2001 ATC650X : Project Tri-Killatops

[josh383]

So I'll start off by saying that I need another project like I need another hole in my head, but what the heck, I wanna three wheeler.

I grew up with a 185 and a 200s and spent the majority of my time between the ages of about 9-13 on one or the other, depending on which one was currently mobile. I was about 13 when I first rode a 250r and always told myself I would have one someday, and I still will, Lord willing, but for my trail use I want a four stroke, and sorry boys, but the 350 just don't do it for me and the constant teardowns and fastidious maintenance of the 450r engines wouldnt be bad if I had time, unfortunately that's always in short supply.

So XR650R it is. I'm going to graft a trx450 swingarm into the 650's to keep the rear suspension geometry, and a 250r front hub with a 10" wheel. The bike stock has 27.8 degrees of rake at the forks, so I plan on taking some of that out with the triple clamps and avoid flipping the forks over so I can maintain a leading axle and use the caliper mounting holes. The forks are 38 1/2" overall, with 35 3/4' from the top of the fork to the center of the axle, I found the overall of the 85-86 250r forks is 37", but I did'nt find the distance to the center of the axle yet, but its looking like there should'nt be an issue, I could raise the forks about 3/4" in the clamps if need be.

I'm going to pick up the trx parts this weekend and then the fun begins!!



I'll ad some pics soon. Merry Christmas everybody!!

[Jmoozy27]

Hope to see this one built. It will be a first for me. Good luck.

[DohcBikes]

http://www.3wheelerworld.com/showthr...50L-conversion

[onformula1]

So I'll start off by saying that I need another project like I need another hole in my head, but what the heck, I wanna three wheeler.

I grew up with a 185 and a 200s and spent the majority of my time between the ages of about 9-13 on one or the other, depending on which one was currently mobile. I was about 13 when I first rode a 250r and always told myself I would have one someday, and I still will, Lord willing, but for my trail use I want a four stroke, and sorry boys, but the 350 just don't do it for me and the constant teardowns and fastidious maintenance of the 450r engines wouldnt be bad if I had time, unfortunately that's always in short supply.

So XR650R it is. I'm going to graft a trx450 swingarm into the 650's to keep the rear suspension geometry, and a 250r front hub with a 10x5 2+3 offset wheel. The bike stock has 27.8 degrees of rake at the forks, so I plan on taking some of that out with the triple clamps and avoid flipping the forks over so I can maintain a leading axle and use the caliper mounting holes. The forks are 38 1/2" overall, with 35 3/4' from the top of the fork to the center of the axle, I found the overall of the 85-86 250r forks is 37", but I did'nt find the distance to the center of the axle yet, but its looking like there should'nt be an issue, I could raise the forks about 3/4" in the clamps if need be.

I'm going to pick up the trx parts this weekend and then the fun begins!!



I'll ad some pics soon. Merry Christmas everybody!!

Very cool, good luck!

It's cool you are going with the water pumper "R"

[josh383]

I think this may be the bike featured in a couple YouTube vids, mostly gopro footage during on road riding, very little of the machine itself f

[josh383]

Thanks onformula1, I have an 81 XL500 engine that's been worked over a bit with an overbore and valve job with some porting that I thought about transplanting into a reinforced r or x frame, but that was a fleeting thought.

I'm pretty confident I'm going to love this setup, I already love her big red pigginess as a 2 wheeler, time to give er that third wheel she deserves!

[josh383]

If anyone could get me the distance on a mounted fork from the top of the fork to center of axle on a stock 85/86 250r I would be very grateful!

[mdmike]

Check out Mark's street legal 650 conversion. He's done a ton of research into converting the big thumper to a 3 wheeler:

http://www.3wheelerworld.com/showthr...heels-Oct-2002

[DohcBikes]

Someone may be along again to let you know that his is a water cooled "R", not an "L" as if it matters. Hopefully it won't be the second link to a 650 3wheeler that the o.p. disregards.

[josh383]

I didn't disregard your link dohcbikes, the reply I posted included a video link, so being the leperous newbie forum guy that I am, a little blip came up stating that my comment needed to be approved by a moderator first.it was a YouTube video of the trike featured in your link, which I appreciate you giving me. And Im grateful for any and all advice, that's why I joined, so thank you mdmike for your link as well.

[DohcBikes]

Cool.

My personal advice is

[josh383]

I'm on my way back from Ohio with all the rear parts I need right now, pics tomorrow afternoon

[onformula1]

If anyone could get me the distance on a mounted fork from the top of the fork to center of axle on a stock 85/86 250r I would be very grateful!

Box stock 250r forks. Topped out.

It is 32.5" from top of the cap flat to the center of the axle.

[josh383]

Thanks Milner, that's on the bike with weight on it?
If it is that would leave me about 3 1/4 longer than that in this stock setup, I'm just thinking that it would be good to try and match the factory length of the 250r.....I know there's at least a couple different ways to fix that, and I'd rather keep as much travel as possible, would it be best to design the triples in such a way as to make that adjustment? Don't have time to think on it now, taking the kids to see Star Wars.....

[onformula1]

Thanks Milner, that's on the bike with weight on it?
If it is that would leave me about 3 1/4 longer than that in this stock setup, I'm just thinking that it would be good to try and match the factory length of the 250r.....I know there's at least a couple different ways to fix that, and I'd rather keep as much travel as possible, would it be best to design the triples in such a way as to make that adjustment? Don't have time to think on it now, taking the kids to see Star Wars.....

That measurement is "topped out" on the trike would vary depending on the weight of the trike, spring rate and spring preload.