I love my 85 R. It really is a good tail bike and it rips on top end. Mine is stock but if I do decide to hop it up my possibilities are endless.

 

The 2-stroke ATC's from the 80's are insane! I race a TRX250R and I gotta tell you I've gotta hang on for dear life when I ride my friends ATC 250R. Don't get me wrong I can hold my own on a trike because thats what I started out riding when I was 4 yrs old but you boys with your fully modded 2-strokes ATC's have some serious testicular fortitude!

 

Last time i checked the Tri-Z wasn't much faster,if faster at all then a 350X.

 

First off, let me tell you that I'm a Honda guy. Anyway, I would think about what you want the bike for. The 350X wins if you want a reliable bike for the woods. It does suck to start when it's hot, but it's a great all around woods bike. The Tri-Z and Tecate are good bikes, with the Tecate being the fastest of the three 250s (ATC, YTZ and Tecate), but the Tecate and Tri-Z are getting rare. They are and will be a good collector bike, but parts are getting hard to find. The reason the 250R is so good, is because of the popularity of the TRX. You will be able to get more mods and replacement parts for a longer time. Almost 20 years after the cesation of production of threewheelers, I would think about how hard it will be to get parts before I buy......

As far as performance (speed, handling, etc)....stock....

86 Tecate
86 250R
86 Tri-Z
86 350X

Modified, I would say that the 250R takes it by far...you can do anything to the motor in today's marketplace. You can make it a 400+cc motor, pushing almost 80HP if you want to. The Tri-Z and Tecate can't do that because they weren't continued in a 4wheeler in racing for the past 15 years. There aren't as many options available anymore for them. The 250R is the best option you have today if you want a 2 stroke threewheeler to ride everyday.

debate it anyway you want, but that is how it is......according to mags and races over the past 15+ years etc.

Cheers!