Roehr 1250sc - 180 HP Supercharged V-Twin
May 6th, 2008 by Paul Crowe - "The Kneeslider"
The Roehr 1250sc pre production prototype has been completed and plans are to begin production late this year. The bike is powered by a 180 hp supercharged Harley Davidson Revolution engine. This should be one extremely interesting motorcycle. I like the looks and I really like the blown Revolution engine. Final price has not been set.
Let’s see, a 180 hp supercharged American made V-Twin sportbike. Yep, I like it!
Press release:
06 May 2008, Gurnee, IL. USA. Roehr Motorcycles LLC is pleased to announce the completion of the pre-production Roehr 1250sc. The company is now working towards production commencing this Fall.
The 1250sc is powered by a specially developed 180hp, supercharged version of the Harley-Davidson* Revolution* engine, making the Roehr 1250sc the fastest and most powerful sport bike built in America.
European flair and American muscle are combined with the highest quality cycle components from world class companies such as Ohlins, Marchesini, Brembo, Akropovic and Pirelli. These components combined with the unique Roehr Bi-Metal composite beam frame contribute to the machines outstanding handling manners, offering quick precise steering response with confidence inspiring stability and rider feedback.
The Roehr 1250sc is proudly hand crafted in the USA and will be available in limited numbers. Final pricing to be announced when determined. Roehr Motorcycles is now accepting orders to reserve this exclusive machine as well as offering dealership opportunities.
More photos below:
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The following closeup is shown only to dispel the idea these photos are renderings. An engineer working on the Roehr 1250sc pointed out in a comment below this loose fastener you can only see in extreme closeups, something caught after the photo was taken.
Link: Roehr Motorcycles
Posted in American Motorcycles, Motorcycle Builders, Motorcycle Business
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34 Responses to “Roehr 1250sc - 180 HP Supercharged V-Twin”
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May 6th, 2008 at 11:57 am
This is very cool. Congratulations.
Excuse my limited knowledge of supercharged motorcycles, but what impact does that have on torque across the power band?
May 6th, 2008 at 12:12 pm
it looks very large!
May 6th, 2008 at 12:13 pm
Better than a turbo as it wolfs in air and fuel off the crank instead of exhaust (lag). The more compression you have the more torque you get.
I’d imagine keeping the front end down on this bike would be a task!
May 6th, 2008 at 12:15 pm
Hoyt,
good point. If a builder is going to tout significant power gains through forced induction, the first thing people are going to ask for is a dyno sheet. Otherwise it’s just a lot of blower whine.
I’m guessing you’ll see a huge gain across the rev range since the HD engines are known for their low-end torque to begin with. I’m also guessing blower gear ratio and blower size also is a factor. Then there’s the power loss from running another belt for the compressor, induction tubing length, etc…
May 6th, 2008 at 12:19 pm
No ‘nekid pics, too bad!
May 6th, 2008 at 12:52 pm
Nice! Is it just the paint job, or have they modified the fairing?
Looks much better than the red version we’ve been seeing to me.
Is supercharging allowed in Superbike racing? Are there any classes this would be elligible for?
There must be some ASRA/CCS classes it could run in, but I don’t know much about the structures in those races.
It should be eligible for Moto-ST, but they’d have to de-tune it to meet the horsepower limits.
May 6th, 2008 at 2:34 pm
Depending upon the type of supercharger, and the gear ratio of the drive will determine the amount of boost, and hence the torque increase. If this uses a positive displacement blower, they typically give significant boost at lower RPM and become somewhat inefficient at higher RPM, hence tapering off boost up high. If it were a centrifugal, then the opposite is typically true resulting in an engine that feels like a muscular version of the stock engine, giving small torque increases down low and increasing as rev’s increase. Both have advantages depending upon use.
May 6th, 2008 at 4:55 pm
Is it just me or does the top half of the fairing, the tank and the tail piece look like it was lifted off a MV agusta.
Also has there been any dimensions released wheel base rake?
