KX500 swap into 1985 LT250

[Burle]

I did this project a couple years ago but just got around to finding all the pictures and doing this write up. Got my hands on a KX500 engine and thought I'd try putting it in a quad. I found a rolling chassis, a 1985 Suzuki LT250, the frame had a gusset kit installed, the A arms are 2" forward and 3" wider (6" total), swingarm is an 8" extended swingarm and the axle is 8" wider than stock. Front suspension are shocks from a YZ and the rear suspension is Elka.


The engine went straight into the swingarm mount, the swingarm bolt was same diameter as the KX500 bolt. Didn't have to do anything to make that mount work. Then just had to fab up the other mounts

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[Burle]

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I had a head that somebody had chopped short, I think to try and do an AF conversion. I welded on an aluminum rod

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[Burle]

The pipe was a real pain, I used a stock KX500 pipe and chopped it and then rotated the pieces and welded them back together

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[Burle]

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[Sandblaster]

Wow!
Very nice work.
Looks like the kick lever has no clearance issues.
Have you finished it enough to ride it?
If so, what did you do to the engine?

[Burle]

Internet was giving me some grief last night so I didn't finish this. The kick lever worked perfectly just like the swingarm engine mount, rear brake lever also fit perfect, the shift lever was a bit too far back so I got one of those levers that's extended 20mm (I think).

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When I was doing research for this everybody said putting a big bore 2t in a quad chassis will increase the vibes tenfold (something to do with the fact it's on 4 wheel instead of 2). I was looking at ways to rubber mount the engine and/or install a counter balancer, but just decided to go ahead with it and then do that after if it really needed it. I've never had a problem with the vibes on any 500 and it's the same with the quad, I don't know what guys are talking about.

The engine is fairly stock, no porting or compression work, wiseco piston, hot rods con rod , LA sleeved cylinder, and a MZB ignition (cause I had one laying around). I took it down to the Idaho dunes, did really good, I was able to out accelerate my brother (same body weight as me) on his 97 KX250. Really surprised me. I weighed it by putting a bathroom scale under each tire and adding up the weights and it weighs 399lbs. Not very precise but in the neighborhood.

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[Burle]

After that trip to Idaho I added a bracket on the back for an extra 10L gas can, the thing is a thirsty pig in the sand and I couldn't go very far from camp. I haven't rode it since adding the bracket, if this Rona border closure ends before winter I really want to go back to idaho

[Burle]

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[Sandblaster]

I see a snow bike

[Sandblaster]

There have been a lot of positive comments on Facebook regarding this build.
The only negative thing posted was a guy who said that these frames are pretty light and prone to crack.
That's ok, you find the weakness and make it better than it was before