Anyone who has ridden an electric dirt bike would understand the limitations of most stock e-motos in the current market. If you prefer to keep your wheels firmly planted on terra firma and rip it up on trails or daily commutes, then stock e-motos would be well suited. If you’re a born and bred motocrosser who prefers life in the air, you’ll quickly release the suspension, and in some cases, even the frame won’t hold up to the beating.
GritShift’s R&D pro, Rusty, is the latter. So he pursued the idea of taking all the best parts of a gas-powered dirt bike and converting it to electric. On a budget. With the bones of a Suzuki RM, he succeeded in creating a self-named, one-of-a-kind Suzuki RM-E and put it through possibly the hardest test in the 2023 Red Bull Tennessee Knockout competition – including getting some impressive placing results!
For anyone wanting to tackle an electric dirt bike conversion, or if you’re intrigued about the process, this will get you thinking!
Who is Rusty?
GritShift is fortunate to have someone very capable not only of riding dirt bikes (and winning races!) but also highly skilled in designing and developing parts to advance the sport of electric dirt bike riding. With his wealth of knowledge, Rusty has created numerous parts to improve electric bikes – many of which can be found on the GritShift website.
We interviewed Rusty about building his Suzuki RM-E; here are his inspiring answers:
The Suzuki RM-E
The inspiration behind it was due to the amount of parts I was breaking on my Sur Ron consistently. I wanted something with the chassis and suspension to handle MX tracks. My goal was to finish the project and be under $5000 USD to keep it comparable to a stock Sur Ron.
My only reason for deciding on a Suzuki RM was because I found a rolling chassis locally for $400 bucks and was interested in doing a budget build.
I’m not sure how to answer this question directly. But the first step in this was to figure out the motor, controller, and battery mounting points. Which I had help with from local rider Derek. He had already converted one recently, and we worked together on the project. He supplied the first mounts and battery box from his design. Then I eventually redid them to fit a bigger battery and be stronger as I had broken the battery box of the original kit and it could not fit the 2nd battery as I specced out a higher capacity battery that was a bit bigger.
Motor: QS 138 70H V3
Controller: VOTOL EM260
Battery: Eon 72V 42ah
I was after about stock 2-stroke power of 25 kW, but with the advantages of electric torque of a 450 and to keep the weight under 210 lbs.
The only challenge I ran into with the build was when the QS motor cast mounts broke off. I expected this was due to a loose bolt that I had missed coming loose after riding for several months on it, and I was able to get this rewelded on and reinforced and have had no other issues along the way.
Right now, the only limitation to the bike is on deep sand in top power mode; it will push the battery to heat limits. This can be bypassed by upping the heat cut-out settings in the BMS, but it will reduce battery life and increase cell degradation.
Most of the build was actually more maintenance and R+D modeling for the 2nd (replacement) battery box. I wanted the bike to look good, so I completely tore the frame down to bare steel so it could be sandblasted, powder coated, and rebuilt with all fresh bearings and lube.
Racing the RM-E at Red Bull Tennessee Knockout (TKO) 2023
The only advantage I see to gas bikes at this point is range and clutch. Clutch control would be a huge help in certain sections of TKO, and range is always a dilemma for e-bikes. I have to remember to pace myself at some points and not run full-out to increase range for some of the longer loops. This ironically seems to help my riding, though, as I tend to ride more consistently and smoothly like this.
The only thing I would do differently in the future is to utilize a different frame. A more modern aluminum split frame would be hugely beneficial to run bigger batteries. Bigger batteries could support more power and range. But I am not unhappy with the build at all, it is extremely reliable.
Not a lot. There are a lot of motor mount kits available for different frames. With a basic mechanical understanding of installing parts, this could be achieved.
Research, research, research! There are certain limitations to each frame with battery size and motor sizes, so this all can change based on your goals for the bike.
This honestly depends. Most stock e-motos lack proper suspension, which can be a downfall for motocross guys. But for woods and trial riding, the suspension is usually mostly adequate. If you’re a straight motocross guy, though, I don’t think there are many options that you would truly enjoy without completely building [out] a stock e-bike, besides [something like a] Stark Varg, Alta, etc..
GritShift’s Dirt Kings: Rusty’s Suzuki RM-E
If you’ve ever thought about starting (or finishing!) a project, this example should be the inspiration you’re looking for. This is the perfect sample of uniting both the gas-powered and electric worlds of dirt bikes.
Rusty’s RM-E shows that, with a little ingenuity, it’s possible to compete with the big dogs right in your home garage. It’s all for the fun of the sport, and Rusty observed his own riding start to improve in unexpected ways as he conserved power and momentum amid a pack of gas bikes at TKO.
The Suzuki RM-E might be a one-off, but that same eye for engineering goes into everything we build here at GritShift. From bar risers to skid plates, our goal is to keep you and your e-moto performing to your fullest potential. Check out our e-moto parts collection to see our latest creations.
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