350X engine in an '85 250R frame?

[Hedbngr18]

First off, this project is a few years down the line. So nobody get too excited! Also, I am sure there is a previous thread on this exact subject on here somewhere. But, I was on the phone with a friend the other day and after watching the 350X documentary on Youtube and decided that instead of building a 3rd 250R, I'd rather have a well suspended 4 stroke to cruise out in Occotillo Wells for my dirt loving friends that I tolerate. :rolleyes: It probably won't see the dunes very often, as I have two 3rd gen Rs and a 500 conversion already. If anyone could point me in the direction of any previous threads or users that may have some answers, I would be eternally grateful! Thanks all!

[fabiodriven]

Personal opinion, you'd be much better off re-suspending the X. Inverts in the front and I'm not sure what you'd do in the rear, but I don't see the benefits of the R frame out weighing the massive amounts of fabrication that's going to entail.

[yaegerb]

x2...get your forks and rear shock revalved and set up for you. That's as easy as sending it off

[DohcBikes]

First off, this project is a few years down the line. So nobody get too excited! Sounds like a plan.

[Dirtcrasher]

I have inverts and an Axis shock on mine.

It's amazing.....

[atc300r]

It would take alot of fab work.Im putting a 200x motor in a 85 250r frame and I had to cut the engine cradle just to fit my mockup motor in.May have to cut it out completely.Doesnt Richard have a 350x with 250r swingarm and frontend or inverts on it.That would be the way to go.

[plevib]

Yup..... plus why would you cut up a good trike. ;) :lol:
234146

[plevib]

But in all seriousness you will run into issues with the frame being in the way of your intake, but I say go for it! You'll have to make goofy intake but mine works wonderfully. But at this point it seems like more of a pipe dream... (I've got plenty of those too)

http://www.3wheelerworld.com/showthread.php/177712-1984-ATC500X-build!!!-NEW-ride-video!

[Hedbngr18]

Personal opinion, you'd be much better off re-suspending the X. Inverts in the front and I'm not sure what you'd do in the rear, but I don't see the benefits of the R frame out weighing the massive amounts of fabrication that's going to entail.

Well, the main idea for this build is that I already have the R frame and rear end. Would I be better off possibly trading the R frame for an X and starting from there? I know the R is not only thicker, but just more solid all around. I am definitely a fan of the no cutting and welding idea as I have no welding ability. If the R swinger fits, I would much rather go that route. Ideas?

[plevib]

Well, the main idea for this build is that I already have the R frame and rear end. Would I be better off possibly trading the R frame for an X and starting from there? I know the R is not only thicker, but just more solid all around. I am definitely a fan of the no cutting and welding idea as I have no welding ability. If the R swinger fits, I would much rather go that route. Ideas?

Well, I don't mean to be a debby downer but you're not going to do a motor swap without welding anything. .....

[oldskool83]

R tank will hit motor.

[JesseA420]

sell the 250r swinger and frame, use the money to setup suspension on 350x properly.
done.

[oldskool83]

I'll buy the 250R swinger and and frame. See done deal.

[Dirtcrasher]

I wouldn't even try to put a 350X motor in an R frame.

If you go the 350X route, the invert fork auctions run about 250$ on EBAY. Rebuilt and shortened with new seals for 300$, Then you need to buy custom fork clamps ( IDK what these guys charge now but they are all very trustworthy people with great products from Jason Hall, Richard (KASEY) and or another member Louis Mielke).
Also a 350X stem, fork guards, brake hose guide and an entire set of front brakes with the rotor, caliper, pads, master, bracket, line etc etc. And a rotor adapter for a 350X or 250R front hub.

The rear shock, can be changed to a 250R and valved better by Milner Brown (Onformula1). I'm sure he has other options as well.

I bought a custom AXIS with a 350X top mount and a 450R lower with hi and low speed compression and rebound damping and the "soft ride" system. I modified and used a 08 TRX450 aluminum swingarm which is about a plus 2.5" longer than stock 350X.

The bottom of the 350X frame needs a very stout mount for the linkage and lots of gusseting is required. You'll need all that linkage as well.

I have 4000$ in suspension alone.....

It's not an easy job. You need to duplicate how far back and down the linkage hole goes or the geometry is all wrong.

[fabiodriven]

I didn't have time to reply earlier but I was going to recommend you ask Dirtcrasher what to do.

[Hedbngr18]

I'll buy the 250R swinger and and frame. See done deal.

If you're serious, I would like to sell it. You would have the choice of an 85 or 86 swinger. Or both if you like! :naughty: If not, I'll find someone locally that may want them. I need the room (and the $) to start on the 500 conversion. Anyone who may be interested, PM me!

[oscarmayer]

if your going to stuff an engine that big in there, why not look at a CRF250R? close to the same size but 2-3Xs the performance and is water cooled so you can run all day and not over heat.

for suspension, you can look at custom triples and I would get a metaltech custom swing arm made. would cost around $600-$650 and you can get in in any length you want. we are running a custom done one on the Baja trike that will use a 86 250r hub and brake assembly and bolt to the 350x chassis. Those guys do great work!

rear shock? talk to Milner, he can build what ever you want. Onformula1

take the stock 250r and get it modified with better springs, better piston and valve design, longer clevis for more travel, and re-anodized for strength and wear.

[fabiodriven]

Ya actually don't talk to Milner.

[Hedbngr18]

Wow! Thanks for all of the advice everyone. I really appreciate it. I think I'll just let the frame and swing arm go to a needy enthusiast and buy a complete 350X down the line. Unless I hit the Powerball. Then I'll have my TPC setup I've been drooling over for the past 2 months. Thanks again y'all!