A lot of you have wondered why Erik Buell never developed a V-Rod powered sportbike, it just seemed a natural. This BuellRod concept, by Luca Bar, is a “what if” design showing us what it might have looked like and it’s not bad at all. It has many of the classic Buell features, the perimeter brake, bottom mounted exhaust, though he does revert to chain drive instead of the current belt.
As Erik said when I interviewed him last year, the Revolution engine project was actually started by Buell but as the project evolved and specifications were developing, Harley Davidson took precedence and Buell moved in other directions.
Since that time, Roehr Motorcycles has developed the Harley Davidson Revolution engine powered Roehr 1250SC and Buell has gone on to bring out the 1125R but I still think this design has potential, perhaps all that’s needed is someone with the skill to put the pieces together, maybe Will from Fusion Motorcycles? It would be interesting.
Link: Luca Bar
John says
I like it.If they did a shrink fit of the chrome covers to look more functional instead of flashy and added fins all the way down the heads I would like the look better.Also I’m not sure about this but it seems they could possibly shrink the radiator size with more finning.And for all you Harley haters there is a Vrod called Badrod that has run the quarter mile with a time of 8.8 sec.It’s natuarally asperated, no nitrous, no wheelie bar on gasoline and uses all Harley parts in the motor.It is not the Vance and Hines pro stock motor for anyone who would suggest that.
Hugo says
Nice concept! I have two questions/thoughts though: the frame looks awfully thin for such a big, heavy and high-torque engine and where’s the fuel tank (in front of the air box so around the steering head)?
sohc says
So I have to pull the engine out to do valve ADJUSTMENTS? No wonder concepts always look good, they have zero engineering.
twin says
Great concept!
Erik Buell – skills bought by HD to get a ‘Harley to handle’
Porsche – skills bought by HD to make a decent ‘Harley Engine’
Ogre says
There’s a very good reason Buell never used that motor.
It’s too bloody heavy and a bitch to maintain (though as a Ducati owner I have no space to complain about that). Now, if they’d done more development of the VR1000 V4…
Pretty concept bike, though.
Chris says
What Hugo and sohc said.
It does look nice for a concept, although I’d be more interested in how nice a real-world version (with a fuel tank and/or realistic frame, possibly including the fuel tank á la the current Buell line) would look.
Ogre: what’s the V-Rod engine weigh, as compared to the air-cooled stock engine in, say, a Lightning?
cl
John says
What are you asking Ogre for?He doesn’t know what he talking about, he thinks the VR1000 is a V4
Charles says
Neat. I love that the lines are reminiscent of an early 80s Suzuki Katana.
Clive Makinson-Sanders says
Beat me to it charles. love that aspect.
sanglant says
John, you’re right that the VR1000 was a twin. However, Harley did have a beautiful V4, modular motor in development along with the Evo. They just didn’t have the cash to bring it out, and the Evo, so they went with what AFM had closer to production ready and set the course for the HD that we’ve had for the last two decades. If they had brought out that V4, it would have beaten the V-Max and the Honda Magna/Sabre (yes, that is spelled correctly, Sabre) to the punch. And with the V6 version of the engine, they would have had one of the best powerplants on the street.
But, it would have cost more in development, not just of the engine, of the frames and suspension, and it would have moved off their traditional customer base.
bR1an says
Charles, I am feeling the early Kat vibe as well.
Also, I’ve finally found out what happened to my old IT465’s swing arm.
John says
Sanglant, you are correct, that motor had a V2,V4 and V6 variant but Harley I believe also had an unrelated to that motor OHC 1100 cc. V twin prototype but it was at a different time, I think it was late 70’s or early 80’s.
JohninVT says
There are two problems facing anyone wanting to build a V-Rod based sportbike. 1st is the weight. The engine is huge. Second is the V angle. This concept LOOKS good but only if you ignore the fact the front wheel would destroy the radiator the first time the forks moved. You can’t tip the engine back without having to raise it several inches. Then you’ve got massive, heavy pistons pounding away belt buckle high. A high center of gravity plus a high polar moment of inertia would mean a miserable handling bike. It’s nice to dream but just because a V-Rod engine has more power than a typical HD doesn’t mean it’s any more appropriate to build a sportbike with.
hoyt says
JohninVT – I wouldn’t turn down an opportunity to ride the VRoehr.
