Minimizing drag at 140mph+

[Michael Moore]

Originally Posted by freethink

Not sure what you mean by that. I don't think you'll find much of any gimmicks on GP bikes..

Maybe not so much now as in the past, but motorcycle road racing has seen a lot , if not a preponderance at times, of bikes out on the track with pretty suspect bodywork. Remember, international and national level racing is a promotional thing for the mfgrs, and they have a lot invested in keeping the racers looking like the street bikes in the showroom (and vice versa).

Some teams have clearly spent time in wind tunnels and paid attention to what they learned. Others, not so much.

CoClimber, are you in a production class where you have to retain the stock fuel tank and other body parts? If not, then ditch the tank and make a small 1 quart tank that lets you lower your upper body as much as you can.

cheers,
Michael

[Frank]

Originally Posted by Michael Moore

BTW while Vol 1 & 2 are out of print (John will reprint when Vol 3 is done)

That's great news, those books seem pretty hard to come by. The Can-Am work is classic.

I also remember reading about acceleration tests of bikes with and without cumbersome, heavy dustbin fairings and even with the extra weight, the dustbin bike accelerated quicker. This is of interest to me as I'm also a drag racer but haven't taken the time yet to work on aero, but there's definitely potential!

[jkv357]

Originally Posted by freethink

"Chances are, if they ARE using funky bodywork, it is probably just a gimmick too."

-Not sure what you mean by that. I don't think you'll find much of any gimmicks on GP bikes.

"over the last 45+ years, I keep seeing road racers at high levels of competition using really funky bodywork."

-Neither of the current model MotoPG, or Moto2 bikes have those 'funky' channels down the sides of the front fairing that the R6 has.

I would say the "wing thing" in MotoGP would qualify as "funky bodywork"and possibly a gimmick. It did seem to help Ducati, but wasn't adopted by Honda or Yamaha after testing. It's banned next year.

The panels on the side of the older R6 were referred to as "barge boards" and came from F1 "aero-think" at the time. Didn't catch on.

[CoClimber]

Michael Moore, that photo was taken while I was doing clutch tuning. It wasn't a speed run, otherwise I would have been tucked much lower. Grant, we should get together and compare notes. I am also taking what I learned and am helping to make a high speed ebike.

[gumby79]

Originally Posted by jkv357

I would say the "wing thing" in MotoGP would qualify as "funky bodywork"and possibly a gimmick. It did seem to help Ducati, but wasn't adopted by Honda or Yamaha after testing. It's banned next year.

The panels on the side of the older R6 were referred to as "barge boards" and came from F1 "aero-think" at the time. Didn't catch on.

A simple Google. First result is:

At Assen, MotoGP's Grand Prix Commission announced that aerodynamic winglets will be banned from 2017.

The downforce generated by winglets helps resist the natural tendency of a motorcycle to wheelie under acceleration, which means less use of anti-wheelie electronics and more engine output.

Read more at MotoGP Feature - Why wings were banned in MotoGP

In summary the article stated that 1or more manufacturer didn't want to spend the money in the wind tunnel to develop the technology. So a simple no action, resulting in the technology being ban.
In my opinion this was a simple way to remove a competitive advantage. And a way to save money on there R&D budget.

Ducati Corse general manager Gigi Dall'Igna also suggested that the failure to reach a deal within the MSMA had been motivated by a desire to neutralise Ducati's aerodynamic advantage:

Read more at MotoGP Feature - Why wings were banned in MotoGP

This is an excellent example of a good technological advancement that would have made it to street bikes,but was killed by a desire to not keep up with the Jones's.
Dreem big chisel down to reality.

