Posted: Thu Sep 05, 2013 11:12 pm
On listening to the banter `interesting` as my R1100RS will only average 33 mpg on a buzzing around situation! `Ride up north, A1 route, 38/40 mpg averaging 75/85 mph.
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cros wrote:On listening to the banter `interesting` as my R1100RS will only average 33 mpg on a buzzing around situation! `Ride up north, A1 route, 38/40 mpg averaging 75/85 mph.
Gromit wrote:bikesnbones wrote:Don't forget the effect of aerodynmaics.
Any bike, no matter how well faired, is an aerodynamic nightmare.
Stick a rider on board, and the problem is doubled.
Of course this only excuses low mpg at constant motorway speeds.
Not in town.
Exactly.
I had this discussion with a non-biking friend some time ago, who was asking what the performance of my Blackbird was like against modern supercars. I stated that on acceleration, it would take a very serious car to even get anywhere close to it from a *rolling start up to 140mph or so. I then explained its power/weight ratio and the peformance potential hits home (ie 145-150bhp at the wheel pushing 220kg or so) ie 650+bhp/tonne.
However, its top speed is nothing like what one would imagine it should be, bearing in mind the power to weight. There are many cars going a fair bit quicker, on a much lower power-weight.
Said friend was slightly baffled at this but it's simple - as BnB said, bikes' aerodynamics are pretty dreadful. Above 100mph, a huge amount of the engine's oomph is taken just to battle against the drag of the air. Cars win back very convincingly.
*I say a rolling start as cars are a darn sight easier to get off the line with their traction/launch controls etc.
conkerman wrote:From awful to shit I imagine.
Don't think they are ever published anywhere.
conkerman wrote:From awful to shit I imagine.
Don't think they are ever published anywhere.
Gromit wrote:conkerman wrote:From awful to shit I imagine.
Don't think they are ever published anywhere.
Indeed - and there are so many variables (ie size of rider, clothing etc) that it'd be hard to evaluate.
Gromit wrote:Indeed - and there are so many variables (ie size of rider, clothing etc) that it'd be hard to evaluate.
McBoxer wrote:Gromit wrote:Indeed - and there are so many variables (ie size of rider, clothing etc) that it'd be hard to evaluate.
+1 on that. The only thing the manufacturers could measure with any degree of consistency is the bike without rider, and those figures would be meaningless as soon as a fat pork pie eating Scotsman got within 6 feet of it
Corvus wrote:McBoxer wrote:Gromit wrote:Indeed - and there are so many variables (ie size of rider, clothing etc) that it'd be hard to evaluate.
+1 on that. The only thing the manufacturers could measure with any degree of consistency is the bike without rider, and those figures would be meaningless as soon as a fat pork pie eating Scotsman got within 6 feet of it
True, to a point. One could always design the bike with bodywork to cater for the worst case. To a point.
I personally hate fairings, but that's not the point here.
Or have industry standards. eg: 6 foot rider weighing 13 stones sat with knees on tank, etc. or whatever other figures you like.
McBoxer wrote:Corvus wrote:McBoxer wrote:Gromit wrote:Indeed - and there are so many variables (ie size of rider, clothing etc) that it'd be hard to evaluate.
+1 on that. The only thing the manufacturers could measure with any degree of consistency is the bike without rider, and those figures would be meaningless as soon as a fat pork pie eating Scotsman got within 6 feet of it
True, to a point. One could always design the bike with bodywork to cater for the worst case. To a point.
I personally hate fairings, but that's not the point here.
Or have industry standards. eg: 6 foot rider weighing 13 stones sat with knees on tank, etc. or whatever other figures you like.
Good points. I guess I was thinking more of naked bikes - and it would take bodywork larger than Texas to fair in some riders (myself included!), but the industry standard could work. maybe some kind of crash test dummy?