The fact the supermoto came and almost went so quickly is one of the great mysteries of modern motorcycling. Here is a sport that, at face value, should be booming across the world because it answers a bunch of problems surrounding sporting motorcycles in the 21st century. Problems like, I want to road race but don’t have the money; I’m bored of motocross; I’m no good at flat track; there isn’t anywhere good to ride near my place, only go kart tracks.
Supermoto hit its peak about 10 years ago in the U.S. An ultra-competitive national championship with big name riders like Jeff Ward, Doug Henry and Chris Fillmore, factory teams, television coverage and X-Games races all made for one incredibly spectacular form of bike sport. The fact that the sport is so adaptable to changing environments makes its demise from our motorcycling conscious all the more remarkable, and sad.
So former staff member Jason Abbott and I thought, “to hell with that! Let’s build one and see what everyone else is missing out on!” We had a long term Suzuki RM-Z450 just sitting in the shop after our enormous 450cc shootout from Cycle News Issue 50, 2015, and even though Jason left for PR land at American Honda, I wasn’t going to let our little dream of dark lines and tabletops flutter away into the abyss.
THE GEAR
What does it take to convert your dirtbike to a supermoto machine? Not much, it turns out. The number one thing that separates the two is obviously the wheels, so to make our slide dreams a reality, we partnered up with Dubya USA who sent over a set of their absolutely stunning 17in aluminum Dubya-branded rims laced to the ubiquitous Talon hubs you’ll find pretty much anywhere in a supermoto pit.
Next we needed some tires, so Bridgestone sent over a set of Bridgestone Racing Battlax V01F soft slicks, similar to what you’d find on a 250GP racer. After we burn through these we’ll throw on a set of supermoto-spec BM03Z front and BM04Z tires and let you know the results.
Next were the brakes, so Moto-Master jumped on board and sent us a complete Supermoto race kit, which was originally designed for a RM-Z450 from 2005-2011 but still fits the current model.
THE CONVERSION
Before I start, let me just tell you that this was by far the easiest modification work I have ever done on a motorcycle. I’m a qualified car mechanic and am used to stuff not fitting, but the brakes and wheels we got from Moto-Master and Dubya USA bolted straight on with absolutely no modifying. The whole job took less than two hours.
The first thing to do was remove the front and rear wheels and the front brake assembly. It’s a simple two-bolt job for the front caliper, and we removed the master-cylinder and lever as one unit, replacing them with the Moto-Master 12mm radial master-cylinder, stainless steel brake line, brake caliper and caliper mount and front pads.
We used the original brake bolts from the RM-Z450’s stock front wheel to fit up the huge 320mm front disc, and with the Bridgestone slicks already fitted (this required a tube as the Dubya wheel isn’t designed to run tubeless), it was simply a matter of using the stock axle and mounting the wheel in between the forks.
At the back, we removed the rear wheel and sprocket, using the same Suzuki rear brake disc for the Dubya wheel but using a Talon 46-tooth sprocket compared to the Suzuki’s original 50-toother. For a while there I thought the chain would require cutting but the axle and the chain blocks fit snugly at the end of the swingarm. There’s not much adjustment left available, but I doubt we’ll be going any smaller on the rear sprocket anyway so I’m not too concerned.
With the wheels and brakes all tightened up, it was simply a matter of bleeding the brake fluid through up the front and we were done. Finished. In under two hours!
How was it!?
I’d never ridden supermoto before. I’ve ridden plenty of dirtbikes on the street, some, like the Husqvarna SM510, sorely tested the outer reaches of my license, but as far as the sport of supermoto goes, I am a total beginner. But I’ve done plenty of dirt track and road racing, so I figured I’d get the hang of it.
Adams Motorsport Park is just up the road from the Cycle News office so my colleague Adam Waheed and I figured that would be a good place for the Suzi’s first run. We kept the stock suspension settings from Suzuki because in this first run, I simply wanted to see how the bike performed with the smaller wheels and slicks. Suzuki runs the air fork with the RM-Z, so we’ll explore new some potential mods with this suspension in the coming months.
We managed to sneak in four sessions on our new toy, and let me tell you, this is about as much fun as you can have with your pants on! I was absolutely amazed at just how well this thing worked straight out of the shop. The Moto-Master brakes had stopping power for days with nice, progressive bite at the lever, although by the end of the day we’d already worn through a fair chunk of the brake pads.
The Bridgestone slicks didn’t get severely tested for two reasons – a beginner rider to the supermoto style and we weren’t allowed on the dirt section due to the go-karts we shared the venue with – that was a real bummer but it means we now have a perfect excuse to head back there next week!
Even with bog-stock suspension, the Suzuki tracked beautifully and turned on an absolute dime. Direction changes are almost telepathic even at this early stage of development, so I can’t wait to see how it handles when we get a proper set up.
Next up, we’ll be getting some custom graphics from Dirt Graphics, and delving into some suspension set up and see if we can get the yellow rocket working like a real supermoto.
