ktm 450xc motor in a stock trx 250r frame

[jboz5786]

I was wondering if its been done before. How hard would it be you think to do it. Thanks

[jcs003]

doesn't KTM make a quad with the 525 motor in it???

[jboz5786]

Yes they do. But i already own a ktm and Im wanting to put a ktm 450 xc motor in a trx 250r frame...... Not a 525..... See where Im going with this?

[protraxrptr17]

It's pretty tough if you do it right. Some just stick it in there in front of the swingarm. You can look up my post about the YFZ/525 I'm doing and you'll see kinda what has to be done. It should be on page two of this section.

[jboz5786]

Ok thanks

[jboz5786]

Yeah it looked tough to do but it looks good in there. I see you own a metal fab shop that must help out allot. Im trying to open one up where I live so I can do this kinda work. I love doing it.

[250Renvy]

Seriously, Can a mod make a sticky or something - it seems every other post is : .... big tall fourstroke motor into a stock 250R frame.

It's the same fricken answer everytime people.

The fourstroke motors are TOO TALL for the 250R frame. The frame needs to be cut and the frame rails lowered.

There is a lot of fab work involved but most times the frame doesn't hold up because they are 20+ years old and the person doesn't know how to keep the stress away from both the welds or an unforseen area and it cracks repeatedly

Plus it doesn't make sense when there is a plethora of four-stroke atv's built from the factory that everything fits and is nice and it doesn't ruin yet ANOTHER good 250R frame - and if you are starting with a junk 250r frame or one that has been converted to something before, there is an even greater chance of it being more junk after since the original strength has been compromised.

There are plenty of Hybrid 250R frames out there - not that I advocate cutting them up, but it makes more sense since the lower frame rails are lower and made for a bigger motor in addition to the chromoly being much stonger than the mild steel frame.

Torque from the motor is often a problem as well, if the motor isn't braced properly it causes the frame to twist.

Oh and everybody asks if it's been done before and the answer is yes, it's just not that common.

Here's a small list of motors I've seen done (whether successfully or not into 250R frames)
Yamaha YZ426F - YZ450F
Yamaha Banshee
Yamaha Blaster
Yamaha YZ250
Honda CRF450
Honda CR80
Honda CR500
Honda CR250F
Honda CR125
Honda 300ex
Honda 350X
KTM 525
KTM 300
Honda CBR600
Suzuki LTZ400
Kawasaki Mojave
Kawasaki KX500

Probably a ton more that I haven't mentioned


Sorry for the rant, it's just necessary.

[jboz5786]

WOW why's this guy all butt hurt about me wanting to see what I can create? Its non of your concert so stay out of my post if your going to trash talk. Don't b*itch about something someone else wants to do. You have a hybrid anyways so why are you complaining about something that you have already done??????

[jboz5786]

Im hear like you and every other person on this site is here for I want to ride and I want to customize DON'T HATE!!!!!

[250Renvy]

It's not about what you want to create, its the question you asked. Did you read my post? Did you do a search? There are plenty of threads asking the same thing with the same answers.

BTW, my hybrids are build that way and are not stock frames that are hacked up. BIG difference.

It's not about hating, it's about come on really?

If you were new, it wouldn't be a big deal, but even when I was new I didn't ask - hey guys what do you think about putting a fourstroke bike motor into a 250R frame. And if you are asking about an ATV motor, then I'm not sure where you'd find one and what the point of that would be since the KTM quad is better than a stock 250r.

[jboz5786]

well apparently you didn't read my post either. I already have a ktm quad I have a extra motor that collecting dust and a 250r that doing the same thing. And no this isn't my first rodeo . I know what Im talking about so you should just leave it at that ok? I was asking if anyone has done this before? Im getting ideas? Is that ok ? Or should I consult you every time I have a thought in my head? Look you can't tell me or anyone else what to do you don't have the power so if Im going to build what I want then Im going to build what I want just to prove to people like you it can be done. Oh and by the way not all motors and quads are the same if they where this site would be a waste of time.

[jcs003]

Originally posted by jboz5786
Yes they do. But i already own a ktm and Im wanting to put a ktm 450 xc motor in a trx 250r frame...... Not a 525..... See where Im going with this?

i understand. a friend got an crf450r at an auction for $200 and built a hybrid last year and people challenged him. sorry if i was being irrational.

[jboz5786]

Its cool. Im not upset about any of this. Words don't hurt they just add fuel to my fire. If Im going to do something no one can stand in the way. I don't care if this ideas has been done a million times if I want to do I will and if anyone has a problem with it then theirs the door you don't have to know or even hear about it. Thats just how I feel. Im sorry if I sound like a prick but I don't hold nothing back when someone has to tell me diffrent.

[250Renvy]

Originally posted by 250Renvy

The fourstroke motors are TOO TALL for the 250R frame. The frame needs to be cut and the frame rails lowered.

There is a lot of fab work involved but most times the frame doesn't hold up because they are 20+ years old and the person doesn't know how to keep the stress away from both the welds or an unforseen area and it cracks repeatedly

Sorry for the rant, it's just necessary.


I didn't say you couldn't do it, and as if I could stop you. See this part where I tell you what needs to be done ^^^^

And I also told you there are much better options than a stock 250R frame.

And what is there to prove? I know it can be done, it's been posted on here a bunch of times - search function

see : http://www.exriders.com/vbb/showthread.php?s=&threadid=325935

http://www.exriders.com/vbb/showthread.php?s=&threadid=372231

Also, if you have spare 450XC motor and a spare 250R, why not sell them and buy a hybrid, you'd probably get good $ for the motor and 250R.

