Swing arm questions?

[Hutchracer]

I was wondering if somebody can help me with out I am wondering what the difference between the 86-87 and the 88-89 swing arm for the TRX250R. I am new to them as I've been a 3 wheeler diehard for years. I know they are different lenghts but what are the dimentions of them, and will a 88-89 swingarm bolt up to a 87 frame or are the that different? I just picked up a 87 project but some of the little things are starting to make me question why I took on another lol. Thanks to anyone that can help me out

[Allison55ex'er]

88-89 swingers are one inch shorter and aluminum where as the 86-87s were steel they shortened it to keep it from spinning out as much i believe. they do interchange alot of the questions have been asked already on here so you can find that information by using the search feature. I also just picked up a project quad and its getting torn down and im finding alot of things need to be replaced but i geuss what can you expect its 20 some years old but just hang in there I doubt you will regret it when you get her straightened out. I dont know if I will ever get another fourstroke after getting this R

[deathman53]

the major difference is the length and being aluminum in 88/89. 85-87 were 1" longer and steel. The other difference between the 85-87 and 88/89 is the 88/89 is solid across the frame and 85-87 have a motor mount in the middle, where as the 88/89 rear mount is in the frame. You can't put a 88/89 swingarm on 85-87 w/o welding a new motor mount in the rear of the frame. Most aftermarket frames put the mount on the bottom rail, not the S bend thats on the top of 88/89 frames.

[Hutchracer]

thank you for the info it is a bit hard it seems to find the info that your looking for using the search. That is what I wanted to know if the frames were different or just the fact that they were shorter and different material... I might need to look into the 450R conversion it looks like.

[deathman53]

you want to be aware that 450r swingarms are different lengths. 04/05 is the 88/89 and 06+ is 85-87 length. I'd just buy a -1 86/87 and transfer everyithing or a stock 88/89 and weld the rear motor mount to the frame. Keep in mind, the 88/89 swingarms use different dogbone bolt, brake stay bushing holder(bolt) and even the busing itself. I'd buy a complete 88/89 swingarm, if you will go that way. The swingarm bearings for 85-87 and 88/89 are the same as well as the end caps and seals, its just the long center tube and lack of 2 collar tubes, 2 extra sets of end caps and seals(that comes with the 85-87 kit).

Next question, is the head stay being used?? If not, get one and bolt it between the two sides of the frame. Its a matter of debate weather to bolt the head to it or not. I always bolt it to the head, also.

What trikes did you have?? I do mx on mine and have another one coming, one-off 09 atc450r, using mostly new and current parts, getting rid of 24+ yr old stuff for the most part. If all goes to plan, it looks to be a short list: front hub/axle, tripple tree, front wheel, front forks for now and if you consider a 250r axle/carrier/rear brake/antifade in the list.

[Hutchracer]

I have a couple of 200X for the wife and son a 350X and a 250R thats been getting restored slowly but surely. Also I never did ask but will a 86 ATC 250R swinger work it looks to be the same as the TRX as I do have a stock length one off a parts trike.

[deathman53]

the 86 is the same exact unit as 86/87 250r, for some reason it has a different part number. The 85 will work too, just a different carrier, axle and brake linkage.

[RyanWsly]

86atc will interchange, skid plate mounts are why they are different. got a 86atc durablue swingarm on my 88trx