May 6th, 2008 at 5:28 pm
There was a review a couple of months back on one of the major motomags about the V-Roehr (as it was called at the time). The designer was looking for sponsorship to get it into production. Looks like he got it. IIRC, they base engine is the same one as in the V-Rod.
Here are specs I’ve found online.
Technical Specifications:
Engine:
Type 2 cylinder, liquid cooled, DOHC, Counterbalanced, 60deg, V-twin
Displacement 1130cc
Bore X Stroke 100mm X 72mm
Compression ratio 11.3 / 1
Transmission 5 speed
Clutch Wet, multi-plate, hydraulic actuation
HP/Torque 120hp / 75lb/ft
Final drive Chain
Chassis:
Type Steel/aluminum composite beam frame, 4130 steel/ 7075 aluminum
Wheelbase 56 inches (1422mm)
Rake/trail 23.5deg. / 97mm
Seat height 31.5 inches
Dry weight 425lbs. (193kg)
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 monobloc
4 piston calipers. (Production version)
Rear brake 245mm single disc, with 2 piston Brembo caliper
Frt. Wheel/tire 3.5 x 17 forged aluminum 10 spoke Marchesini, 120/70 ZR17 tire (Production version)
Rear wheel/tire 6.0 x 17 forged aluminum 10 spoke Marchesini, 190/55 ZR17 tire (Production version)
Fuel tank capacity 3.6 US gallons
May 6th, 2008 at 5:58 pm
sounds and looks stupid quick! Can’t wait till they come out
May 6th, 2008 at 7:33 pm
Good point Uglyduc. It’s probably more of a Hayabusa competitor than a Ducati competitor.
. . . which makes it less interesting to me personally, but it’s still cool.
May 6th, 2008 at 8:26 pm
Yeah, all that added complexity and weight will just slow it down. That’s why the fastest and best handling bikes on the market run with kick starts, air cooling, magneto ignition, single carbs, flatheads, hardtails, etc…..
May 6th, 2008 at 9:23 pm
Smartass comment aside, I hope Roehr Motorcycles succeeds in doing what H-D could do but won’t.
May 7th, 2008 at 2:59 am
Only 3D render ? Not even a single “work in progress” real picture ?
May 7th, 2008 at 8:50 am
How did Alan Cathcart ride a rendering in the Motorcyclist article?
May 7th, 2008 at 9:28 am
Yeah, I believe that’s a real image of a real “work in progress” bike. It can be hard to tell these days, especially when real photos are composited on digital backgrounds. But who wants to see messy garages in the background anyway?
I definitely like this blue/silver one better than the first red one. It’s tough to do anything totally red, because of it’s association to Ducati. But the two-tone could be construed as MV Agusta.
I do see a blend of various Italian shapes. Not that there’s anything wrong with that, obviously it sells. I like Buell’s approach, though. It seems to me, if they were to attempt to compete against Ducati, they would aim to make something that looks nothing like a Ducati.
May 7th, 2008 at 9:41 am
nice machine
May 7th, 2008 at 9:47 am
As an engineer that is working on the 1250SC bike with Walter, I can assure you that these are all photos of the real bike. If you think not, zoom in on the top photo, and you will see where one of the fasteners in the center of the fairing was left loose right behind the front wheel, and no one caught it until after the photos were published.
The bike is not a “work in progress” any longer.
What you see is what will ship to the customers.
The only real detail that has not been settled yet are the mufflers on the production bikes, and that is days away.
The 425 lbs. is real, as is the 180 hp, and it will loose a little weight, due to increased use of light alloys on the subframe and lighter production bodywork.
Alan Cathcart tested an 1130cc non-supercharged prototype, and the production bikes are 1250cc supercharged.
The specs on the bike are on the web site, and they are correct.
Walter has literally turned his entire life upside down at tremendous personal risk and sacrifice to accomplish this, and it has been amazing to see the efforts every single day that go into this.
I only know of one other person that made the effort to design, cast, and build his own 2 stroke engine, get it running, build a bike around it, and demo it to everyone on the planet that would look at it.
