KX Riders

Maintenance & Technical => KX500 Steel Frame Conversion (SFC) => Topic started by: chilihoop on September 20, 2014, 06:27:25 PM

Title: ktm kx conversion
Post by: chilihoop on September 20, 2014, 06:27:25 PM
Trying my hand at a 2008 KTM sxf 450 to KX 500 conversion and I have a question about what air box I should be using. The four stroke ktm boot is much higher than the kx 500 carb. Any suggestions would be greatly appreciated.
Title: Re: ktm kx conversion
Post by: cmotodad on September 21, 2014, 07:41:12 AM
Thought I read a 2000 CR250 boot was used on one. What about the KTM 250sx boot?If that was close, that would be my choice
Title: Re: ktm kx conversion
Post by: Kracer on October 14, 2014, 11:34:11 PM
Chilihoop,
  I did an 2006 Ktm/Kx500 conversion.  On my conversion I used the stock 450/525 airbox, and bought a Ktm 250sx airboot.  The airboot mated up perfectly to the KX-500 engine.  --Kracer
Title: Re: ktm kx conversion
Post by: chilihoop on October 28, 2014, 04:21:46 PM
Thanks for that Kracer. Did you have to put a 6mm spacer on the right side of the swingarm pivot to align the countershaft and swingarm, read that somewhere. What about the engine mounting brackets---when I installed the spacer on the swingarm bolt it moves the whole motor to the left, which puts it slightly off centre. Any information would be greatly appreciated.
Title: Re: ktm kx conversion
Post by: Kracer on October 31, 2014, 02:27:42 AM
Chilihoop,  The way I did it, (and there might be a much better way).  Was yes, I put in the motor (with a brand new countershaft sprocket on), put in the swingarm, with the rear tire, a brand new rear sprocket mounted, of course measured from the swingarm pivot, to the rear axle centerlines on both sides, with the rear axle as far to the rear as I could get it.  I used a straight edge, and a fine piece of thread, that I could see really well, and made sure that the center line of both sprockets lined up perfectly.  I was VERY meticulous about this.  I made the left side spacer first, (the side with the countershaft).  I did a lot of hand filing on both spacers, to get this exact.  To be honest, I don't remember the measurements of the spacers.  To me, this is procedure is something that I always do, I had a couple of Service Honda's made for me a few years ago, and you wouldn't believe how far off their spacers were.  (The chain kept de-railing on one of them, and I had to totally re-work the bike!)  That's when I decided to build my own conversion.  If you want Chilihoop, I can get the measurements for you, but you should really handfit those spacers, and be meticulous.  Nothing worse than having your bike tapped-out, bottoming your suspension, and having your chain de-rail.  Especially if you are an old fat guy, like me--Kracer
Title: Re: ktm kx conversion
Post by: crusher on December 06, 2014, 03:42:54 PM
Hey just wondering where you guys are getting your pipes for the conversion....
Title: Re: ktm kx conversion
Post by: vagassasson on December 20, 2014, 12:23:38 PM
Hey just wondering where you guys are getting your pipes for the conversion....
I think a lot of guys are using the ktm 300 2 stroke pipe
And some are having custom pipes made
Title: Re: ktm kx conversion
Post by: alward25 on December 20, 2014, 12:46:36 PM
I would not expect the KTM 300 exhaust to be big enough to let the K5 breathe right unless you are only doing lower rpm trail stuff.  I will be doing a CPI on mine based on what I have seen on IDKX500's Christini project.
Title: Re: ktm kx conversion
Post by: ID KX500 on December 20, 2014, 04:42:15 PM
Trying my hand at a 2008 KTM sxf 450 to KX 500 conversion and I have a question about what air box I should be using. The four stroke ktm boot is much higher than the kx 500 carb. Any suggestions would be greatly appreciated.
I used the boot for a the 300, it fits on the air box you have.