I like Luca Bar’s Panther bike the best (except for the rear fender).
The centralized mass of the new Husaberg engine would make a very cool cafe bike.
Ry says
As far as the frame goes , other than the rear swing arm and minor mods, the frame looks similar to the Vrod frame that this engine is designed for, right down to the removable down tubes. A little thin it is not This is heavy wall DOM tube. It would be nice to see the fuel in frame design, however if I was to build this bike out of a Vrod , this is what I would like it to look like. The radiator and tire colision problem could be easily cured by moving it somewhere elese. Also I might like to add that many motor companies go to Porsche for their engine engineering expertise Ford to mention one.
Robin Day says
We at RADDesign in the UK are building a “Streetfighter” type machine using a V Rod engine. I had one of these machines and hated the chassis / handling but loved the engine and so went from there.
The chassis geomtry, wheel base etc is based on a Kawasaki 750 Zephyr, a machine which we feel handles very well for it’s age and for this particular application.
We have sourced complete, new, engines from Harley Davidson (via a US based dealer) and will utilise as many standard Harley engine ancilliary parts as possible.
The chassis spine (over the engine and down to the is manufactured from 2, 3″ diameter stainless steel tubes which basically follow the top / rear engine shape and are closed in to form an oval section. This structure is enormously stiff and stable while only weighting in at 29 pounds including all fixing locations, front and rear engine mountings which are bolt on billet machinings fitted with anti vibration bushings.
Ohlins front forks carrying a billet machined 7.5″ rim and 240 Avon tyre and Ohlins rear dampers attach to a stainless steel fabricated swinging arm carrying an 11.5″ rim and Avon 300 tyre.
The fuel tank is carbon fibre and part follows the frame “Spine” before flowing off to the dual seat.
The overall look is very minimalistic and basically polished stainless steel or black (rims, tyres and tank seat unit).
Those who have seen the work so far have described the machine as “gawjus”, release date for the project is during the first week in January ’09 and, hopefully, on this website.
We will lay down a total of 24 limited editions of this design.
JohninVT says
A V-Rod engine weighs 193lbs. Now add a supercharger and an exhaust that passes EPA regs to it. I think the Roehr bike is cool as all get out but there’s no way it weighs what they say it does. If you added up all the component weights you’d be well over the 425lbs dry weight they list. In fact, I think you’d find it was a lot closer to 500lbs than 425lbs. For comparison, a GSXR 1000 engine weighs 70lbs LESS and the bike has just as high or higher spec. chassis as the Roehr but weighs 415lbs dry. So the V-Rod as a sportbike hits some very real limits in terms of performance due to its’ basic architecture. The Roehr has a super short swingarm to get a 56″ wheelbase. Like… high side yourself to oblivion short, if it ever gets away from you. Any bike built around a V-Rod would have the same issues to overcome.
Nicolas says
Let’s turn the engine 90degrees and it will solve the problem of the wheel hitting the radiator and look like a super-guzzi-rod … 😉
Avec des “si” on met Paris on bouteille …
ROHORN says
It is so good to see the keyboard engineers sharing their vast knowledge and, more importantly, their years of experience with VROD engines and motorcycle design……
sanglant says
It’s so good that we have all those Roehr motorcycles on the road today to prove how wrong the nay sayers are, a year after it was “released” to the motorcycle press to drum up orders. Of course, now they’re 50k a pop, a price that keeps rising with each new offering.
JohninVT, the Roehr is light for what it is, but it isn’t a featherweight the way it could be with a better engine choice. It’ll scale in wet at around 440-450lbs if I’m guessing right.
Another problem for the Roehr is that it will have no range at all. Figure less than 100 miles per tank, unless they fix that tiny three gallon capacity it has now.
It will basically be another nice idea that was killed trying to meet production and DOT/EPA requirements. Roehrich’s earlier bikes were brilliant, but not production ready. And sadly, I don’t think the motorcycling consumer would have been ready for them.
