Speak to Ralf Müller at Befaster in Hannover, Germany. He built one of those badasses for a guy in Holland.

 

You may already have seen Britalia Moto's modern take on the the Supermono? if not then take a look here;

The Supermono Strada

Alistair's done a great job on these bikes, pity they're out of my price range.

 

You somewhat beat me to it, but Performance Bikes just did a feature on that bike in the December issue. The article is a lot of fluff, but it's not a bad thing to look at.

I thought the green powdercoating on the case covers and triple clamp to "simulate" Ducati's magnesium finish of the era was a bit of a stretch....

 

This would be sick! I'm a huge Sumo fan. I don't know the answers to your tech questions but if you build this please make a build thread with 1000 pics!

 

Sounds cool! As with any race class, you would need to maximize your CC's for the class to be the easiest power. To me the vertical cyl would have to go. THat buys you a TON of space to lower the tank and make a huge airbox. If you half the power, you may want to half the gear widths all over so you can cut some more weight. Good luck! sounds cool!

 

To me the vertical cyl would have to go. THat buys you a TON of space to lower the tank and make a huge airbox.

Presumably with the original, Ducati had the choice of which cylinder to lose and chose this route - must have been for a good reason.

If you need to shorten the wheelbase you could always angle the engine back further?

 

You may also want check out the superbike forum and a guy called felkinsr.

 

rotating the motor back might hurt the oiling tho?

 

surely if all this fabbing was to happen, a revised oil pickup would be part of it?

 

I was thinking gearbox flooding, but yeah you would need a deep sump and redo the pickup. I would think that given the handling advantage to a Duc, you get rid of the vert cyl and get a huge airbox in there. do a LOT of lightening in the gears, chain, cases, etc. and go as big as you can on the remaining piston. Man sounds fun just thinking about it!

 

I would think you're really going to have to cut weight or get a new frame and of course wheels. Have you looked at a Rotax motor and maybe a monster based frame?

 

Rotax engine.....yeah I have considered the Rotax 650 and of course there are reasons for it being the main weapon of choice for many riders in the class. However there are definately limits as to how much power it can make. Team Pami (Team-Pami.de) are claiming that they can build a 90 HP (no mention of crank or RW HP) 650/725cc Rotax. Swedish teams however seem to agree that as you go above 70 RWHP on the rotax, the reliability totally dissapears and you would be talking multiple rbuild during a season. Now Kaemna (Ducati Aprilia Kmna - Overview) claims that they are hoping for close to 100 RWHP with their Demon single concept.

Also, the idea of replicating the dummy piston of the Supermono is just to interesting to leave alone

JT

 

The real advantage of dropping the verticle cyl is lowering the fuel to the heart of the bike to drop the overall center of gravity dramatically. I would recommend use of the tank area as the airbox. Air up high does not weight anything, generating less swing weight. Without the vertical cyl you can also look at mounting the shock toward the front and possibly lower as well. Getting more of the bikes weight over the front tire is important to a race bikes handling. I agree with all the internal changes mentioned above the gearbox is designed for the big hp and would be very overbuilt for single. Consider a total loss style system to dump the rotating mass of the charging system. Must go with a lithium style battery as well. Reduce the exhuast system to an underengine design with a carbon muffler under the footpeg. Best Wishes Please post pics. Brad.

 

I totally agree with everything you write and my prelim plans are very much along those lines. Definitely going with a total loss system. I am however still entertaining the idea that centralizing the mass around the CoG, achieving a good weight ratio (say 48rear/52front (seen those numbers before?)) AND having good chassis geometry may be obtained by keeping the V cyl. When I say good chassis geometry for this build I mean cutting the wheelbase by around 4" and at the same time run a longer swing arm, say 1-2" longer. What I'm at is moving the fuel tank to where the H cyl used to be, except 4" shorter and way taller. And as you suggest the airbox would be where the tank usually is.

What do you think of such a solution?

JT

 

Don't forget the v-twin engine is a synergistic device. The power stroke from one cylinder keeps the crank spinning to keep the revs/torque up until the other cylinder fires. Cutting one cylinder from the equation will not net 1/2 the power from the original engine.

 

This is interesting. Not sure I get the full picture though. Are you certain this is the case? I mean I'm not sure I follow the logic completely. Are you saying that a 4 would net more than the double of a comparable twin too? Also, if it had to do with keeping the flywheel in motion, then one could add a massive flywheel and up the HP?

When hearing about the I4 advantage over the L2 given the same displacement I always hear that the larger area available for valves is what makes the I4 make more power per displacement. I never hear anything about smoother flywheel action making more powerI really can't see why a single wouldn't make 1/2 the power of a twin.

Care to expand?

JT

 

My point is you have to move the weight of two connecting rods and a flywheel/crank that was previously powered by two piston power strokes. You wouldn't need a heavier flywheel considering your supermono design already has a bigger flywheel/crank than one cylinder needs. I think you're going to have an excellent torque number. If your motor runs smoother maybe you can make up the weight/frictional loss with a higher rpm.

The Supermono has 75HP from the factory but a 1098 has 160HP. Maybe it's 20 years of technology that gives the 1098 more than double the HP of the 549cc Supermono?
I don't think I can compute the frictional loss of your supermono engine. Maybe you can run your engine on a dyno with one sparkplug pulled out and unplug the injector?
I'm certainly hoping you can do this though. Maybe the torque alone will give you the power you need.