Supercharged exotica: The American-made Roehr 1250sc
With its supercharged Harley V-Rod engine and superbike-spec styling, suspension and chassis components, the Roehr 1250sc is one of the more interesting American-built motorcycles around. Conceptualised, designed and built by Illinois-based engineer, innovator and sportsbike fanatic Walter Roehrich, the Roehr 1250sc shows that cruisers and sportsbikes with chromed, stretched-out swingarms aren’t necessarily the only kind of motorcycle US riders want.
The Roehr’s 1,250cc liquid-cooled v-twin, with a Rotrex C15-60 supercharger, produces 180 horsepower at 9,100rpm (167bhp at the rear wheel, as per independent magazine tests) and 155Nm of torque at 7,600 revs. The gearbox is a five-speeder, the composite beam frame is made of a mix of chrome-molybdenum steel and aluminium, brakes are high-spec Brembo units, the suspension is fully adjustable Ohlins and wheels are Marchesini 17-inchers shod with Pirelli Diablo Corsa 3 rubber. The bike weighs 196kg dry and costs – now be prepared for this – US$42,500. Yeah, that is expensive as hell.
So what do you get for all that money? Steve Atlas at Motorcycle-USA recently had the opportunity to test ride the 2010 Roehr 1250sc and here are some excerpts from what he has to say about America’s finest:
The Roehr is kind of like a supped-up Mustang or Ford GT. It’s 100-percent American made and beating at the heart of the beast is a liquid-cooled, big-bore V-Rod engine with a supercharger on it. Why a V-Rod you might ask? ‘It’s basically the VR1000 Superbike engine of old but reengineered for the cruiser,’ explains company founder Walter Roehrich. ‘The engine is great and well-made, and can handle loads of horsepower being pumped through it. The only downfall is the weight. The engine itself weights almost 100 pounds and in a 400-pound bike that’s a lot. This is why having it make good, useable power was a key. As well as trying to make the rest as light as possible.’
A souped-up two-wheeled Mustang that isn't afraid of Ninjas and R1s...?
The Rotrex supercharger is designed to deliver air in proportion to the motorcycle’s driven speed, by virtue of a system that increases the speed of the SC-unit to match the bike’s engine speed. The idea is that as a result power delivery will be as smooth as possible and it seems to eliminate that aggressive ‘hit’ usually associated with forced-induction.
Power comes on from low rpm smoothly and gets the American-made 1250 moving with some serious steam. This type of power delivery is exactly what is needed to make it a fun and entertaining sportbike on the street. On the track, it certainly feels like a racebike but it is on the heavy side to be considered a pure track weapon. I wouldn’t hesitate to use it at a track day, although it needs some higher-spec tyres if you plan to push it hard. The Brembo brakes are very good and the suspension components have the potential to handle anything the average Joe can throw at it.
Seating position and ergonomics feel very much like a Tamburini-era Ducati. The reach to the bars is a bit stretched out, the tank is long and skinny, the riding position is aggressive and the cockpit itself is reminiscent of the Italian Twins. The steering is a bit heavy initially, but once set in the corner and on its side is very stable and solid, offering ample feel to the rider through the bars.
It handles very similar to the Ducati 1198 though it simply doesn’t have the gearing to keep pace with its Italian counterpart. Initial power is on par but it runs out quickly, as we were often hitting the rev-limiter while finding that happy medium between getting a good drive and battling to keep traction from the stock Diablo Corsa tyres. The trick is to run it a gear higher than you think and carry a bit more speed in order to keep the engine in the meat of the power.
This motorcycle was not intended to be a race bike. It’s a hand-crafted American-made superbike for people who are tired of following the crowd. It’s unique and it’s pretty fast, plus it gets around the track fine if you aren’t hoping to qualify for an AMA National. It may not be the bike to lure Gixxer punks away from Suzuki but it will appeal to a more affluent club. The rider who wants to be different, who wants to stand out from the crowd and be able to boast of a supercharged V-Twin and a list of top-shelf components that will keep any bench racer happy for quite some time...
For the full story, please visit Motorcycle-USA here
The Roehr is hugely expensive, but for those who want to splurge on an exotic, supercharged motorcycle that isn't exactly as common as a CBR600, the 1250sc just might fit the bill
Walter Roehrich talks about the bike he built...