Fuel consumption

[yoda]

interesting, my xt660z does 64mpg day in day out on normal a road riding and commuting, std bike with kev mod, however on the long m/way slog up to scotland with any luggage on its drops to 51mpg, ok its working harder and i'm not very aerodynamic. However my 1200 s/tenere averages about 56 mpg on the same m/way run with luggage on, pretty much the same as my last 1200gs did. a couple of yrs ago i had a w/end run up there, m/way up on the fri eve, saturday all day out and the run to Ardnamurchan l/house and back, then sun m/way all the way home, my w/end ave that i sat and worked out was 61mpg for the 1200. I am not a high speed merchant and i'm quite mechanicly sympathetic the bike is also pretty much std, not re flashed etc.

[garyboy]

a bigger engine bike is pulling a lower gear for the same speed.
the wind profile is almost the same.
also the engine has not really got into its `frenetic` power band where all the revs are, and all the fuel consumption is.
it has a lower down torque, and is not straining.

there is probably a comparison equation thing somewhere?
imagine two bikes going to Scotland .. one a 50 cc that can do 60mph and the other a 1200cc that is also doing 60mph.

there is probably an `ideal` area of power and weight, not power to weight ratio, but, for the real road, and ideal weight to strength to power thing. the bigger the bike and engine the better .. to a point, then it gets too big?

any suggestions as to the perfect bike for this?

[steve the grease]

I would say Davecon is right.

I have been looking at fuelly.com and both of you have beat the average for both bikes by a long way. So you need to get some more data to level out fuelling inconsistencies.

I think 10 tanks will start to give you a better picture. Then when you have that done and established a baseline for each of you on your own bike you would need to go do it all again on each others bikes to run out the different riding styles.

But why is there such a difference I can't say with any authority, but weight will be a big factor, if you have a lot of speed changes. Pity we can't get COG figures for bikes, because it would be interesting to see if the baby Ten has a better aero than the S10. I would have thought the S10 is more streamlined, but maybe not.

In these days of speed cameras I am becoming increasing in the game of getting the best mpg I can.

My current NC750x.
http://www.fuelly.com/motorcycle/honda/ ... nge/319745

My old XT660z.
http://www.fuelly.com/motorcycle/yamaha ... nge/165237

We were not going very fast, 70 MPH on the motorway and not much more than 50 MPH on the minor roads.

Wind resistance doubles between 50 and 70 , remember in the previous post about wind resistance doubling with speed...... well 5x5=25 and 7x7=49 pretty well double. Doubles again between 70 and 100 10x10=100 ( obviously)

[dave h]

miles per gallon is important,
but i prefer smiles per gallon B)

dave.

[wwdph02]

duplicated entry

[wwdph02]

This was the result after a trip up to Arctic Circle and Lofoten Islands. I will say that 3000 miles across Norway were subject to plenty of 80kph/50mph limits but my BMW R1200RS ran well at low revs, high gears better than some sport bikes may like. It does depend on how the engine is tuned as confirmed by a KTM adventure rider, two up and loaded, who could not use high gears and found it hard work running at low speeds with medium revs.

P1000236_2017-03-17.JPG (29.45 KiB) Viewed 2926 times

The 886miles was last day from Denmark back to uk in one hit from 10am to 7am the next day. Rain was so bad across Germany to channel tunnel I just kept going, it did stop before I left the M25 heading to Devon.

[minkyhead]

not sure that can be right

my tenere did around 55mpg on the motorway off road around 40/45mpg and around 60mpg average ....83mpg is more than i get from me crf300 which is around 77mpg ?

i suupose if you ride a billiard table no hills or headwinds and stick to 55mph its possible but real world speeds and off road thats way out

[AlanHolt]

Everyone rides/drives slightly different to each other. Being a former SAFED trainer, little things make a big difference. Generally the lead vehicle will use more fuel as the one following will ease off the gas earlier, brake less and therefor use less fuel. Tyre pressures make a big difference too. Specifically on commercial vehicles, just a 1% drop in tyre pressure can increase fuel consumption by 10%. Factor the above, plus whether one rider opens the throttle progressively compared to the other who winds it fully open straight away, and you will get huge differences in fuel consumption.

[waynecoluk]

A lot of it is down to how you ride as well.
Ride magazine did a comparison last year where they took 3 bikes and tested their range.
The Honda CBF125 did 350 ish miles on a tank, the BMW 1200 GSA did 424 miles on a tank but the biggest surprise was the Kawasaki Versys 650 which did 404 miles on one tank. Obviously these guys were taking it very easily but as it was all motorway miles the CBF struggled because the engine was having to work harder where the Versys and GSA were in their economical "zone" I guess.
Even though both of you did the same journey one of you could have been on and off the throttle more or something like that. I guess there are a lot of variables

[jonny955]

Petrol engines are subject to throttling losses which put extra load on the engine when the throttles are nearly closed because it has to suck air through a strangled inlet.

Contrary to popular belief, running at the lowest possible throttle opening does not always mean using the least fuel. If the engine has to work harder simply just to keep turning, it will use more.

So, enjoy your wide open throttle lunacy and save the planet

Jon