I also have a 250x and am looking into that conversion.

 

I also have a 250x and am looking into that conversion.

 

I think '85 and 86' are the same in the HP/speed dept.

To Hang with a 400EX, a 350X needs 4 wheels. Thats about it. Except if you make it a 4wheeler, that adds weight, then I don't think it would keep up to the EX. Unless the motor was bored out or made even stronger. My 400EX walks away from my 350X in any condtions other than a straight flat line. Of course my 350X is what, 15 years old? In a straight line on the road, they are about the same speed, the 400EX creeps ahead when wound out in fifth. In a short dragrace, I think the 350 would win if I could keep the front end down! I have only drag raced my two 4 strokes a couple times (with a friend riding one) . With practice, the 350 would probably come out ahead, but only in the short, straight drag races.. I haven't ridden my 350X in a couple years now, so I am not positive on that. I just let my friends ride it. A 350X is awesome, and definately worth owning.

 

Yes my machine is totally stock other than a K&N filter synthetis oil and 93 octane gas . I just raced the same guy again today and beat him again . I did let him win the first time today , Then we bet a tank of gas on the second race and double or nothing on the third race . In like an eighth mile I can beat him without useing 6th gear . Longer than that hit 6th gear and leave him , I do shift without the clutch and keep on the gas full bore and sit as far up as possible I do have to be careful to keep the front end down though . His is a 2000 400 ex . Its great when your 1200 . machine can beat a $5000 + machine .