Now, he may sell the 50 bikes he is/was aiming for. Honestly though, I doubt it. They certainly won’t be out on the road on anything approaching a regular basis. Then again, few of the Gurney Alligators are ridden much, either. I’ve seen exactly one on the road, and had the pleasure of talking to real rider that day.
John says
My thought exactly ROHORN
Hugo says
ROHORN what’s your problem? this is a concept after all, only one side view sketch so that makes it food for thoughts doesn’t it? BTW a lot of designing is done behind the keyboards these days…
ROHORN says
Hugo, I have no problem with the concept at all -just with some of the truly stupid comments.
Scott says
Didn’t Paul, The Kneeslider, ask everyone to stop nit pickin’ at new designs and try to pick out positives ….. ?
hoyt says
http://www.youtube.com/watch?v=RXwMHLU1z1c
The V-Roehr bike sounds great with the supercharger.
Apparently, the supercharger is an impressive design that includes a bypass valve that allows the motor to operate in its naturally aspirated way when it is at idle, decelerating, or cruising.
More info. should be available soon. Very interested in reading about the handling. Great job Walter! If Walter can get this done with that engine, then what else is possible?
Not that there is anything wrong with a supercharged, American v-twin put into a sport package.
JohninVT – you have valid concerns, but is the swingarm as short as you say it is? It looks on par with the 1098 swingarm in terms of length. We’d have to see it side-by-side or have actual measurements.
todd says
I don’t care, I’d rather have a healthy SV650 for a few thousand dollars. Probably just as quick, if not more so and more fun to figure out what to do with the tens of thousands of dollars left over in my wallet (hypothetically).
-todd
greer says
anyone else think the vrod motor was shrunken slightly to get the proportions right? looks awful small in there
ROHORN says
Take a set of dividers and compare the distance between the valve covers at either end, and compare that to the wheel diameter. Then do the same to the VROD Muscle. They scale out close enough the same to me.
hoyt says
whatever todd. You continue to miss the point, boringly.
John says
So this guy todd thinks his sv650 is as quick as this concept would be let alone a stock Vrod?Dilusional
JohninVT says
As I said earlier…I think this AND the Roehr are very cool. I was only pointing out the glaringly obvious…that the V-Rod engine is very heavy and that its’ size limits how it can be used in a bike. You don’t need a degree in mechanical engineering to know that a 200lb lump poses some design challenges.
Buell has access to the V-Rod engine. If it made sense to use it in a sportbike don’t you think he would have, rather than spending millions on R&D and tooling for the Helicon?
There are some very, very cool V-Rod specials out there. This is a great looking drawing. I DID take a set of dividers to the drawing…and the bike as drawn would have a wheelbase over 60″.
ROHORN says
JohninVT,
You obviously have NO idea what a lot of other engines weigh. Stick a Sportster engine on a scale some time. I have. Then take a tapemeasure to one. I have. Then explain how people have built even lighter and smaller bikes than the one in the above illustration. Including Buell.
Your obsession over wheelbase and swingarm lengths tells me you read a lot of magazines – and have NO other experience with the subject.
There is a whole lot more to motorcycling than the spec sheet. Ask any experienced rider.
Yes, I do think that the Rotax engine was a better choice than the VROD – for what Buell aims for in a bike.
ROHORN says
While I’m at it, pointing out that this engine is big really makes one a master of the obvious. Duh! Then claiming that, since a GSXR with an X lb engine results in a Y lb bike, then any VROD engine’d bike must weigh Z lbs really proves how little one knows about bikes and design. Anybody with a clue would ask why the GSXR is so damn overweight. Blasphemy and all that, isn’t it!There are reasons why a GSXR1000 isn’t a sub 300 lb bike, but none of then have anything to do with performance or handling (on the street).
Guess which is more likely to highside you, given identical horsepower – a high inertia torquey twin or that high spinning flyweight four? Oh yes – swingarm length has NOTHING to do with highsides – it has everything to do with the loose nut behind the handlebar.
Yes, the GSXR is a very fine machine. I enjoyed mine a lot. But it isn’t mine or everyone else’s definition of the perfect performance street bike or even track day bike. And it isn’t because they are lacking in riding talent, enthusiasm, or desire. Or because they can’t read spec charts.
hoyt says
hold on.
I don’t think anyone was making claims to a “perfect performance streetbike”
There are valid concerns of weight and physical dimensions of the Revolution mill. Buell said it. JohninVT said it. It is obvious. Does this mean it would stop one person from pursuing it? Yes. Did it stop Roehrich from pursuing it? No.
I don’t doubt the weight and physical dimensional challenges of the Revolution engine. But, the weight target may be closer than John is wanting to believe.
The V-Roehr is not a 60-inch wheelbase bike. The drawing above might amount to that wheelbase due to the placement of the rad.
The motorcycle.com article mentioned handling challenges that were later dialed in due to loose steering column bearings.
The one item that all of us would agree on is the need for an American-made performance, sport motorcycle. Roehrich is taking steps towards that goal, whether you like the Revolution engine or not or whether it makes sense or not.
(ironically, the one component that makes the engine performance competitive on the track [super-charger] is not American-made.)
Don’t get me wrong, I still like this bike and applaud the efforts.
JohninVT says
ROHORN…I have no idea why you took anything that I said as a personal affront and felt the need to insult me. I praised the overall aesthetic of the drawings several times. I said it was cool. It would probably even be fast….for a Harley.
I have been riding since 1986. I ride a heavily modified, cafe style ZRX1100 and a 1973 Norton Commando. I’ve owned and/or ridden Jap bikes, Brit bikes, Italian bikes and Harleys. If you think a 60″ wheelbase bike can handle like a sportbike or that swingarm length doesn’t matter with heavily tuned engines, then we’re on different wavelengths….and that is fine. I am not obsessed with wheelbases or swingarm length but for about 70 years, sporting motorcycle wheelbases have hovered near 55 inches. There is a reason for that. If you think a Sportster engine makes a good sportbike platform then we’ll just have to agree to disagree. I have gone to Loudon for the races every single year since 1987. I have ridden every Buell model since they began having test rides at the track and not once have I ridden a Buell that was as fast or handled as well as a 10 year old, 600cc Jap bike. You stick to building choppers and I’ll stick to riding bikes that handle and go fast. I happen to ride them enough to know what I’m talking about and I know what is genuinely fast….not just fast for a Harley or Buell.
This is a very cool looking concept. It would be a fun motorcycle as long as you didn’t mind a 60″ wheelbase bike that weighed 500lbs. In other words it would be a great, American power cruiser in the same vein as the Moto Guzzi Griso.
JohninVT says
…and I never said the Roehr has a 60″ wheelbase. I said THIS concept would as it’s drawn. I do not believe Roehr’s weight claims. My reason for bringing up the GSX-R engine weight was to show a comparison of two chassis with similar spec. equipment(forks, frame, shocks, wheels) but different engines and how one weighed A LOT more than the other(more than 70lbs) yet both manufacturer’s claimed similar dry weights. That’s all I was trying to point out. Let me say one more time, I think the Roehr is a neat bike but that doesn’t mean I believe what they say it weighs. Nor do I believe this concept could be built as drawn without it weighing close to 500lbs and having a 60″ wheelbase. That isn’t damning it in any way but that doesn’t mean it would be a very sporting ride either.
todd says
What don’t I get? How many SV650’s are sold compared to VRod sport bikes or even Buells? How many SV’s are used for track/race bikes vs custom VRods or Buells? They all don’t get it either?
I don’t own a SV but I’ve ridden one and I’ve ridden a Buell. Sure the Buell (with nearly twice the engine) felt like it had some more power but it didn’t feel as quick and nimble as the SV and you can buy SV’s for dirt cheap. Sounds like a great deal to me.
If all I cared about out of a bike was what country the company calls its home then I’d buy a Buell / Harley / Victory / VRohr, etc… If I care for value, quality, and performance for what little money I have when looking for a V twin then my money would be on a SV650 (though vanity might make me choose a Hawk GT).
-todd
hoyt says
Todd: “What don’t I get? How many SV650’s are sold compared to VRod sport bikes or even Buells? How many SV’s are used for track/race bikes vs custom VRods or Buells? They all don’t get it either?”
How many times do you interject ideas about small displacement bikes or less expensive bikes on posts that are clearly about project bikes that have nothing to do with the SVs of the world?
The special depicted in the drawing/photoshop above would not be cheap to build. The fabricator &/or owner knows that going into it. Why bring up SVs? If they wanted to build a special with an SV, then their would be a separate post covering the topic.
Even then, depending on the goal, an SV special can run a hefty cost too.
ROHORN says
JohninVT
You obviously have no idea what the wheelbases are on the latest generation of MotoGP bikes. They aren’t 55″.
But funny you mention that number. My last H-D powered sportbike (that I built) had a 55″ wheelbase and weighed 365 lbs on the road. The scale didn’t lie. How’d that happen? Doesn’t sound like a chopper to me. Oh yes – the bike, minus the engine, weighed 180 lbs. You can do math, right? That’s a 4 speed Evo Sportster engine, by the way.
ZRX? Nice bike. Weighed or measured one of those lately? Now there’s a porker. I looked at one several times (along with the SV650 – imagine that) before I bought my last Buell. My Buell was a LOT lighter.
Not that I’m going to buy or build anything like the BuellRod anyway – nobody’s opinion about it conflicts with any personal interests of mine.
But thanks for sharing your point of view. It makes building “impossible” bikes that much more fun.
hoyt says
slightly change of topic…
Any fluid/flow engineers want to weigh in on: “location of radiator”
I’ve heard it mentioned before that putting the radiator under the tailsection is possible. (a comment made here: http://thekneeslider.com/archives/2007/10/08/when-will-honda-produce-the-nas/)
If it is possible why has only one OEM tried it recently (Benelli)?
There are challenges with this location. However, there are advantages to be had to be realized with some clever design and new thought.
The above concept would be very cool (no pun intended) if the rad could be reliably used under the tailsection.
I’ve seen a radiator put underneath. So, what about putting lightweight c-f exhaust canisters on either side of the rear wheel and put the rad underneath? Racing rules would probably have a problem with this, but what about for the street?
hoyt says
to be clear:
put the radiator under the engine and lightweight carbon fiber exhausts in the traditional location.
A v8 Ford motorcycle had the radiator underneath its engine. That is not apples to apples, but if airflow can be cleverly maintained reliably, this would put a lot of weight lower than mounting the radiator in the front or 2 on either side.
todd says
hoyt, why do you care so much about what I say? If you don’t like SV650’s for all their merit and value just because they 1) are Japanese, and 2) can do what other bikes costing many times more having more power can do just as well then who cares what you think either?
I don’t quite care for the typical American big SUV bigger is better, bike bike, more power, super size me thing. I don’t know many (any?) people who can get the most out of the bike they own or the one they just traded up from. I routinely pull way ahead of other sport bike riders on my GB500 or R75/5 on group rides. That tells me power doesn’t mean much on a bike and doesn’t make it any faster.
I like the BuellRod. I like that someone spent the time to draw it up and consider building it. I like that there are creative people and I like that there are great places like The Kneeslider to post ideas. However, as a retail motorcycle I would not be interested in the BuellRod. I could not afford one and it could be much lighter and handle much better (i.e. be a quicker motorcycle) if it didn’t burden itself with such a large, powerful engine. I don’t go drag racing, that’s for cars. 95 percent of my leisure riding is through curvy mountain roads and 90% of my commuting riding is done maintaining the speed limit 😉 That’s why I, and a great number of riders, like smaller capacity motorcycles; that and they’re less expensive.
Now where are all the topics on sporty lightweight motorcycles for a reasonable price that I would be allowed to comment on?
-todd
hoyt says
Todd –
Look at your original post:
“I don’t care, I’d rather have a healthy SV650 for a few thousand dollars.”
Big deal.
There are loads of people on this site, including me, that like small, lightweight bikes too.
You missed the point again. This post is about the VRod special above, not an SV or Hawk 650
Luca Bar says
As some of you can remember after 43 posts I’m the guy who did the rendering.
First of all, thank you all for the interest on my work.
Answering to some of the post you wrote I have to remember that this is just a rendering (2D Photoshop) so I didn’t really care of nothing else than style. I lost most of the lime doing the “pearl white color”.
In any case my intent was to give an idea of how it could be a Buell with a VRod engine, because I belive that Buell riders needs an HD heart; just my opinion.
Bye Luca
JohninVT says
ROHORN….a 1955 BSA Goldstar and a 2008 Honda CBR1000RR both have a wheelbase within a half inch of each other. It’s not a coincidence that the vast majority of sportbikes for the last 50 years have 55 inch wheelbases. Call me obsessive if you like…but it’s a fact.
I do know what the wheelbases are running in MotoGP but I wouldn’t bring that into this conversation any more than I would compare Formula One cars to road going sports cars. It’s not relevant. We’re discussing sportbikes and what IS relevant is that building a V-Rod powered SPORTBIKE is a very difficult proposition because the engine is so big. You can change the subject, you can insult me, you can brag about building a “sportbike” with an antique 4 speed that has the same performance as my 35 year old Commando or a nicely tuned Honda 350…but that doesn’t change the facts. By the way, I don’t believe Roehr’s weight numbers and I definitely don’t believe you when you say you built a road legal, Sportster powered bike with a wet weight of 365lbs. Unless by “on the road” you meant you tossed the engine in a wheelbarrow and pushed it around? There is “impossible” and then there are plain old fairy tales. You’re telling the latter. Not that it has ANYTHING to do with discussing the V-Rod’s usefulness as a sportbike platform.
JohninVT says
Luca,
Your drawing is terrific and obviously has spurred great debate. As a power cruiser like the Moto Guzzi Griso, this would be a great concept. Thanks for sharing.
ROHORN says
It’s cute when consumers claim they know somethign about the subject.
Nicolas says
yes, more fight, again, c’mon guys, more trashing !
kneeslider says
Everyone, … relax! This is a design by a student, done in Photoshop as a styling exercise, as he himself points out above. This intense scrutiny is unnecessary. This isn’t an engineering drawing ready for production.
If you want to comment, think “friendly bench racing” not “political argument.” It’s easy and far more enjoyable.
hoyt says
Bob – I don’t understand the animosity towards JohninVT.
short swingarms can be problematic
long swingarms are used MotoGP due to insane hp. There’s also not a lot of hairpin, narrow turns on many of the tracks so a long wheelbase beyond 55-56 inches does not impact GP bikes as it would on WSB bikes that are sold to consumers.
we all agree the Revo motor is huge and heavy.
I think we all agree the concept above and the VRoehr is cool, for what they are, but disagree what we each would do given a clean sheet.
ROHORN says
Doug,
I would love to know where I can get someone to build a bulletproof 100hp CB350 engine. Oh yes – an old 4 speed Evo Sportster engine has the same tuning potential as a new one. The older ones weigh a bit less. But Mr.”You live in Fairytale land” or whatever his problem is/are wouldn’t know that.
Every year, Supersport new model intros show the same changes – one of which is x mm longer swingarm – whatever you see in GP, you’ll end up seeing in Supersport. Take the new firing order in the R1 (so it emulates a V4 or something like that), traction control, etc..
Back to swingarms – the length is nowhere near as important as the angle of attack (to borrow an aero term), its relative position to the output sprocket, and the spring rate. The only difference length makes is that it has a smaller angle change over any given length of travel than a shorter one. That allows a lower spring rate for better tracking over bumps with the power on, rather than relying strictly on spring rate to keep the swingarm angle from going out of its optimal range.
The above bike doesn’t have GP style output, so there’s no need for GP long swingarm. Yet he then claims that GP wheelbases are irrelevant or some such thing. Hey, is GP design important or not?
Like it says above, it is someone else’s design concept. Actually building something unfashionable and having someone walk up to you and claim that your bike won’t work, nevermind you just rode it there, this reminds me of that….
hoyt says
I disagree with both of you to a point….
