What's up. Atc250sx

[Heaven]

Well, two days ago I got my first bike. A 1985 Honda ATC250SX, Ive been riding it since I was a kid and now its finally mine. Its got superswampers on the back, and a few custom mods, but nothing special. I want to know what I can do to this thing to make it that much better. My granpa, who had it before, messed up and put duralube in there, is there a quick fix for that? Well im new here so go easy one me, thanks!

-Andrew

[atc350xer]

Welcome. Don't know what kind of mods you're looking for, but a 1986 TRX250 quad swinger will bolt right on... it's 2"-3" longer than the stock one. If I still had my SX, I'd do it.

[Dirtcrasher]

Why on earth does an SX need an extended swinger if all is well?? It certainly won't flip over backwards by accident...........

The 200X front end gives you the best bang for your buck and a disc brake.

What did he put Dura lube in?

[Xpress]

Put an aftermarket air filter on it, and you're done :)

BTW, I thought the SX was shaft driven???

[fabiodriven]

I'm guessing the Duralube messed up the clutch.

[ailll1]

Why on earth does an SX need an extended swinger if all is well?? It certainly won't flip over backwards by accident...........

Yes it could flip backwards. Tried to follow one of my buddy on his BR getting up a steep ditch covered with loose rocks and it flipped right over me.
I couldnt lean any further up front, the tires spun and suddendly got traction, and the front wheel went up real quick. Fortunately, the muddy water absorbed the trike and I didnt hurt myself.

BUT I agree with you, it wont flip over with power or going up a long and steep hill if you can keep your speed.

[TheRealFatShady]

I'd like mine extended for some of the steep hills where I ride. It feels really tipsy, and the 25" tires rub the fenders on jumps/bumps.

But for upgrades mostly just seat cover, bars, snorkel, exhaust, 350x carb, 200x front end.

[Heaven]

Thanks for all the advice, Im gonna go with a 200x front end and a couple other things yall mentioned. Now about the duralube, he put it in with the oil, not knowing it also lubricated the clutch. It slips, real bad, I was just gonna take it apart and clean it out with some kerosene or carb cleaner, unless there was an easier way. Ill put a pic up tommorow.

[jpatey44]

you cant extend a 250sx because there shaft drive

[Name Brand]

you cant extend a 250sx because there shaft drive

Yes, you can. The '86 TRX250 is also shaft drive.
See how I did mine in the SX link in my signature below.

[MrPretty]

This guy has a swingarm from a '86 Fourtrax250 on his.

http://www.3wheelerworldforums.com/showthread.php?61999-250sx-12-2-update-broken-and-fixed!

[MudBug]

Just use the TRX driveshaft I assume...

[wisconsinite]

i'm finding this longer wheelbase sx idea very interesting. i always thought mine would handle better and maybe ride a little smoother with a longer wheelbase, but had no ideas how to do it with shaft drive. might hafta start watchin ebay.

[TheRealFatShady]

long night so I must be overlooking something, but can't you just get a longer driveshaft with the same splines, such as a TRX250 or maybe other models, and cut/extend the stock SX swingarm the same amount?

IE 2" longer shaft = 2" to extend swingarm. I really want to keep my SX but I want bigger rear tires.

[wisconsinite]

i supose you could, seems simpler to me though just to swap out the swingarm too. from what i've read so far on this thread and the links about it, it would be a direct bolt in except maybe the shock mount?

[Name Brand]

long night so I must be overlooking something, but can't you just get a longer driveshaft with the same splines, such as a TRX250 or maybe other models, and cut/extend the stock SX swingarm the same amount?

IE 2" longer shaft = 2" to extend swingarm. I really want to keep my SX but I want bigger rear tires.

You could do that; it may be difficult to keep the swinger lined up while welding it back together. That's four weldments to keep straight. (2 extensions; one on each side)

The big advantage of using the entire TRX swinger and axle assembly for the '85 SX is upgrading to the better sealing rear brake to prevent water intrusion. The '85 rear end assembly has to be completely taken apart piece by piece for removal. The '86 and newer style comes apart in sections and is much less labor intensive to work on. I have to believe the extra wheelbase helps smooth the ride; I don't really notice between the Bear Claws and the rough terrain I find myself on. Also; when running larger tires the TRX diff has a lower gear ratio than an SX to help turn them at slow speeds. For a brief time I had some 21'' tall tires on the back with the TRX diff. It was a torque monster that would hillclimb fast in third gear, but I had a very slow top speed. The 25'' tires work great with the TRX ratio on mine.

The lower shock mount is what needs fabrication to work. If you try to put the shock in between the upper SX frame mount and the lower TRX axle mount it will run through the battery. I made a pretty nice bracket that bolts onto the swinger and puts the lower mount about where it would be on an SX. This works very well, but I am going to try a different solution on my next SX...

If you are doing this to run 25'' tires on the rear, your front is going to be low. I put a 25x11x9 on the front of mine; it barely fits! I narrowed a rear rim from an '86 TRX250 to almost 8 inches wide. You could buy one, I guess, I didn't want to wait! I'm not sure how a 200x front would raise it or not.