250r engine in a 400ex frame

[LazeR]

I know this has been asked before but what exactly is needed to put a 250r engine in a 400ex ? I found a 250r 3-wheeler for $250 in the paper, and it will be mine depending on how it looks if i can get ahold of the guy, and i would want to put it in my 400ex! Is there a kit that you can buy to put it in the 400ex or does it all have to be fabbed ?

[hondardr4life]

www.servicehonda.com I am pretty sure that they sell a kit.

[deathman53]

$250 a 250r trike? seams a bit too good to be true, post some pics of it when you get it. I have one and possibly would be interested in some of the parts, ex: swinger, forks, frame, foot pegs. Make sure its a liquid cooled motor, the aircoolers won't work. If you don't pick it up, post some pics and I'm pretty sure that I know of some poeple in your area that would be interested in it.

well heres where your gonna have problems.. if its a water pumper R then it would work, but if its not, it wont due to the right side drive of the air cooled r as oppsed to the left side drive of the water pumper

Jesse

[LazeR]

thanx for the heads up guys! Haven't gotten ahold of the guy yet, so we will see


I know service honda has their kit, but that is the motor, frame, airbox and whatnot.....i just want a kit for the engine mounts pretty much ;)

[hondardr4life]

Originally posted by LazeR
I know service honda has their kit, but that is the motor, frame, airbox and whatnot.....i just want a kit for the engine mounts pretty much ;)

I thought they had a kit with motor mounts. :confused:

[LazeR]

Originally posted by hondardr4life
I thought they had a kit with motor mounts. :confused:

When i get home from school i will look harder!


If anyone has anything to add please do!

[deathman53]

the service honda kit is for a cr250r motor, not a atc/atv 250r motor

[LazeR]

Meh its not gonna work anyway :( They sold the 3 wheeler, but it was air cooled so it wouldnt of worked anyway!

Wonder how much the kit is and a cr250r motor is :ermm:

[deathman53]

its almost 4g's. You'd be better off buying a 25or motor and radiator from ebay, or a local shop. East coast Atv has them for sale,

http://www.eastcoastatv.com/motors.htm

[grabberblue]

Here's a firsthand account of the swap. Over the last couple nights ive been workin on it The first critical factor in the mounts are the relationship of the front spocket and the swingarm pivot. This also effects the alignment of the drive chain.
you can use a 86-87 trx 250r rear motor mount with a .100 thick washer on each side ( I welded them cause they kept fallin out with all the trial fits) You need to use two short side 400ex swingarm pivot sleeves. This will put the front sprocket in postion.
Next you will find that two right side 400ex frt mounts will will work up front with some file work and a .300 spacer on the leftside. The top mount can be made with the 400 top bolt and ears welded to the bottom of upper frame rail. The spacers will have to be made to fit depending on your mount. The last mount will have to be made from scratch,i used a peice of flat steel across the top of the lower framerails and made ears to go to the bottom bolt.

The next issue is the carb its really a tight fit you cannot use any reed spacer,and the stock rubber intake needs to be heated and the carb pulled down in back to clear the frame .

The rear shock needs to be reversed so the resevoir is in the back. This makes the 400 air box no good, but it feeds over the frame and the "r" carb is under the frame.



Thats all I could do till ups brings my pipe and 250r air box . I will post another update soon

[LazeR]

Originally posted by grabberblue
Here's a firsthand account of the swap. Over the last couple nights ive been workin on it The first critical factor in the mounts are the relationship of the front spocket and the swingarm pivot. This also effects the alignment of the drive chain.
you can use a 86-87 trx 250r rear motor mount with a .100 thick washer on each side ( I welded them cause they kept fallin out with all the trial fits) You need to use two short side 400ex swingarm pivot sleeves. This will put the front sprocket in postion.
Next you will find that two right side 400ex frt mounts will will work up front with some file work and a .300 spacer on the leftside. The top mount can be made with the 400 top bolt and ears welded to the bottom of upper frame rail. The spacers will have to be made to fit depending on your mount. The last mount will have to be made from scratch,i used a peice of flat steel across the top of the lower framerails and made ears to go to the bottom bolt.

The next issue is the carb its really a tight fit you cannot use any reed spacer,and the stock rubber intake needs to be heated and the carb pulled down in back to clear the frame .

The rear shock needs to be reversed so the resevoir is in the back. This makes the 400 air box no good, but it feeds over the frame and the "r" carb is under the frame.



Thats all I could do till ups brings my pipe and 250r air box . I will post another update soon

So far doesnt sound to terribly hard! Please update when you get more, id like to know what it takes, im seriously considering this

What about mounts for the radiator ?

Thanx

[grabberblue]

Swap update; Started the exhaust with stock trx 250r pipe. It was no good cause it hit frame so i cut and welded the hell out of it and mated it to a stock silencer. I am not happy with this set-up so i will be looking at a couple of aftermarket pipes that pass thru the frame to give more room for radiator.
The frame tubes that hold the fender supports interfere with the radiator so i reshaped them to run straight down below the fender mounts.

[grabberblue]

I just got the exhaust finished, i used a old bills pipe for a trx. I shortened the header pipe 2.0" to clear the steering,and made a small dent to clear a bolt by the kicstarter. The stock trx radiator now fits great but i have to have the bottom outlet moved in 2" You may be able to clear that outlet with different pipe. For the intake i ordered a ESR air box eliminater kit. If the filter get to much crud on it i will make a airbox
For the silencer i used a stock trx but i made the brackets and tweeked the inlet to match the pipe being 2" farther back.
Everything else is looking great , i will have pictures soon.

[2muchquad]

let me know how that runs,man 2inches off the headpipe,your gonna lose what lil' lowend your 250 had.it may be more of a "big" 125 now.a lot of people dont run the DG 250r pipes,it will probably fit better.but they have awesome torque for play riding.they just dont come in fancy chrome plating,i bought mine off ebay for $12.im gonna start my cr250 motor in 400ex chassis soon,i may us it.