250r front on 350x?

[iceman atc]

Can I put 85/86 250r triple trees on a 350x frame??? I know 250r has tapered bearings and 350x doesnt, but will they match up if I use 350x bearings?

[jensenracing77]

i had my 350X triples bored to fit the 250R forks but just found out a couple weeks ago that you can press the tube out of the 250R and 350X triples and switch them. then you can put the 350X bearings in with the 250R triples with the 350X tube in them.

[iceman atc]

Cool I didnt pic up a frame yet but Ive got an extra set of 250r triples and forks laying around.

[audioworks04]

Does this affect the rake at all? I know that the 85/86 250r forks have built in rake, are the 350x the same? is there a noticable difference between the two?

[JohnR.]

I did this a few years ago on my 350X. You cannot simply press the stem from one set of triples and press it into the other, it won't fit. The 250R stem is bigger at the bottom. When I did mine I used the 250R bearing on one end and the 350X bearing on the other. I'm pretty sure I put the plate that was on the bottom of the 350X stem onto the 250R triple set up and used the 350X ball bearing lower set up. On the top I hammered a race out of a 250R frame I had and used a 250R tapered bearing set up. There is probably a bearing available that would allow you to use the race from a 350X taper bearing kit and a bearing with the right center hole for a 250R (maybe a stock R bearing will work in an aftermarket 350X race, I don't know). I had the parts lying around to do it the other way so that's what I did. I believe the R stem ends up being a little too long and you have to put a couple of spacers between the top triples and the spanner nut that gets covered by them. If you don't you will end up having to tighten the spanner all the time.

As for the rake, I just test fit a set up the other way around and I gained 5* of rake by putting an X front end on my R so I'd imagine you'd pick up 5* by going to an R front on your X. IMHO its pretty simple mod and its very worthwhile. The stock R front end isn't anything to write home about compared to the new stuff out there but its far better than the skinny front forks that the X comes with. I know you'll need the front brakes from the R and I'm sure the front hub from the R as well. I tried putting my X front hub on with the R front end and the position of the rotor relative to the caliper was a little off. Not a lot but enough to make it hang up and drag the front brakes. Your best bet is to get a complete front clip from an R along with the bearings and races from the frame. My 350 rides much nicer with the R front end and that decrease rake will help suck up big rocks and logs in the woods.

John

[Derrick Adams]

We did this a few years ago as well. When we did it, we just bored out the 250R triple to accept the 350X stem.

[Dirtcrasher]

^ You got it....... And then the rake is retained etc etc etc.

[JohnR.]

There is also very little material remaining when you bore the trips for that and also you don't get the 250R fork angle which is definitely more geared toward sport riding.