KTMonda CR500 450sxf conversion

Looks great.. Wow..

I'm jealous.

Just some pics of the cdi placement, coolant block off for the head, and carb fitment.

Shhhhh!

Do you hear that?

That motor is beggining for a new flat slide carb and some V Force Reeds!

Ha that's a 39.5mm PWK in the pic. If it gets anything it will be a rad valve so I can change the carb angle to match the air boot perfectly.

Is that one panel with the slight blue tint an Acerbis?

I ended up going with all UFO plastics on my '09 KTM, for that bright white color.

Can't wait for a ride report!!!! Beautiful work

The side panel / airbox is OEM

I wasnt happy with the exhaust mounting and routing so i decided to fix it

tweaked silencer



way more clearance


rear pipe mount


The pipe is cut back to the cone and the flange and rear mount welded



exhaust complete


compelted head stays


It's Done. the only custom parts are the frame mounts, head stay and the exhaust and even that isn't much work

also with this conversion I can pull the carb with everything in place (unlike the AF's)

NICE job. My CR500AF is still my favorite bike to ride. ENJOY!

RIDE ON!

I got the magura installed.. much better. now to get the decomp done.

I took it for it's first real ride finally today. about 30 miles of rock infested trail.

Firstly, the suspension is not even close for rocks, but i knew that going in to today I just slapped a spare 08 250sxf shock and stock 450sxf front end.

Happily even with the susp it wasn't bad in the rocks, I ended up feeling better after that run than I have on any of my other bikes.

On to the handling. It doesn't any lighter pushing it around the garage or lifting it than my RFS hybrids or 450sxf (and it shouldn't since it weighs as much) however when moving it feels lighter and more flickable.

Power wise.. what can i say it's a 500cc 2t. People fear them, honestly though after spending some time on it I have no idea why? It's a smooth power that IMHO is very easy to ride. It has instant off idle Tq, way more than my TR570 w/ a 806 cam (and i thought that was torquey) that builds quickly and signs off early. It feels strange revving it out but on the plus side you don't need to if you don't want. Vibration is noticeable above 1/2 throttle, not horrible though.

I found myself going too fast into some corners w/o realizing how much speed I was carrying, it's deceptive speed. Burp the throttle and you move faster and faster.

All in all once I sort out the suspension I think this may be my favorite new bike. sure it has down sides but overall i think the KTMCR5 is a good combo.

Great build!

Could you please post a little video showing how the bike does?

It seems to be a really nice and powerful combo the one you've made...

I think that maybe people is scared of the 500cc 2t because they don't know how to control all that power in the throttle...
For me it's all a question of practise and confidence in the bike, and also a lot of respect to it..

That's all for now
Thanks for showing it to us!
Greetings from Argentina!

Jar944 - I always love your build threads as they do a lot of what I wish i had the skills to take on. Congrats on putting together some fun projects

Very interesting to hear that there was not that much real weight savings with this project over the RFS. I always complain about my 4 strokes seeming a lot heavier than the two strokes I used to race. +1 on the CR500's not being scary but just huge torque monsters. I'm a girly 140 pounds and raced one in an enduro twice and it was so torquey it was like cheating. For 3/4 of the race i thought it was all peaches and cream, not until I got tired in the last 1/4 of the race did the cr500 become too much.

Can I ask how much of a real world improvement you found in your RFS hybrid projects in terms of handling? Did it flick side to side (like threading it fast through 1st and 2nd gear tree's) any better? What were the key benefits you found to doing that upgrade? I've got a 2010 set of forks to bolt on the RFS if I want and wondering if the frame contributes that much additional benefit to the overall package? Or maybe the later model suspension is the key component providing the benefits.

I'm asking as I've got a TR570 like you and wondering if its worth the bother to do it or just take it in the ass buying a 2nd hand 500exc in a year if all the FI problems can be dealt with enough for me to ride it on long multi week rides in a third world country like my RFS does.

Again great job on the build!!

Justin

Justin, Thanks for the compliments on the builds. I've always enjoyed the fabrication side as much as riding. Since I moved out of the country and into the suburbs I have a lot less riding opportunities, so i spend more time in the garage building.

Regarding the RFS hybrids, no they are not any more flickable than a std RFS. I think that flickability has to do with the motor placement and gyroscopic effect of the engine. Neither of those change on the hybrid. The area that really improved was the turning & handling of the chassis. It goes exactly where you point it, never washes out and generally inspires more confidence for me than the RFS ever did. The suspension action is considerably better than anything on a rfs, but most of that is likely the improved forks and shock.

I was thinking of a 500 myself, but like you the FI issues and lack of ability to unlock the ecu made me change my mind.

-Jared

Jared - Thank you for the feedback on the projects. Great to see you squeaking the most out of bike ownership getting not only the joy of riding but also fabbing up the special rides.

What made you want to stuff the CR500 mill into a KTM chassis as opposed to a CRF 250?

I had a spare KTM roller just sitting in my garage when I saw a thread on a ktm/honda conversion. I just happened to check craigslist a few days later and there was a cr500 posted for $500.

I liked how the chassis handled and since that I already had a few KTMs with the same chassis it made the decision easy. With multiple bikes it's nice when they all share parts.

2nd real outing

http://www.youtube.com/watch?v=ks4VM4OaWes&feature=youtu.be

Pulled the head to cut the squish and add a decomp. Unfortunately it's too big to fit in my 4 jaw. Looks like I need to make a fixture to hold it

Looks a little rich (only about 4 hours on the motor)

I drilled and tapped the head (8x1.25) for a decomp. The valve was 10x1.0 and I thought could get away re-threading for use w/o a adapter. Needless to say I was in a hurry and didn't think it through. I'll be turning an adapter when the new decomp arrives.

Great build! What year cr500 motor did you use? And can you provide detail on the magura clutch?

-Scott

thanks. The motor is a 91.

What would you like to know about the clutch? I'd have to check the box but I believe it's for a 07 crf250r

Thanks for sharing. I think. See stuff like this makes me hate father time even more.............