250R experts inside please

[502SS]

New guy here trying to get all the info I can....
I've got an '86 R that was sitting for quite some time in a barn, and I need some replacement parts/info.
This bike was raced for most of it's life, and the 1st owner put an extended swingarm on. 2nd owner who I bought from, put a stock length arm back on. One of the "clamps" to hold the carrier is broken, so I purchased a different one.
Question 1. The bike sits crooked in the back, yet the frame doesn't appear to be bent anywhere. I have read that some people claim the '85 and '86 swingarms are not the same, yet others say they are? I have no idea what year the one on mine came off of. Could that be part of the problem?
Question 2. Can anybody tell me what parts are interchangeable (or probably a shorter list of what's not) between the '85 and '85 R's?
Question 3. What (if any) parts are interchangeable between the '86 ATC 250R's and the TRX 250R's?
I'm sure I'll have plenty more questions, but I don't want to over burden everybody with my first post

[Dammit!]

That's a big 3 questions.

1) Try to post some pics of the rear end so we can see what's going on.

2) Almost everything is interchangable but the swingarms ARE DIFFERENT. Rear brake setup is a little different, bearing carrier all different. You can use either one on either year but you have to change out the other parts with it. There are actually a lot of small differences between 85 and 86. Do a search on the forums here and you'll find plenty of threads on the subject.

3) Again lots of parts will interchange. It's been covered in depth. The search button is about to become your new best friend.

[deathman53]

1> 85 and 86 swingarms are nearly identical, except for the carrier, axle, rear brake mounting pieces
2> everything but the swingar related parts are interchange, also pegs and plates were different in 86
3> most engine and chassis parts are interchangable w/ 86-89 trx's, except the obvouis front end differences, and 88/89 had different peg mounts and a shorter swinger and motor mount on the frame. More stuff was different too, but its really obvouis.

[InPiEcEs]

1) '85 and '86 swingarms are pretty much the same, except that the '85 has a linkage to hold the caliper from turning, and the '86 has a stud with a nylon button.
On the 86, there is a slot in the caliper bracket that this button rests in. On the 85 there is an arm that bolts up to the swingarm from the caliper.

The swingarm is not your problem, unless it is bent. It is possible that the frame is tweaked, but not visibly. If the bike is tilting, it could be the rear wheel bearings, though I think you would notice that. Is the axle possibly bent? If it is crooked side to side, it could be the frame, or the swinger. Pics would help out, if you can get them.

You can bolt up any year swingarm to your ATC, with 85 needing an 85 rear caliper and arm, all others 86 and up are the same. 89 TRX is aluminum, and a different length, not sure of 87 and 88 TRX swingers.

2)The CDI box, and it's wiring harness have a different end on the 85. 86 to 89 are all the same, only 85 is different, so the CDI will not interchange to 86, but 86-89 will. Other than the headlight, which will interchange if complete. I can't think of anything else right now, but I know someone else will know from memory.

3) From the TRX pretty much all will interchange with the ATC, but the body/seat, frame, front suspension/steering, electrical harnesses (though you can change them to get them to work), radiator, and hoses, front calipers and hoses, rear brake pedal, footpeg mounts,( though I think the pegs are the same), and a few other things I can't think of right now will not interchange.

[phil53]

my 86 R sits the same way. I just put a little bit more air in one of the back tires to even it out. it sort of pulls to the right but nothing worry about on the dirt. been that way for over 5 years.
one of your fork springs could be losing tension, one fork tube could be higher in the trees. it could appear to be in the back.

[502SS]

Thanks for the replies everybody. The two things that concern me....
The front forks look straight, yet both angle to the right (like the bike is sitting at an angle), and the rear of the bike frame is about 1/4" lower on 1 side, and about 1/2" or so further to the right (from the back). After closer inspection, I do think the frame is hurt.
Like I mentioned, I do have an '86 swingarm coming, so my biggest concern was bolting everything to an '85 frame (I have 2 that I can pick up). At this point, I'm probably going to pick up a different frame and let this be my winter project.
Next question is....... how hard is it to swap in a CR500 motor I'm hoping that will be my next years winter project.
I was very curious about the TRX 250 interchanging parts, as it seems they still list quite a few drivetrain parts for them. Seemed funny that some manufacturers would list the same part #'s for certain parts, and other companies would not.
Thanks again