What uses more fuel?

[craigs23]

Holding a throttle enough to hit maximum revs,

or holding full throttle at maximum revs?

Or is it the same because road/engine speed is identical anyway?

Or am I just being a noob?

[evoboy]

More you twist the grip on the right, the more fuel you use...

Sounds like your just complicating things

[Pete.]

Fuel consumption is more connected to load than revs. You can hit max revs with very little load and almost no throttle and not use much fuel, but if you want to hit max revs at full load you'll need to be in top gear (supposing yuor engine has enough power to pull full revs in top) - and this is when your consumption will be highest.
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a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good

[Kickstart]

Hi

If you mean holding it wide open and accelerating or holding it wide open at the full speed, I would suspect holding it at full speed would use more.

However I suspect it would also greatly depend on the fuel system. Something with accelerator pumps would have squirted in a large lump of extra fuel as you wound it onto full throttle. Something with CV carbs would effectively not give you full throttle even if you had opened the throttle fully.

All the best

Keith
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Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

[craigs23]

Interesting. I was just musing the idea when stuck behind a couple of friends on a rideout. Mostly down to whether I should stay in a high gear and use less throttle, or a lower one that might make the engine work a little more.

Not that I'm concerned about fuel consumption too much - the DRZ's returning a surprisingly good rate. But I did start day dreaming about the hypothetical scenario above.... like you do.....

[Kickstart]

Hi

Think all you do is try it out.

I tend to use lower gear than most people which you would expect to increase fuel used. But strangely I seem to get better fuel consumption than many.

All the best

Keith
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Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

[MarJay]

You should drive a BMW 3 series with an analog fuel consumption gauge. It really teaches you about what affects fuel consumption.

If I'm in 5th at 80mph, and I want to accelerate, If I put my foot down hard the fuel consumption gauge drops but returns slowly as I return to constant throttle. If I change down and do the same the needle is buried in the low end of fuel consumption, but returns to normal much more quickly when I change gear.

The closest relationship between all of the factors and the reading on the gauge is how far down I've got my right foot!
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British beauty: Triumph Street Triple R; Loony stroker: KR1S; Track fun: GSXR750 L1; Commuter Missile: GSX-S1000F; Cheap project: CBR900RR FireBlade
Remember kids, bikes aren't like lego. You can't easily take a part from one bike and then fit it to another.

[Walloper]

More load more fuel consumption no matter how you slice or dice it.

Think of horse walking around a field all day or galloping along a turnpike tied onto a stage coach.

More work more hay.

That's why we call work done horsepower...

That question was Nay.... bother for me..

And full-load is full-load no matter what gear you are in.

1st 2nd or Top hat & tails
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W-ireless A-rtificial L-ifeform L-imited to O-bservation P-eacekeeping and E-fficient R-epair

[Alexio]

What if I'm cruising at a sensible 5000RPM (for my bike at least) and without changing the amount of throttle hit a very steep steep hill? Suddenly there's a huge load on the engine and it can only just about manage it (it's sounding like it wants to go down gear).

Would the extra load increase fuel consumption? Of course I think it will. And the wind resistance is basically the main "load" on the engine the fast you go. So will a lower gear with slightly higher revs use less fuel sometimes because there is less load on the engine to constantly maintain those revs? Probably...

There are no exact answers... I just enjoy asking questions
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will never give up his CG. I look at my fuel gauge more as a progress bar than a fuel gauge.
G: With my GSXR I do often effectively use it as a scooter with a clutch in town.
ms51ves3: why does it need 500 miles? Are you teaching it how to be a piston?

[Kickstart]

Hi

If you are cruising at a constant speed and hit a hill then you will slow down unless you open the throttle more (maybe only a small amount). The load will even itself out (ie, you will slow down enough that the reduced wind resistance will make up for the load of going up hill).

While a lower gear might well mean more revs, the actual revs take very little power compared to moving the bike. After that you are probably in to how accurately the fueling is set up for particular revs. An engine is meant to be at its most efficient at the revs of peak torque, which might well be at revs that match using a lower gear.

All the best

Keith
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Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

[craigs23]

On a similar note...I had another thought today.

My Superfour, which I was commuting on is geared higher than standard. It will pull 70mph in top at 6,500rpm or so, rather than the standard's 7,000rpm.

It returns over 55mpg on average...but I wondered...would this be any different if the gearing was standard - I tend to use a little more throttle than I thought I would, especially on a incline and being lazy to change down. 55mpg sounds about right for the 400....would the differences be pretty much negligible anyway?

[Kickstart]

Hi

Again maybe. Keeping things simple it should but too much down to the individual bike.

All the best

Keith
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Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing