Bike vs Car fuel economy - help please

Originally Posted by ThEGr33k

Mostly down to the front wheel I think. If you covered that in Fairing its be much more efficient.

Covering in the front as in “dustbin fairing” would make a difference; seem to remember seeing a drag coef. of 0.4 for a bike with one.
I did a comparison of car and bike drag figures a while back and a standard bike with its small frontal area and poor drag coefficient (Cd) worked out to have a ball park figure of up to three quarters the total drag of a car.

The race regulations are very restrictive on the amount streamlining that can be used and road bikes are styled on race bikes (everyone wants a bike like Rossi’s etc.) so we are not likely to see any improvements as far as aerodynamics go unless this bike comes into production.
http://www.ecossespirit.com/

Bike engines seem to be designed to produced power at the expense fuel economy, except India Enfield who have now got a lean burn 500 that does something like 84mpg but has only got 27 gee gee's.

Originally Posted by OldBoy

Covering in the front as in “dustbin fairing” would make a difference; seem to remember seeing a drag coef. of 0.4 for a bike with one.

indeed they banned the dustbin fairings back in the day because the bikes were too fast (the handling was poor too because of it.) something like a 250 with about 50 BHP doing 160MPH is what I remember hearing!!! Imagine what a Gixxer with dustbin faring could do!?!?!?!?? WOW

2005 R model.

The engine just stopped on me last wednesday. EFI light came up and I had a blown fuse. Put the replacement fuse in and that blew straight away too. Found the problem at the weekend - I can still hardly believe it killed the bike...












... it was the speedo pickup

Must have been a short internally, blew the fuse which took out everything on that circuit, which included the fuel pump.

my 02 R6 is loads better on fuel than my 1.1 saxo of cource that changes a bit if i rag the R6 and same with the saxo... how ever the car is better on motorways....

[yorkie_chris]

Wasn't the other reason for banning dustbin fairings the likelihood of being blown straight off the track in any crosswind?

Originally Posted by ThEGr33k

indeed they banned the dustbin fairings back in the day because the bikes were too fast (the handling was poor too because of it.) something like a 250 with about 50 BHP doing 160MPH is what I remember hearing!!! Imagine what a Gixxer with dustbin faring could do!?!?!?!?? WOW

You may of been thinking of the Modial 250, 138mph on 29hp and the Guzzi V8
http://en.wikipedia.org/wiki/Moto_Gu...Prix_500_cc_V8

172mph on SV650 hp!

More details on aerodynamics here, have a look at the Dreamliner mpg figures.
http://www.tonyfoale.com/Articles/Aerodynamics/AERO.htm

Originally Posted by OldBoy

You may of been thinking of the Modial 250, 138mph on 29hp and the Guzzi V8
http://en.wikipedia.org/wiki/Moto_Gu...Prix_500_cc_V8

Ahhh yes. Wasnt sure if it was 140 or 160, long time since I read about it... so I thought id go for the more impressive .

Piece of kit indeed. V8 too WOOT. listen that rev, YES please!

Originally Posted by yorkie_chris

Wasn't the other reason for banning dustbin fairings the likelihood of being blown straight off the track in any crosswind?

Yes, I think that was one of the fears, the streamlining shape has to give the centre of air pressure behind the centre of gravity for stability. Also not alot of air for the drum brakes of the time at the end of the straights.