Project 100 (custom enclosed Honda C90 targets 100 mph vmax and 100 km/L FE)

[NachtRitter]

For reference: Obama's limo getting high-centered:

http://www.youtube.com/watch?v=tlqsYCUluSA

[godscountry]

they have tires that have low rolling resistance[economy] but offer all the grip needed,like the michelins on the new hybrid race Porsche

[visionary]

http://ecomodder.com/forum/showthrea...rch-26249.html

I have just posted a new thread in the aerodynamics forum, which I hope will provide support information for this thread and bring in a wider range of knowledgeable opinions from members with specific aerodynamic knowledge.
My hope is that it will address issues about knowledge of aerodynamic performance of full-bodied motorcycles in general, rather than be specific to my project.
It follows from my comments in post #165

Originally Posted by visionary

Interim Update

I have been following other threads and preparing a detailed post on my aerodynamic viewpoint, which will “put the cat among the pigeons” but that can wait a bit longer.

At present I’m well advanced with my bodyshell construction, but of course I still don’t know how it will perform at speed in windy conditions. Lets hope the new thread will help me avoid expensive mistakes.

[metromizer]

Originally Posted by TedV

"High centering" is usually a term used for semi trailers that are low or a car that has been lowered to the extreme. going over raised railroad tracks or speed bump, the center of the trailer or vehicle contacts the pavement and the wheels no longer make as good of contact with the pavement. When the tires loose contact with pavement they loose traction. If you are moving when this happens you loose some control of the vehicle.

I think he is concerned with front end compresing under hard braking and the bottom of the bike hitting the ground. Most regular bikes will do a stoppie or endo, lifting the rear wheel if the front tire doesn't lock up and slide first.

That's right. My concern is if the center portion of the relatively long wheelbased bike accidentally 'bottoms out' whilst making a turn, while cresting a driveway and slightly leaned over for instance. I could imagine the bike's chassis center dragging, the suspension unloading, causing the back end to come 'round so to speak.

[Grant-53]

Most motorcycles have 4-5 inches of ground clearance with a wheelbase of 50-55 inches. My Geo Prism/Corolla has 9 inches of clearance. My bicycle has 3 inches clearance with the pedal at the bottom. If the ground clearance is 10% of the wheelbase I would be satisfied for street use. Suspension travel and spring rate are critical. With a lower center of mass you would have less weight transfer under braking. I hope the motorcycle aerodynamic thread is helpful.

[visionary]

My thoughts about high-centering

Although I wasn’t familiar with the term “high-centering”, which we call ”beaching” in the UK (obviously less descriptive than the US term), I have given some consideration to the problem. Although significantly longer wheelbase than traditional motorcycles, the vehicle still compares well by car standards. In fact the ground clearance (currently 150mm) could go down to 100mm and still compare well with a traditional sports car (MR2/350Z). So I don’t see this as a major problem.

Of course when banked over, all motorcycles risk contact with the ground at extreme angles and this will be no different. I won’t achieve lean angles like a sports bike but I will do better than cruisers. Some of the earlier pictures and video do not show this clearly but on my next test ride I will make a point of showing the ground proximity during cornering. I have a GoPro camera with which to get better images on the next video.

I have made another comparison image which shows the Project 100 vehicle against the Peraves Monotracer and the Suprine Exodus.



Although this image is a bit busy, it clearly shows my “Goldilocks” design – not too short, not too long. I hope this in-the-middle philosophy will work out for me.

[visionary]

Originally Posted by Grant-53

I hope the motorcycle aerodynamic thread is helpful.

The aerodynamics thread has not lived up to my expectation, but I want to thank you and all others who contributed.
My aim was to enlist some of the bright minds from the aerodynamics forum who would otherwise not be focussed on motorcycle issues. In practice almost all input was from our traditional group of motorcycle enthusiasts and so this added nothing that has not been covered in the "Motorcycle Aerodynamics - A slippery and windy slope" thread.

I had hoped more research material would surface, but it seems there's a lack of good info out there. I did find some interesting stuff myself, but not much new, and here is a link to an entertaining youtube video

Wilhelm Herz auf NSU Delphin III - YouTube

On a more positive note, I had a very interesting day yesterday when I went to Mallory Park racetrack for the "Festival Of a Thousand Bikes". Among other luminaries from the FF bike world, I had enjoyable conversations with Paul Blezard (PaulBlez who has posted earlier in this thread), Colin Russell (the driving force behind the monoliner project www.mono-liner.co.uk) and Andy Tribble (owner of a Peraves Ecomobile).

Andy was nice enough to let me sit in his ecomobile and give me an unbiased opinion of ecomobile ownership, and riding dynamics - very enlightening!

Meanwhile my bodywork is making slow but steady progress, I just have to iron out a few wrinkles in the opening/closing mechanism and I will post a little video of the entry procedure and ergonomics - then its off for another test.

[Frank Lee]

Andy was nice enough to let me sit in his ecomobile and give me an unbiased opinion of ecomobile ownership, and riding dynamics - very enlightening!

What did he say? Inquiring minds need to know!

[visionary]

Hi Frank, well we chatted for about an hour in total and Andy is a very open character so there was a great deal to absorb, but I can relay some simple elements of the conversation.

What struck me most was the issue of steering control. I don't know about you, but I had imagined that all the hype about training before being "qualified" to control the machine was just that - "hype". I would have been keen to give-it-a-go without any reservations before trying it for size. However, once seated in it I realised what an intimidating machine it is. Andy explains that transition between "car steering" with the wheels down and counter-steering with them up takes practice to master, and its a skill that needs to be kept up-to-date. Some owners who don't use their machines regularly can loose their confidence and require re-training.

There are also some unsettling aerodynamic effects which really do make it feel like flying, but overall while it can be mastered, the vehicle is not naturally intuitive to control.

The ergonomics are poor and take familiarity to get comfortable with, Andy explained some idiosyncrasies which he has become accustomed to but would have preferred good solutions, like wheel-down speed control and screen demisting can be a problem as it wasn't fully solved. Andy's eco is an early example and I suspect that the new Monotracer version must be better in this respect.

In summary, while he acknowledges the great achievements of this vehicle he feels that it does not represent a mass-market solution to the transport niche and it probably will remain a rare, expensive, milestone.

[renault_megane_dci]

Thought so ...