trx250r motor in a400ex frame?

[jhtrx250r]

I have seen a few in the past, Now I want to build my own!

any one have any info on the conversion?
any pics of your own?
any one make a conversion kit?
I have seen old service honda srx250r pics (400ex frame with cr250 motor service honda kit)
any and all info would help, I have 2 400ex frames a 2000 & 2002
and all the suspension parts I need.
310 pv motor and a 250r stocker

Thanks for all your help

[GOTFEAR]

Why? if you do this it stile wont run with a r ........

[jhtrx250r]

reason would be, I have a few R's,
I like the fell of the 400ex chassie also there are a lot more chassie performance parts avalible for a 400ex at this time then for the R
also the geometry of the stock 400ex frame is similar to that of a good aftermarket chassie Lonestar ect.
(the 400ex chassie was hondas first attempt at a performance Quad after the legenary R)
The stock square tube frame of the R can be proned to cracking.
I have a very nice 86 and a 88 spred out all over my shop
I plan on puting my PV "R" motor in the 400ex frame.
It is twice as fast as the heavy klunky 400ex motor that came out of the chassie, and faster than most of the other R's I have encountered.
I feel this would be a good mix of power and rider comfort

[mg82]

i too am wanting to do this conversion. let me know if you make any headway. surely somebody has some insight....

[Langbolt]

jhtrx250r:

If you're planning on using the TRX250R motor the main problem is the carb.

I'll post some pics ( I have them backed up on cd's at home)

I tried this and the angle from the intake manifold to the carb puts the carb right in the path of the 400ex frame cross support.

I have pics showing this support being cut & replaced.

I don't know if you'll want to go to that extreme.....but once you see the pics you'll know what I mean.

[Langbolt]

Ok .....Here's a pic with the TRX250R motor in the 400EX frame.

[Langbolt]

Sorry....the pic with the frame cut is a CRF450 motor in a 400EX frame.

[Langbolt]

Here's the frame....modified for the CRF450R motor

[scottsworld]

any finished pics

[Langbolt]

Nope.....:(

The 250R in a 400EX was a project that a bunch of friends all got to gether with spare parts and what you see in the picture is what we had.....just to see if it could be done. I bought a 400ex frame and started working on it......but scrapped the idea when I realized what I got myself into & also got myself involved in my 600cc hybrid (XL600 motor in a 400ex - which came out great!)

The CRF450R pics were snagged from a different site.

:D

[michaelopfer]

I don't know how to post pics but I did the conversion and it's reletivly easy, but the exhaust (trx 5 ) is just a little too long, and hits the tierods if its not a little bit crooked. the carb barely fit under the rail but it fit fine,
anything else let me knowt

[michaelopfer]

langbolt, what exhaust do you have mounted in the pic? does it fit, and yet clear the tie rods??

I do have pics of finished product if someone wants to post them for me..

[Langbolt]

Unfortunately the pipe was fit loosley....not mounted.

Here's a link to a finished 250R in a 400ex chassis.

http://www.exriders.com/vbb/showthread.php?s=&threadid=336762

:devil: