guides.
 
Well if that's not a warning I dont know what is!
It does have a Pro-Circuit water pump. Also has a new set of cam chain guides.
That's a good start. Also can chain tensioner needs to be replaced. They had issues and ppl were changing them like crazy.
 
Krieger manual cam chain tensioners. I'll have to call him for another...

I don't know what they recommend for that bike so you'll have to research it a bit more. I thought they had an auto adjust one they used.
 
I've got some time for this project now and the first thing that I am thinking about here is that broken piece;
Broken.jpg
What do you guys think is the best option here?
1 - forget about it, run it as is, and wipe off oil after every ride
2 - have it welded somewhere, then drill and tap
3 - buy another left side crankcase
4 - other..?
 
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the overheating isn't the only issue, I'd do SS valves, and if I'm not mistaken they had ignition issues (coil/ignition box)
 
I've got some time for this project now and the first thing that I am thinking about here is that broken piece;
View attachment 30922
What do you guys think is the best option here?
1 - forget about it, run it as is, and wipe off oil after every ride
2 - have it welded somewhere, then drill and tap
3 - buy another left side crankcase
4 - other..?

That's a cylinder mounting bolt so I would try to weld a piece then tap or get new cases. Cases would be my 1st choice.
 

SRAD97750

Moderator
Staff member
I've got some time for this project now and the first thing that I am thinking about here is that broken piece;
View attachment 30922
What do you guys think is the best option here?
1 - forget about it, run it as is, and wipe off oil after every ride
2 - have it welded somewhere, then drill and tap
3 - buy another left side crankcase
4 - other..?
You can't fuck it up anymore than it already is.
I would give JBWeld a whirl before dropping cash on cases. I have built up case flanges with multiple layers of JBWeld, then drill it and tap. Works for me in a few applications, but certainly not all. -BIG DAN:thumb:
 
QUICKSTEEL is another 2 part compound that would be ideal for this problem and at £5 a hit it's awesome stuff and can be drilled and tapped with no mess at all, it even sets grey so ideal for cases!
I have used it for multiple wet or dry applications over the years including on the spot exhaust repairs so will hack a bit of pressure too!

http://www.kalimex.co.uk/our-products/quiksteel
:thumb::thumb::thumb::thumb::thumb:
 
I've got some time for this project now and the first thing that I am thinking about here is that broken piece;
View attachment 30922
What do you guys think is the best option here?
1 - forget about it, run it as is, and wipe off oil after every ride
2 - have it welded somewhere, then drill and tap
3 - buy another left side crankcase
4 - other..?
Weld, re-tap. Problem is it could be warped after if welder is not very good.
But in the heat that you will have by Tuesday, (120*) a magnified glass and a braizing rod you could do it in the driveway.
 
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