Moto to XC: 2020 Suzuki RM-Z250 Off-road Build 4

We said it in our 2020 250 Motocross Shootout and we’ll say it again. The 2020 Suzuki RM-Z250 is not a bad bike. Sure, it is a little behind the other bikes in its class for raw performance and cutting edge technology, but, in fact, its power characteristics and nimble feeling make it an excellent candidate for an off-road conversion. So that’s just what we did. The focus was getting stronger, yet controllable power, more comfort from the suspension and chassis, and add some other off-road necessities.

This bike was built by former Mr. Know-It-All (Dirt Bike Magazine) and Dr. Dirt (Dirt Rider Magazine) and our current tech guy Scot Gustafson. He explains the build in his own words. 

The idea of the bike was inspired by an Endurocross bike I bought from Baja 1000 winner Kendall Norman when I worked for JCR Honda. The versatile bike turned out to be a fun forgiving Vet motocross bike and an able off-road machine when I wanted to ride trails.

Graphics were inspired by the classic Suzuki's of the late 1970's when the brand arguably produced the best bikes. The #104 was in honor of the first time I saw Roger Decoster at the Unadilla Trans AMA in 1978.

The engine features a FMF full system pipe, GET ignition, and JGR piston. I think we both agree the piston was a mistake. Maybe race fuel would have helped as the bike was really hard to start when it got warm with the higher comp piston and the performance gain wasn’t so much that it was a must. That being said, I loved the GET ignition. Easy to use, easy to program. I've enclosed a few screenshots from my phone. A Rekluse Torque Drive clutch pack was used for better power transfer and easier clutch pull.

The suspension was inspired by a Dirt Bike Magazine Honda CRF250X project bike from 2006. The bike was lowered 15mm with a Race Tech lowering spacer kit and matched in the front by sliding the forks up 15mm. The Suzuki KYB forks provided the height change without modification. The suspension was softened with .47kg springs, lower fork oil level 335cc vs 360cc, and an "Endurocross" revalve to handle MX and off-road use.

The chassis was improved with an 18" rear wheel to provide strength and cushion with a taller profile tire. The Acerbis skid plate provided protection and did not increase chassis rigidity because it was made out of high impact plastic (as opposed to metal) and used stock mounting holes. Renthal handlebar mounts were chosen to eliminate the rigid stock one-piece mount. Renthal 672 (older RMZ bend) Fatbars were used to raise the rider position 7mm and keep flex characteristic. Since no motor mounts were available for this bike a 6mm hole was drilled in the stock mounts to increase flex and motor mounts were retorqued from the stock 49 lbs/ft to 40.

An Acerbis chain guide was used to provide protection (stock metal chain guides bend on impact) as was a Rekluse clutch cover (much stronger than stock magnesium cover).

Finally, a Works Connection Elite Throttle tube and EZ123 Clutch Perch completed the controls to give a frictionless "Factory" feel. Renthal Full Waffle Soft grips were chosen because they provide the maximum cushion (ask any Baja 1000 racer and Eli Tomac).

Parts List:

FMF
Factory 4.1 Stainless Steel Full System    $749.99

Rekluse
Torque Drive Clutch pack    $349.00
Clutch Cover    $169.00

DeCal Works
Full Custom Graphics    $269.90
Seat Cover Gripper Ribbed    $69.95

Race Tech
Fork Springs    $129.99
Lowering Spacer Kit    $29.99

53TwelveSuspension
Fork Revalve    $175
Fork Fluid    $20
Shock Revalve    $175
Shock Fluid    $15

Dubya
Excel Rim    $216.69
Spokes    $99.95

Renthal
Fatbar 672    $93.95
Handlebar Mounts    $67.45
Grips Full Waffle Soft    $13.95
Twinring Rear Sprocket    $103.95
Grooved Front Chainring    $27.45
R3-3 Off Road Chain    $118.95

Acerbis
Skid Plate    $82.95
Tank Cover    $49.95
Chain Guide 2.0    $79.95

Works Connection
Clutch Perch 1-2-3 EZ Build    $155.85
Throttle Tube - Elite        $69.95

JGR
Piston    $299.99

GET
RX1 Pro Ignition $899.95