Need help with an 85 250SX

[Trackburger]

Picked up a decent 85 250SX, I have never owned one of these models before and have not bought the manual yet.

I noticed the axle nut on the left rear tire was a little loose so I tightened it up and when I did it made the whole rear axle lock up so it wont even roll in neutral. Like the back break is binding. When I loosten the nut to hand tight it rolls just fine. The rear brake is on the right side, I cant see how tightening the left axle nut would have any effect on this. Anyone have any suggestions before I pull the rear end appart??? Brakes work fine no noise or dragging.... just locks up when I tighten that left axle nut.

Thanks in advance!!!

[Trackburger]

Ordered some new brake pads as I figure when I pull everything apart I might as well change them while I'm in there

No one else ever have this issue????

[fabiodriven]

Just taking a stab, there has to be something binding. I think that's fairly obvious. You could have a wheel bearing that's stuck which would mean whenever you tighten the hub against the inner bearing race it's not going to move. Loosen the nut, and the axle is now spinning inside the inner race, which is bad. This is all just in theory, I see nobody else has replied so I figured I'd give it a shot. What you have to do is take things apart and inspect. You definitely have a problem.

[Trackburger]

Gottcha, Yes I definitly just need to take it apart and see whats going on. I just wasnt sure if it was a common problem and I could order something ahead of time. Thank you for your help, I will start in on it this week and take oictures of what I find to hopefuly help someone else in the future.

[Onetrackmind]

Here is thought from a relative nubie to all of this. I have purchased two 85 trikes (250r and 350x) in the last year and have had to rebuild the brakes (front and rear) on both machines. The common threads to all four brake systems was:
(1) Frozen Pistons in the calipers and
(2) Completely corroded and frozen pivot pins

Either of these items could possibly be coming into play with your 250sx as well. As you tighten the anti-fade, you are pulling the axle assembly toward the brake caliper. If you have frozen pistons or no play in your pivots (not sliding in or out), you could be bulling the disk up against a stationary brake pad.

You could rotate the rear caliper up off of the disk to see if you have anything frozen before you start tearing stuff apart.

Again, I am no expert...just a thought from a simple mind. Hope it helps.

Oh, and you can get your service manual here:

http://www.oscarmayer.net/atc/manuals/

[fabiodriven]

Yeah the SX is shaft drive with a mechanical drum brake. No anti-fade, no calipers, no pistons, no slides, totally different setup.

[Onetrackmind]

Got it... Please disregard my ignorance of the bike [emoji3].

[Trackburger]

LOL, its all good, thanks for thrying!!! This is all new to me too, restored 3 250R's and a 350X myself.... this is my first shaft drive. Will update this week (maybe tomorrow) when I tear it apart. I have a feeling the axle is being pulled to the left causing the shoes and drum to bind.... previous owner must have had apart and forgot a piece. Thanks again!

[Flyingw]

On each side of the axle is a bearing stopper. If one or both of those are missing then the axle nuts will pinch the axle. The only way of knowing if they are there is to remove the axle tubes (left side axle tube and right brake panel). Also, it very important that the bearings in the left axle tube are set to the right depth (10mm below the outside lip of the axle tube. If the bearings are set all the way to the bottom of the axle tube then it shifts the axle to the left about 3/16". If the trike is pulling to one side, get a dress makers tape and measure the outside circumference of the tire. Inflate the tires so both sides are the same circumference. Do not inflate to tire pressure. Tires vary at how much they stretch.

[Trackburger]

Nice!!! Thats what I was looking for. I will be taking it apart later this week so I will look for the bearing stoppers and ensure the bearings are set to 10MM. I wanted this type of info to know what I was looking for during disassembly vice just tearing apart and not knowing that I should have checked depth. Thank you so much and I will post what I find!

[Flyingw]

The bearing stoppers are not the same but they only go on one way. Both axle tube need to come off along with the brake panel. The right side bearings are retained by a snap ring on the end of the axle tube but unless you are replacing the bearings, you shouldn't have to remove the snap ring. The right axle tube will come out with the brake panel. Since your axle is going to be out, you might as well replace the axle bearings and clean the axle. Get all the crud off of it and hit it with some primer or anything to protect the metal.

[Trackburger]

yeah, I figured thats the best route since I'm in there anyway.... spend a few extra bucks on the bearings and have the peice of mind its good. Thanks again!

[Trackburger]

Thanks again flyingw... Ordered a new C-clip since mine was missing as well as the left and right axle collars. Replaced all the axle bearings, replaced the right hub as the bad bearings that were in it gouged the heck out of it... also got a newer brake drum and new shoes and cables... All works as it should and no more issues.!!!! I can ride again!!!!

[Trackburger]

Here she is... now I need an 85 200X front brake assy!!!

[Flyingw]

ALRIGHT!!! Good job. Enjoy the ride.