[Michael Moore]

Frank, I think you are referring to the Royal Enfield Dreamliner which I described here

http://ecomodder.com/forum/showthrea...tml#post277230

In the "Free Speed" article on my webite (in this folder)

Index of /graphics/aero

circa 1975 the author points out how many of the factory F750 fairings had pretty obvious faults. Some factories from the 1950s on have spent time on wind tunnel development (NSU, Guzzi, more recently Derbi, Aprilia) and others seem to just copy or do whatever strikes their fancy. When you get to people racing at the club level then all bets are off on what you'll find. I've seen a number of people on small vintage RR bikes running fairings that leave 3-4" of rider sticking out all the way around. They may as well leave the fairing off and save the weight.

cheers,
Michael

[Frank]

Originally Posted by Michael Moore

Frank, I think you are referring to the Royal Enfield Dreamliner which I described here

http://ecomodder.com/forum/showthrea...tml#post277230

In the "Free Speed" article on my webite (in this folder)

Index of /graphics/aero

circa 1975 the author points out how many of the factory F750 fairings had pretty obvious faults. Some factories from the 1950s on have spent time on wind tunnel development (NSU, Guzzi, more recently Derbi, Aprilia) and others seem to just copy or do whatever strikes their fancy. When you get to people racing at the club level then all bets are off on what you'll find. I've seen a number of people on small vintage RR bikes running fairings that leave 3-4" of rider sticking out all the way around. They may as well leave the fairing off and save the weight.

cheers,
Michael

Michael: I believe that is indeed the bike. Thanks for the links, I'll check them later.

CoClimber: keep us up to date on your ebike plans. I race electric drag and LSR bikes and am always interested in new builds.

p.s.: Jake - sorry 'bout the hijack!

[jkv357]

Originally Posted by gumby79

A simple Google. First result is:

In summary the article stated that 1or more manufacturer didn't want to spend the money in the wind tunnel to develop the technology. So a simple no action, resulting in the technology being ban.

In my opinion this was a simple way to remove a competitive advantage. And a way to save money on there R&D budget.

This is an excellent example of a good technological advancement that would have made it to street bikes,but was killed by a desire to not keep up with the Jones's.
Dreem big chisel down to reality.

Ya, I get what wings were used for, but if Ducati could find them useful I'm sure that The Honda could figure out how to make them work. The fact that Yamaha and HRC tried them and didn't use them consistently says that maybe they weren't all that.

Reducing R&D costs is the main focus of almost all new rules at this point.

I don't think that additional MotoGP wing development would have benefited street bikes very much, but that didn't stop Kawasaki from going nuts with them on the H2R - https://i.ytimg.com/vi/N3QvX24iBiE/maxresdefault.jpg

Kawasaki and Ducati were relying on big power to get all that top speed, because those wings aren't helping (except for reducing the need for more electronic wheelie control when accelerating at speed).

[slime]

I would use Hayabusa bodywork...or at least the front fender..

[slime]

Originally Posted by Michael Moore

Chances are, if they ARE using funky bodywork, it is probably just a gimmick too.

It is surprising how, over the last 45+ years, I keep seeing road racers at high levels of competition using really funky bodywork. The details may be "rocket science" but what is needed as a good starting point has been out in the public arena all that time. I've pointed out to many people that a fairing that leaves 4" of rider hanging out all the way around isn't doing much good, though that usually results in a blank stare in return.

A kind of related anecodote: I used to be the North American distributor for John Bradley's two volume set of "The Racing Motorcycle: a technical guide for constructors" (and John is working on Vol 3). I sold copies to all the major manufacturer US branches and John sold plenty of books to national/international level racers/teams. John mentioned that it wasn't uncommon to stop off at a club race to show the books around and get a "meh, why would I want a book like this, I'm a RACER" response. On the other hand, go to a big national/international race and they were an easy sell.

I remember selling a copy of Vol 1 (the book with the aerodynamics/chassis dynamics stuff) to a bike drag racer, and he couldn't see any reason it would help him so I took the book back and refunded his money. Showing V1 to another drag racer (and a much more successful one) had him saying "wow, I'm so going to use this and cut my times/boost my speed at the strip".

You can lead a racer to the river of knowledge, but you can't make him take a drink from it, especially if he hasn't seen whatever you are offering in the monthly magazines.

BTW while Vol 1 & 2 are out of print (John will reprint when Vol 3 is done) there are a few copies of them that show up on eBay now and then, more so Volume 1 than V2. The page with results from wind tunnel-tested modifications to the Can Am 125/175 LSR bikes is very interesting.

cheers,
Michael

Volume One is on Amazon!