2014 MX build

[Boatright]

New to this site, I'd like to get more ideas and feedback on my build. 89 frame fresh blue powder but i'm about to gusset.
+3 dc-4 arms
20" float evols
ESR 310
450r lt elka stage for with link
-1 lsr swinger
+4 tusk axle


I have to do my best to make this rear shock work.

[jcs003]

Welcome to the site.  You got a great start.

John

[Fear250r]

Welcome aboard!  Post up an intro of yourself in the intro section!

Make sure them shocks are set up for +3's my friend!


Jesse

[rk88r]

Welcome, the linkage conversion will be interesting.

[havinnoj]

Welcome to the site!  What are your plans for the motor?

[Boatright]

Welcome aboard!  Post up an intro of yourself in the intro section!

Make sure them shocks are set up for +3's my friend!


Jesse

they are, thanks.

[Boatright]

Welcome to the site!  What are your plans for the motor?

ESR 310 non pv trx9 port, hot rods crank, v force pro series reeds, fmf fatty.

[Victork]

Welcome aboard!

[havinnoj]

ESR 310 non pv trx9 port, hot rods crank, v force pro series reeds, fmf fatty.

Cool.  Are you going to race this R or just building as a project?

[mx250r91]

I used the same shock and linkage a few years ago for my XC build. The top shock mount had to be lowered and moved forward to get the shock and linkage geometry correct and extended/compressed lengths for 20" tires. I still ended up cracking the airbox a bit even after raising it. I think the sprocket guard helped a little. This combination works good. Very smooth but little progression.

[Boatright]

Cool.  Are you going to race this R or just building as a project?

yeah its strictly motocross. A class locally C in nationals.

[Boatright]

I used the same shock and linkage a few years ago for my XC build. The top shock mount had to be lowered and moved forward to get the shock and linkage geometry correct and extended/compressed lengths for 20" tires. I still ended up cracking the airbox a bit even after raising it. I think the sprocket guard helped a little. This combination works good. Very smooth but little progression.

This is perfect, what did you do with the front of the linkage? aluminum spacers? what swingarm?

[mx250r91]

This is perfect, what did you do with the front of the linkage? aluminum spacers? what swingarm?

Steel spacers in the front linkage. The swingarm is an 88-89 Roll Design, the linkage mounting point has been moved rearward approx. 3/4" to match the 04-05 450R swingarm.

[Boatright]

Steel spacers in the front linkage. The swingarm is an 88-89 Roll Design, the linkage mounting point has been moved rearward approx. 3/4" to match the 04-05 450R swingarm.

Okay sorry for all the questions I really want this to work. Was it completely needed to move the top and swingarm shock mount?

[mx250r91]

Okay sorry for all the questions I really want this to work. Was it completely needed to move the top and swingarm shock mount?

Yes to make the shock and linkage work as they were (I didn't want to have a custom shock made). If I used the 250R swingarm and shock locations, the shock clevis bound up on the rear linkage and there was too much up travel with 20" tires. You might be able to get away with it for 18" tires (MX) but you need to go through all the measurements and calculations to get it right.