[vAnS_77]

If you want to get a hybrid frame, just get a 400ex and get a company to make motor mounts and extend the frame. I think JB racing might still be fabbing up some frames for you if you pay enough. I have seen angle iron used for a crf into a 250r...It's just plain stupid. I agree with envy....don't hack a good oldie frame up for a motor that can fit into a 400ex chassis perfectly fine!

[jboz5786]

I can do all my fab work I have my own shop that what I do for a side job. Im not a fan of the 400ex frames. Ill just use the r frame. It was made for a reason to be ridden on and I paid my hard earned money on it so its up to me to build what I want with it. Why doesn't anyone get it? Why do guys build hopped up full blown drag racing mustang's instead of restoring them? Because they don't want too!!! People have a image in there minds and they go with it. Its called not be a ordinary. Its living a little! How many r's do you see with KTM motors in them?.....Not allot thats why Im going to build one. END OF STORY!!!!!!!!!!!!!!!!!!!!

[vAnS_77]

Originally posted by jboz5786
I can do all my fab work I have my own shop that what I do for a side job. Im not a fan of the 400ex frames. Ill just use the r frame. It was made for a reason to be ridden on and I paid my hard earned money on it so its up to me to build what I want with it. Why doesn't anyone get it? Why do guys build hopped up full blown drag racing mustang's instead of restoring them? Because they don't want too!!! People have a image in there minds and they go with it. Its called not be a ordinary. Its living a little! How many r's do you see with KTM motors in them?.....Not allot thats why Im going to build one. END OF STORY!!!!!!!!!!!!!!!!!!!!

We aren't trying to hurt your feelings at all. It's the fact that we don't want to do all that work then get down talked about it because it doesn't look like the other guys ktm in a frame that didn't need to be hacked up. All we are trying to say is, if you are going to do it. Commit to it and do it the right way. I've have seen PLENTY of hybrids that are the most ugliest quads in the whole world. If you are going to do it, and you want to be known for doing it. Do a nice job! That's all we are trying to say!

[protraxrptr17]

I heard some of the same stuff when I put the 525 in mine. They said it was too hard, it was a waste because it was a Raptor, it wouldn't hold up. They all make a good point though, because if you DO hack it up, it will be a waste of time and money. But I believe anything is worth doing if you want to do it right. I'm sure somebody once told Mike Walsh to go buy a frame instead of building his own. There is something to be said for doing something yourself, IF and only if you are willing to take the time to do it right.

I understand not wanting to have the same old storebought bike as everybody else. I could have probably 3 rigged out storebought ones for the time I have spent making custom parts for mine, but then it would just be like everybody elses. I raced at Oak Hill in '07 and a golf cart pulled into my pits behind me after my first moto. There were three guys in it who noticed my bike and wanted to check it out. Pat Brown, Rocco Arno and Dustin Wimmer. If I was riding a 450R like everyboy else, nobody would have noticed.

[protraxrptr17]

Oh, and by the way, I built most of my bike before I had a real shop. I built it in a 8 X 10 plastic building I bought at Lowes. I had a nice welder but I used just your basic drill, grinder, files, and stuff that everybody has. I talked a local race car shop into bending a piece of tubing for me.

[jboz5786]

Im not out doing a hack job believe me If Im thinking about my life and other riders lives when I race I don't want to do a half *ss job . I don't have the nice tig welders or a cnc machine or plasma cutter but I do have the 8 years metal fab work to back my jobs up with. Im good at what I do. Yes thats what Im trying to get at to other people I don't want a quad that over 4000 people have already. I want to be diffrent.

[woodsracer144]

if you have another KTM 450XC motor and a another 250r chassis i would sell the 250r chassis to some one who will use it how it should be used... with a 250r motor and buy another ktm chassis or a different chassis that is ment for a taller motor, i thought about doing swaps in a old 250r chassis i had but it wasnt worth it...

or heres another idea... sell both of them! motor and chassis and use the money on your quad...

i am gonna be backin 250Renvy... search his name... and check out his build on the has going with his custom chassis...

[C41Xracer]

woodsracer, i dont think anyone is going to change his mind. Good luck on your build.......have you even started it yet?if so where are the pics????

[coryatver]

Sure you can do it but man you better be a good fabricator and have money to burn

[C41Xracer]

Originally posted by coryatver
Sure you can do it but man you better be a good fabricator and have money to burn

money to burn??why do you say that. my hybrid wasnt that expensive

[vAnS_77]

Originally posted by C41Xracer
money to burn??why do you say that. my hybrid wasnt that expensive

My build cost 10 grand...For everything aftermarket...everything..lol

[C41Xracer]

if you buy everything new then yeah it can get expensive....if you can get parts used then its not bad. my crf quad cost me 10k plus. this yz quad is only gonna be around 5500

[jboz5786]

Im a good fabricator Ive gone to welding school opening up my own shop soon. i work on drag racing chassis and late model and IMCA modified dirt track car chassis. Im not worried about the money. No I haven't started yet Im needing to finish up my lt 250r then ill start the trx ktm project. Ill finish the lt up and begin on the big project. Ive already wrote down a plan of attack on this project.

[jboz5786]

Im only found one problem me and a fellow fabricator might have the problem solved though. This should go pretty smoothly. Im going to take my time and not rush. I believe Ill have a really powerful quad with the good old R handling that I like:D

[trex450]

just get a 400ex and get a company to make motor mounts and extend the frame. I think JB racing might still be fabbing up some frames for you if you pay enough.