KTMonda CR500 450sxf conversion

what dose RF4 stand for? how bout an 250 xcf-w. so it will not fit in a ktm "Two Stroke" without a crade swap.
also look at these photos the y for the exhaust on the 250 exc looks like its lower than the 450 but not sure.
in order 2012 450 sxf, 2013 450 sxf,2013 450 exc,2013 350 exc,2013 250 exc

It's the engine model designation for the 07-12 450/505 sxf/xcf engine.

Not w/o bending the cradle to clear in some areas, it's easier to do a complete cradle swap.

Correct

It is lower on the 250.

Like a said before, it will fit in the 450sxf (07-12) the linkage and new frame are irrelevant. all others including the 2013 450sxf will most likely need frame alterations to the cradle.

sorry i did not see its from 07-"12 ". thank you again for all the help. i am now planing on buying a 2011-2012 450 sxf still haven't decided if i should buy it new or used. how much can i sell a new and used 450 sxf engine for do you know?

less than you would think...

If you got $2500 for a new engine you would be doing very well.

The last used motor I saw went for 1100 with a brand new crank and piston, it was a 4 speed though, i'd expect 1500-1800 for a 5 speed.

hey jar hows it going. i have found a EFI kits for the two strokes here it is http://www.ecotrons.com/2_Stroke_Small_Engine_EFI_kit.html
also i have a problem because here in Colombia, SA there arent to many ktm SX for sale most of them are exc. i have been looking at this one http://articulo.tumoto.com.co/MCO-22991325-ktm-ktm-exc-35726-2008-_JM
but here is the hole list of ktms for sale in colombia http://listado.tumoto.com.co/motos/ktm/_OrderId_PRICE do you see any that might work

I would not go EFI. Any of the pre 08 450exc/525exc chassis will work. They are just not as good as the newer models.

why not? pre? do you mean 2008-2011 450exc/525exc chassis will work and that the previos 2007 are not as good as the 2008-2011 models?

i think i found my match it is going to be a 2008-2011 450 EXC here are some pics in order

no the 00-07 chassis will fit the 500 motor it's already been done. the 08+ exc has a larger cradle than any previous chassis.

yea your right the 2008 450 exc has slightly bigger cradle than the 2008 450 sxf
2008 450 EXC 2008 450 SXF

i think i might go for the 2008 450 EXC i now know that the cradel is slightly bigger but i could do longer engine mounts ?

Hey folks. I just had to add in here.

First, jar944, very nice build!!! Good and clean work.

I did a similar thing, but put a KTM engine into a Suzuki frame. It was a 2000 KTM 250 EXC engine and I put it in a 1991 TS 200 frame. I did this when the TS 200 calved on me the second time in one year So instead of dumping all the $$$ into the anemic TS engine, I put in a KTM engine. The nice thing with this build is that the TS is street legal, so now I have a fully street legal KTM two stroke.

Here is a video of the build that I did:

http://www.youtube.com/watch?v=UxFqySg0L6A

Sorry for hijacking the thread, just wanted to add my build in here as well.

Congrats on the successful build. Again, very nice and clean!!!

Incredibly cool project, jar944! I did something fairly similar years back with a KTM 550, but rather than swap frames, I just modernized the suspension, body work, and just about everything else. That 550 mill was a beast. I really wish I hadn't parted with that bike now, but such is life. I'm having fun living vicariously through your thread!

Here's a pic of my old girl (let me know if you want me to remove the photo if you find it disruptive).



Thanks for the great read!

No need to remove it, the plastic conversion looks fantastic.

Thanks for the kind words! The plastic conversion certainly made it look modern, but it was the CRF front fork conversion, the custom Ohlins shock, and the balancing, polishing, and porting (my builder estimated 75 hp - I have no idea, but it was too fast for me!) that made it a blast to ride!

Keep up the good work, your bike looks amazing!

Cherokee?

nice, I didn't notice the Showas.

edit I knew I'd seen your bike before https://www.youtube.com/watch?v=YharXbUkMZo

you had a build thread in the olde section on KTMtalk correct?

Ha ha, it's been a LONG time since I heard that name, but yes, that's correct! Do you know Cherokee? What a great guy....

I used to frequent the KTMtalk site quite a bit, and yes, I did a build thread on the bike over there under the same screen name, but unfortunately I later changed something in my Photobucket account and all of the pictures got moved, so the links no longer work.

Did you or do you frequent that site? I miss the site and the bike. Like I said, stupid decision to sell it.

Again, awesome project and it looks like your skills are well above and beyond mine (not too tough). Enjoy riding that beast!

Didn't the article say that guy used a KTM 125 2T for his conversion? From looking over your posts (thanks JAR944 for all the great pics and info, BTW), it looks like you recommend only 07/08 450/505 SXF/XCF frames and think any other frame would require a cradle swap modification, correct? I'd like to do one of these myself, but reconfiguring an engine cradle is above my head. If I go for it, I want to make sure I start with a frame that requires minimum modification (ideally only removing and rewelding the engine mounts).

Aaron C.

I reread that Dirt Rider article, he used a 2010 250SX 2T for the chassis. They didn't get into to details on building it but said it "was surprisingly easy".

i have the article. It's not a 2t frame, or at the very minimum they used a 250sxf cradle. Likely though it's a full 250sxf frame which is a good bit harder to make work than a 450sxf frame. Also its a mix of years/parts. The wheels/hubs/rotors are 05-06

Well, just took another look at the article and they mention twice the frame being from a 2012 250 SX, but you have the experience here. I'll keep my eye out for a 450SX/XC chassis to keep it simple, thanks again!