85-85 250r engine in 88 frame

Reply Subscribe

Thread Tools

Search this Thread

Jul 17, 1999 | 11:50 PM

Matt Ruszkiewicz

Thread Starter

Weekend Warrior

Joined: Jul 1999

Posts: 12

Likes: 0

I am thinking about building a 250r racer. But around my house their are no R's for sale. So i am going to go to a bunch of salvage yards and buy a 85-86 atc250r, and also try to find a R frame in good conditon with a front end in good condition. So i was wondering how much different the 85-85 atc250r engine id different from the TRX engine. Will my conversion work? I will also be buying parts from the classified ads onthis wed page. I also can't see buying a trx250r for 3500 that is stock, and then taking all the stock parts off, when i modife it. Any help will be greatly appreciate.
Matt

Jul 18, 1999 | 12:59 PM

Bud_Recor

Weekend Warrior

Joined: Jul 1999

Posts: 3

Likes: 0

The 85/86 ATC250R is the same exact engine as the 86 TRX250R. In 87 they changed the motor a bit, but the 85/86 atc engine will bolt in perfectly to a 86-89 TRX R frame.

Jul 23, 1999 | 08:12 PM

dosthoff

Trailblazer

Joined: Jul 1999

Posts: 86

Likes: 0

The motor from the 85-86 ATC's will bolt up perfectly, but the ATC has twin radiators like its dirtbike counterpart. The TRX's have a different radiator and you would have to track one down. I currently ride an 85 ATC with one of the sweetest R motors around. It has been sent out to DG performance and had a little "magic" worked on it. Because of the motor, I also kicked around the idea of transplanting it into an 86-89 R frame. I never have pursued the idea with a lot of effort, but I think you will find the procedure to be quite costly. You would most likely be better off buying a decent TRX and modding it. Good Luck!

------------------

Aug 2, 1999 | 04:42 PM

Tim250R

Trailblazer

Joined: Jul 1999

Posts: 32

Likes: 0

Matt,

It's me again. I built my R with an 85 ATC250R crate engine I found in the local classifieds. They are almost identical to the '86 TRX engine. I was told that the '85 engine was in a 'hotter state of tune' - meaning a little more advance timing and that 6th gear is a little taller for a little more speed. These engines bolt right in, work great with an 89 CDI (for a little better power curve), and will work perfectly with any TRX radiator. Once again I know from experience and go to my web site to find out more. <A HREF="http://members.xoom.com/TheATVPit">The ATV Pit</A>

Tim Thibodaux - '86 TRX250R (Bad to the Bone!)
<A HREF="http://members.xoom.com/TheATVPit">The ATV Pit</A>