300ex/250x kick conversion

[drip]

My friend recently purchased a 300ex and has a 250x for parts. He was wondering if it is possible to put the kick starter from the 250x on the 300ex? He doesn't want to tear the 300ex apart to find out if it will work or not. If anyone knows anything about this from experience I would appreciate a response. I don't want any responses of what someone has heard. I want replies from people who have actually tried this or from people who actually know someone that has done this. If you know someone that has done this I would like to ask them a few questions.

[wyotrey]

id like to know that as well. it could really cut down on some weight....:confused:

[killer03_300ex]

ive been thinking about that to im pretty sure you can do it its just how

[300EXrider02]

nope it is not possible, I remember a thread back in the day, and there were just too damn many things to have work to make it happen, too much trouble for nothing

[Chanman420q]

i think it would, ive heard someone talkin about having a kick start 400ex..... side case from the XR400

[MXQUAD294]

Give TC Racing a call. I know he did it back in '98 when he built the first Pro 400cc four stroke. He used a 300EX motor but put the 250X kicker in it. Here's part from a story from the Aug. '98 issue of 4-wheel/ATV Action.

[300EXrider02]

yup, it takes shaving and a lot of time, very hard for an average joe to do

[ZRider400]

couldnt you use a 250x clutch cover on it? instead of machining the 300ex one.

[HotRod2Fitty]

All you have to do is get all of the kickstart parts and just use the sidecase off the 250x.

[phatswinn]

or if ur really ghetto you could rig something up to the gear the electric motor uses

[bigbadbrad]

why dont he just use the 250x botom end, and the 300ex topend, with an higher comp. piston?

[ACracin300ex]

WEll, the electrics on my 300ex suck, and i also have a flat spot in my starter. What if i purchased a 250x bottom end. Would all the 300ex top end parts fit on the bottom end? i am running the powroll 329 kit, so im wondering if the 250x bottom end will hold up to more power?

[racinred330ex]

a 300ex is a bored 250x the top end should bolt right up

[drip]

Thanks for the responses. My friend and I are going to tear into it after he goes back work. Right now he is on vacation and he is riding the 300EX all the time. I'll let you know how it goes and maybe take some pics.

[TRX300X]

A 300EX is a stroked 250X the bores are the same and everything in the top end are interchangeable minus the pistons because of the different wrist pin location. What would be a hot set up would be to use the EX craank in the X engine and you could have a 330 kickstart 250X.

As far as using the X clutch cover on the EX engine do not do it. Some of the electrical for the reverse switch is different as well as some of the oil passages in the side cover. You need to retain your stock cover and machine it.

[ZRider400]

On the 250x there is a decompression.......on the 300ex there isnt..... i noticed this wh en i was going to put a 300ex rocker cover on my 250x. But ended up not doing it. Would that really affect it not having a decompression release?..wouldnt it be really hard to kick.

[nismo]

i took the decompression off my 250x and its a little hard to kick but being my size(skinny) i deal

[ACracin300ex]

well i have the 329 kit from powroll....so could i use the 250x bottom end, and the 300ex cylinder, piston, valves, and rockercovers?

[honda250xrider]

no its still not hard to kick over without the decompressor on. I can still kick it over sitting down on the quad.

[Rastus]

It's not really that hard to kick over. It just takes some getting used to.


Also, the conversion can be done, but you'd have to drill then get precise measurements. You'd also have to have the seals to go around the kicker, and all that BS.

[250x#93]

I like the kick:cool:

[drip]

Originally posted by TRX300X
As far as using the X clutch cover on the EX engine do not do it. Some of the electrical for the reverse switch is different as well as some of the oil passages in the side cover. You need to retain your stock cover and machine it.
Have you actually tried this? Have you had both covers in front of you to compare? Or is this what you have heard? I want to hear from someone who has actually tried this conversion.

[TRX_Thumper]

in a previous post someone showed some info on what TC racing said about it...well dont you think he would have bought a 250x sidecase instead of machining the 300ex one if it was possible?

[drip]

Not when a new one costs $190. Plus TRX300X doesn't own a 300ex, he owns a modded 250x.

[TRX_Thumper]

well if you want to try it out i have two 250x sidecases to anyone $35 shipped apiece

[drip]

My friend just flipped his 300ex yesterday so I think we will be starting this project soon since his quad is down for a few days.

[TRX300X]

Buy a manual, or look up the parts breakdown there's more difference to the covers then just the kickstart and the decompression. I do motorcycle/ATV repair from my home on the side and I've had enough of them apart to tell you this.