Supercharged American Motorcycle
American sport bike enthusiasts’ affinities often run Italian and Japanese. From an American perspective, Buell has also entered the mix and continues to gain momentum with the Helicon-powered 1125R, as well as the air-cooled Harley-Davidson powered variants. But, many demand a more exotic and exclusive American superbike… that "Bimota" of America. Now, after significant development, the American Roehr 1250sc has finally pasted EPA approval and is ready for delivery.
We had the chance to meet with the creator, Walter Roehrich, who has been building bikes as a labor of love for over 15 years. You can learn more about Roehrich in our June/July 2009 issue of Ultimate MotorCycling magazine, and by listening to the radio broadcast link below. But, because we had a chance to ride the motorcycle, we wanted to bring it to you right away.
The Roehr 1250sc is built around the modern, Harley-Davison Revolution engine from the V-Rod. This motor was originally developed by Porsche and Harley engineers, around the VR-1000 Superbike race effort. The liquid cooled, double overhead cam, internally counterbalanced 60-degree V-twin (not the H-D traditional 45-degree) engine has a displacement of 1250cc (up from the original 1130cc when introduced in 2001). But, what is so very special about the Roehr engine is that it is supercharged.
Unlike a turbocharger, which may have some lag due to the required turbo "spool-up" time, the Roehr supercharger runs directly off the water pump drive shaft, which has been replaced by an electric air compressor. The result is the healthy production of broad, linear power. On paper, this engine is at the heart of what promises to be the most powerful American sport bike.
After extensive development and testing, the Roehr puts out a claimed 180 hp @ 9500 rpm and 115 ft/lbs of torque at 7500 rpm. To put this in perspective, the standard V-Rod claims only 84 ft/lbs, the Ducati 1098 claims 85 ft/lbs, and the Destroyer (Harley’s 6.7 second drag-bike) 97 ft/lbs.
"I have been building bikes for over 15 years and now the culmination of my dreams is about one month away from final street legal approval," Roehrich says. We can’t help but be distracted by the 2009 Roehr 1250sc as Walter tosses us the keys for a first ride. Produced in limited numbers, this is a true American exotic with top-shelf European appointments including Brembo, Ohlins, Marchesini, and Akrapovic.
The motor fires instantaneously and idles with a refined and tamed rumble. After familiarizing myself with controls and gauges, the feel is familiar to other exotics we have ridden. The reach to the bars places you in forward and ready-to-sport-ride position. The seat is a bit wide but once on the pegs your legs tuck-in nicely for the anticipated speed rush.
The engine response from the long-throw Roehr throttle is flawless. It runs from just off-idle straight to redline, and bounces off the rev-limiter before you know it. It is in its powerband most of the time as it is so very wide. Deceptive as it may be, looking down at the speedometer tells the true story; this is one fast machine.
Around corners the 1250sc steers with monorail like precision; at 425 pounds dry, it is not a light bike, but it is well balanced. The broad power makes it easy to run it hard out of the corners, almost regardless of gear selection. The bike handles the tight stuff just fine, but gives some indication that she wants to stretch her legs and might prefer some faster sweepers and longer acceleration runs. The Brembo brakes perform as well as you’d expect. The back-torque limiting clutch is most "slippery" while downshifting from higher speeds with higher forces.
Unfortunately, our ride in Southern California was brief and our appetites for an extended ride in a wide variety of circumstances is forthcoming. For more information on the Roehr now please listen to our live radio broadcast with Walter Roehrich on the Motorcycle Radio Network.
Leathers: Alpinestars Octane
Gloves: Sidi Design Series Power Glove
Boots: Alpinestars S-MX5
Photography by Don Williams
Engine: Supercharged, liquid-cooled, DOHC, counterbalanced, 60-degree, V-twin
Bore x Stoke: 105mm x 72mm
Compression ratio: 11.3 / 1
Transmission: 5 speed
Clutch: Wet, multi-plate, hydraulic actuation, slipper type
HP/Torque: 180hp @ 9100 RPM, 115 lb/ft torque @ 7600 RPM
Final Drive: 520 O-ring chain
Chassis: Modular Chromoly steel and aluminum
Chassis Type: Composite beam frame, 4130 steel / 6061 aluminum
Wheelbase: 56 inches (1422mm)
Rake/Trail: 23.5deg. / 89mm
Seat Height: 31.5 inches
Dry Weight: 432 lbs. (196kg)
Front Suspension: Ohlins 43mm fully adjustable upside-down fork with TiN
Rear Suspension: Ohlins fully adjustable linkless monoshock
Front Brakes: 2 x 330mm semi-floating discs, radially mounted Brembo 4 piston calipers.
Rear Brake: 245mm single disc, with 2 piston Brembo caliper
Front Wheel/Tire: 3.5 x 17 forged aluminum 10 spoke Marchesini, 120/70 ZR17
Rear Wheel/Tire: 6.0 x 17 forged aluminum 10 spoke Marchesini, 190/55 ZR17
Fuel Tank Capacity: 3.2 US gallons
Reserve Fuel: .5 US gallons