In both cases, the 2 stroke bikes ultimately failed, but hopefully in both cases, the second will also succeed after switching to HD power.
And no, this post was not approved by anyone, and I do not get paid by Walter or Roehr Co.
I am an engineer that can be involved of my own free will, and provide what little help I can to watch someone succeed at something we all talk about but never have the guts to do.
Walter and the V-Roehr WILL succeed, and the motorcycling community will be a better place for it.
May 7th, 2008 at 10:21 am
mark - bimota use harley power? (joking - I know you’re referring to buell.)
my question is - who did your styling work? this bike looks quite good (fifty times better than the red prototype!) but if I saw this bike on the street with no prior knowledge that it was a production model, I’d guess it was assembled by a very gifted individual from a number of modified airtech bits. (not entirely a bad thing - see the durbahn 999….)
i wouldn’t take this entirely as criticizim (sp) because this bike is hot - if I had the cash and needed a bike like this I’d definately consider it, but still - given the work that went on under the skin…
question - is the dry weight taken from a scale loaded with a complete bike, or is it the “sum of solidworks data” number used by some manufacturers?
May 7th, 2008 at 10:40 am
Wasn’t this the bike that had an 80k dollar price tag?
May 7th, 2008 at 11:14 am
personally i find the styling very bland: generic japanese sports bike with a dash of 999. not my cup o’ joe.
my guess is that the target market will be the 1098R crowd, so a msrp in the $35-45k range.
good luck to them, though i am not sure, aside from the “made in america” bragging rights, you would choose one of these over say a duc, bimota, an 1125r, or even a 2008 cbr1000rr (both of these lat at a fraction of the cost)?
May 7th, 2008 at 11:32 am
If you think about it, this really isn’t all that different from what Erik Buell did 25 years ago . . . though technology is very different now compared to what it was then. But Buell also used a Harley engine, tuned it to his purposes and put it in his own, unique frame.
As long as Roehr can keep the price in a reasonable range, there will be consumers willing to pay for a very unique bike like this. And if they can bring in enough money to cover costs, they’ll be able to slowly ramp up, reduce the price and build into a more maintstream company.
That seems a much more valid business plan than Motocysz, for example, (at least this plan worked once when Erik Buell did it).
Good luck Roehr!
Mark L., can you comment on any racing plans?
May 7th, 2008 at 11:40 am
Rock on Mark!!!
This country is in need of more extreme engineering and high risk high reward projects.
May 7th, 2008 at 1:55 pm
As a motorcyclist who has been around a while, I think we’re entering something of a “golden age”.
With KTM’s new RC8, Aprilias new V-Four Superbike, BMW’s new Superbike, Ducati’s 1098R, Buell’s 1125R . . . MV Augusta, Bimota, Triumph, Benelli etc. etc. are we finally seeing an end to the era of: “You can have any sport-bike you’d like . . . as long as it’s a Japanese inline 4″?
I hope the race series continue to encourage this sort of diversity. I like what the AMA is doing with the modified Formula Extreme series and bringing a race pitting diverse configurations against one another to the forefront.
On one hand, we’ve seen some really great performing motorcycles over the past 30 years . . . on the other hand, is an inline 4 configuration really the only way to go?
May 7th, 2008 at 3:59 pm
So much for the golden age; you can have any sport bike you want as long as it’s an expensive, oversized, overpowered, under utilized money pit.
Give me a modern RD350.
-todd
May 7th, 2008 at 5:45 pm
todd Says:
May 7th, 2008 at 3:59 pm
“So much for the golden age; you can have any sport bike you want as long as it’s an expensive, oversized, overpowered, under utilized money pit.
Give me a modern RD350.”
-todd
Better yet, a modern RD400… FAR more utile than the 350!
May 7th, 2008 at 7:42 pm
As everyone can see from the un-altered PHOTOS, the detail work and quality of the 1250sc is at a VERY high level.
I have to respond to several of these questions.
Yes, I can comment on the racing issue. Walter very much wants to roadrace the bike, but that is not in the financial plan. It would have to be an outside effort entirely. I have had discussions with the AMA prior to the DMG buyout about possible class requirements. Moto-ST is a possibility, but superbike would be the ultimate class.
I know Walter would love to see the 1250sc race……
We proudly use Autodesk Inventor Professional 2008 mechanical engineering software, not the other products.
The weight is done just like you would do it. With a scale. Not from solid model data. That is used on specific parts during the FEA modeling, but it is for in-house use only. The weight will drop a little due to an aluminum subframe rather than ChroMo steel.
The bodywork is exclusive to the 1250sc. I know that an un-named person at a famous design house did a lot of design sketches, and some others, but I believe that the credit has to go to Walter on this. The bodywork is American made for Roehr, but I cannot disclose by who. (Not Airtech)
The bike is truly stunning from every angle.
As far as a “Modern RD350, Walter did that with the RV500, his own 500cc 2 stroke engine in a bike that weighed 315lbs. street legal, and made 116 hp. at the rear wheel.
It was a fantastic bike, and went over about as well as the Bimota VDue 500, (And being 87 lbs. lighter than a VDue, with 26 more HP, it could spank a Bimota so bad…..)
Everyone wanted one, (RV500 and VDue) but no one bought them, so I would say that answers the “Light-fast-handles good RD350″ crowd.
The 1250sc is competitive on the weight, exceeds the performance, and is similar in size with the ALL other open class sportbikes made by anyone.
Keep in mind, this is a DOT & EPA certified bike with a warranty.
I probably should stop here, as this is Walter’s story to tell, not mine.
Thanks for listening,
Mark
May 7th, 2008 at 9:01 pm
Thanks Mark I’m not even that interested in the Roehr but that was interesting information.
I’ve heard Roehr built two strokes before, it’s a same that didn’t work out. I always thought Victory should make a sports bike with a snowmobile engine (Polaris) two stroke in it. But I can imagine it not selling or passing emissions tests.
May 7th, 2008 at 9:17 pm
Must be magnificent to see a motorcycle you’ve designed and built being photographed for a press release.
May 8th, 2008 at 2:28 am
Mark L,
I would agree that the motorcycles people say they want and what they write checks for are two different things. I would add, however, that if people don’t want it in the first place then they don’t write checks for it either. So which one do you aim for? In my opinion, it’s best for the designer to just follow his own desires with passion and tenacity and not listen so much to what people say they want. Good design is good design, plain and simple. It’s like a singer in the right key. They either do or they don’t. People will buy things that attract them, even if it involves a bad business case or lack of service centers. I once heard P Terblanche say that motorcycles are fashion, nothing more.
Although I’m not too familiar with Roehrich’s RV500, and I don’t mean to discount his work in any way, but didn’t Bimota sell a few hundred v-Due’s? Aside from the efi problems the company had, it was/is still highly desirable and I believe people did buy them.
May 8th, 2008 at 3:48 pm
The point about the RD350 (and 400) was that Yamaha sold it for less than $1000 when a Ducati 750 started at $3000 and the Z1 was $2000. That means it would be about $5000 today. That’s a check I can write. How much was the RV500?
-todd
May 8th, 2008 at 4:45 pm
WELL, I AM MOST DEFINALLY A CHOPPER GUY. BUT I JUST LOVE ALL BIKE,S . I DO WISH THESE GUYS ALL THE LUCK.
May 8th, 2008 at 4:47 pm
P.S. ROHORN YOUR MY HERO”
May 10th, 2008 at 2:15 am
Great to see more U.S. company’s finally getting into the sportbike mix. Buell never really done it for me and the Fishcher doesn’t have enough power, plus quality doesn’t seem that great. This bike looks to have great attention to detail and quality. Just hope it stays close to the Jap. bikes on price, If not it probably won’t make much of an impact.I don’t think the aim should be directly at Ducati, because after all a Duc is a Duc. If they keep the price below the 1098(standard version) and close to the Jap big 4, it would probably catch on.I have a feeling though that this will be out of reach (price wise) for a lot of people. Great bike though!