JohninVT:
“If you added up all the component weights you’d be well over the 425lbs dry weight they list.”
and
“The Roehr has a super short swingarm to get a 56″ wheelbase.”
and
“It’s nice to dream but just because a V-Rod engine has more power than a typical HD doesn’t mean it’s any more appropriate to build a sportbike with”
There is little information to go on besides the Roehr website and the article below. The article states the dry weight = 432 lbs.
It looks like Walter pulled it off with the stellar materials and components. The supercharger is 6.4 lbs. Not bad. Remember John, he is building a streetbike, not only a racebike. The Aprilia website claims 416 lbs. for the RSV1000
“Anymore appropriate to build a sportbike” — ? This is what probably set off Bob, but I don’t want to speak for him.
“Appropriate” is highly subjective, especially when considering a streetbike. (and then add on top of that one that is niche-built).
I consider my V11 Sport Guzzi an appropriate sportbike. It weighs more than the VRoehr and has 2 valves per jug actuated by pushrods. The R6, R1, YZ750, Speed Triples, etc. that I have ridden through mountain roads together would agree…even factoring in the subjective skill level of their operators.
The Buell Firebolt is still one of my all time street sportbikes and it similar attributes on paper. Nonetheless, it makes an appropriate sportbike.
————————-
ROHORN:
“Your obsession over wheelbase and swingarm lengths tells me you read a lot of magazines – and have NO other experience with the subject”
“It’s cute when consumers claim they know somethign about the subject.”
While I agree with you on spec-sheet recitals and the hype of the supersport product marketing strategies, I think you jumped to conclusions about John. In addition, while not everyone has build experience, they maybe observant enough to know many manufacturers from all parts of the world pay smart and talented engineers a lot of money. Those engineers generally arrive at a comparable geometry of a sport motorcycle. This doesn’t mean we’ve reached thy holy grail, yet, either. But, with the technology and material science available, it is a safe bet.
Do you agree that there is a ballpark (infield) geometry to strive for when building a street, sportbike?….
not much more than 450 lbs wet
not much more than 57 inch wheelbase
not much more rake than 24.5 degrees
etc.
This is not to say bikes like the new XR1200 wouldn’t be sporty on public roads. It also doesn’t mean there aren’t other ways to re-think the general principles entirely.
Signed –
“Jim Lehrer”
http://www.motorcycle.com/manufacturer/roehr-motorcycles-1250sc-review-86824.html
p.s. the Vyrus (tesi-style front-end) nearly has its radiators underneath the engine.
Looking at the length of the muffler in the rendering above, I’d like to see a radiator fit underneath the engine with a small lip curved up on either side.
No one has put efforts into the radiator aside from curving it around the front wheel.
Hugo says
Benelli was the only company who more or less got the underseat radiator working (besides Britten off course but that is a pure racing bike). The SBK version of the Tornado sometimes had one of the air intakes for the radiator covered with duct tape because if cooled too much! I remember that Ian Drysdale tried to put a radiator underneath the seat of his V8 bike but he never got it working properly. In Bradley’s book there is an interesting story about ducted radiators (nothing new there) and I think that Yamaha used that on one of their YZR 500 MotoGP bikes:http://www.mcnews.com.au/Wallpaper/Yamaha/YZR/YZR_OWC1_800p.jpg
Motocsysz uses a similar system, I think (noboby says “I copied their system” 😉
Seems like the Buell CR uses this idea but it looks a little wide. It can probably be narrower but for that you need a narrow (and therefore high) radiator, like for instance the HRC radiator of the RC51: http://img90.imageshack.us/img90/6080/dsc01622rq1.jpg
and you need space because the surrounding surfaces must have an angle of some 12 degrees compared to the radiator (here are some diagrams: http://contrails.free.fr/engine_aerodyn_radia_en.php )
The advantange of ducted radiators is that the cooling is much more efficient meaning you can used smaller radiators, meaning less space/weight, etc.
tylerbrunswick says
hugo since the v-rod is liquid cooled the area on top would be the gas tank.
and sohc since the gas tank would be removeable you would be able to access the valves that way the tank would be removeable like the s1 lightning buells and on the regular v-rods you dont even have to remove the motor to do a valve adjustment