its not a 250x its the motor bored out to 350cc, which will out run a 400ex, and then put into a full 250r chassis, so get it through your head! i know that a stock 250x won't even compare to a 250r, but this will.

 

wait one second, this is a quote from www.atving.com "RX conversions dominate the MX and cross-country four-stroke ATV racing scene," see, now do you understand, and wait, this one is by Rocky Ridge Racing. Rockyridge racing is a good place, Brad L, maybe you just got a bad person, i feel that they are very reliable.

 

250xRKrider,

Hey I hope I didn't sound too negative in any of my comments, but I do want you to be happy in whatever you choose to do.

The main reason I commented on this subject is because I am somewhat familiar with it. That article on the RX conversions is dated back around 98 or early 99. I can't remember which. Anyway back then there wasn't such a vast selection of sport quads like there is now.

Before 99 when the 400ex was introduced if someone wanted to build a good four stroke quad they had to go to great lengths. The only things around was the 300ex, warrior, blaster, Banshee, and mojave. All of these could be made to have more power, but none of them handled as good as a 250r. So it only seemed logical at the time to stick a four stroke motor into an R chassis.

I first wanted to build my RX conversion in early 99. The 400ex was still in the spy photo sections of all the magazines at the time. I found an 86 R chassis in which someone TRIED to install a 250x motor. I rode it for 5 minutes and the chain came off and broke the engine case. Honestly, I only rode from my back door to the end of the driveway before this happened.

I knew there had to be a better way. So I found that article on the RX conversions and called up Rocky Ridge, and there rest of that story is up there in the other post.

The conversions still have some good points along with the bad ones. Of course you be the judge on which route you will go.

Some good points are: A little lighter weight due to not having electric start or battery, proven performance (hey its been done before so we know it works), Its an R chassis (need we say more)

Some bad points: difficult to assemble (and if done incorrectly could lead to breaking stuff), old technology in the motor, cost

There are other items in the good and bad points I just brought out a few.

Like I said earlier though, I am not trying to talk you out of doing anything. Although I wouldn't like it if I came here for advice and someone didn't tell me <u>their</u> honest opinion. Then I found out the hard way and thought to myself "Ya'know someone could have told me about this"

 

oh, don't worry about it, i would use a whole 250r if i could find a nice one for sale, at a decent price, yet i think that this might be cheaper to do, if it is done correctly. i like your coments, just not KILLER250R's posts. i am open to any thoughts, because this won't be done for at least a year, hopefully by then i will find a nice complete 250r for sale.

 

Brad L You said it all. There is no way I would try to build up a 250x to get some serios power out of it that would compete with a 250r engine. At the very least I would start with a 350x engine because of the much much larger valves. Or even snag a new 400ex engine from service honda. Back in 1997 I blew the wad (over $2500) to get my 300ex up to the power levels of a 400ex but like you said the reliabilty goes to pot. Maybe if I had a 250x already built and paid for and a 250r chassis laying around I would go for it but otherwise I guarantee you will be disatisfied with the results and all that time and money lost. I am speaking from my personal experience . I have a 300ex pumped up to 406 if you want to give it a try give me a shout , Im parting it out. Its just no comparison to my cannondale speed. Have fun.

 

hey, WISTECH, yes, i already do have a complete 250x lying around. the only reason i was thinking about doing it was because of the money to build up a nice 250r. how much are you selling that 300ex for?

 

please tell me how much, if you are going to part with it, or are you going to sell it for parts?