Cycling UK Forum

Dr Yan's fuel duel:

http://www.youtube.com/watch?v=SC9MTWyk2jk

Interesting clip on fuel efficiency.

Looks like the bicycle needs a bit more air in the tyres...

Plus, he chose the most efficient moped and I'm sure you can't call that the most efficient bicycle. Still the results were unsurprising.

1,000cals?
On the flat?
How long did it take him?
How much petrol was in the jar?
1,000cals will get me about 17miles or so on my bike pedalling very hard ........... with HILLS.

Good experiment, but a few facts would be great. However, the difference was so marked, the details are immaterial.
Or are they ...............
Why did the moped and the cyclist not do the same speed?

Mick F wrote:1,000cals?
On the flat?

Why did the moped and the cyclist not do the same speed?

I recon it was all flat around that race track.

And not doing the same speed was my biggest gripe, otherwise interesting!

Mick F wrote:How much petrol was in the jar?

i'd say around 1/2 pint - 250ml





the video is utter tripe.

the moped is the mass it is out of necessity, the cycle because he added the equivalent of engine, gearbox, fuel tank & then the tyres, wheels and brakes to cope with the weight of engine, gearbox, tank etc.....

secondly, the cycle (& it's additions - extra 2 wheels?)) aren't made for aerodynamics, the moped are

thirdly, there's a definite benefit to his health from having the exercise of cycling...none for mopedding

fourthly. some of the calories we consume are sustainable...whilst i'll happily concede that it varies with an individual's diet...petrol utterly isn't sustainable

finally, his cycle's on schwalbe tyres

it'd be even more in the benefit of cycles had he been riding an unencumbered bike.

it's an estimate, but i can ride for many miles on my best bike before i'm tired...that rig he's got there would have me spent in a fraction of the distance.


and that's before we discuss the ecomomics.....my aforementioned best bike is nearly 60 years old, and cost (i think) between £30/3/1 and £39/19/6 . it's needed no insurance, no MOTs, no VEDs, no depreciation.

maybe the speed was calculated in the most efficient range of the engine and gearbox, likewise he was probably cycling at a predetermined speed that they gauged was the most efficient use of his calories.

TBH though he should have trounced it even more, I reckon one of us riding a proper bike (not that monstrosity) could turn a rather large gear on the dead flat for ages.

there's another thing. say you were riding home from work, and met a mate. fancied a few jars. it'd be a no-no on the 'ped. fine on a cycle

Mick F wrote:1,000cals will get me about 17miles or so on my bike pedalling very hard ........... with HILLS.

Difference is that you're a fit cyclist who is used to it. Is that energy expenditure inclusive of you set up for touring or a leisure ride?

hubgear freak is spot-on. The whole piece of work is utter tripe.

My energy comes from food , which can be made from soil and air in a few days; the moped's from oil which might perhaps be made from crops at enormous energy and financial cost( but is not). My bike weighs considerably less than a moped and in the making consumed correspondingly less fuel and money.etc etc

Surely in the first minute this project was considered all these things must have been obvious to the most intellectually challenged schoolboy.
I wonder if the motor industry had anything to do with encouraging this rubbish, or perhaps it is a supplication to that faction:'' here I am , a desperate embryo scientist who will do anything at all for the possibility of money, and I know who has got lots of it.''

Yes, rubbish video. The rear tyre on the cycle is almost flat so very inefficient. Adding weight to the cycle is stupid it means you aren't comparing a moped with a bike. It's like saying an hgv is more efficient than a bike because a 1000 calories will move it a short distance whilst a cyclist burning 1000 calories won't move a bike weighing 38 tons at all.

Unless you are a moped delivery driver then almost all the energy is wasted moving an unnecessary 100kg of metal around...

Alex L wrote:

Mick F wrote:1,000cals will get me about 17miles or so on my bike pedalling very hard ........... with HILLS.

Difference is that you're a fit cyclist who is used to it. Is that energy expenditure inclusive of you set up for touring or a leisure ride?

Two points in answer:
1. Yes, I'm fit. So was the moped.
2. Yes, a leisure ride - but I said "with hills". Hills make it hard work - towing a heavy load on the flat is easy as once you're up to speed the weight makes no difference.

Mick F wrote:towing a heavy load on the flat is easy as once you're up to speed the weight makes no difference.

Except for the increased rolling resistance

finally, his cycle's on schwalbe tyres

I have to admit the bike has more than one advantage over the Moped

squeaker wrote:

Mick F wrote:towing a heavy load on the flat is easy as once you're up to speed the weight makes no difference.

Except for the increased rolling resistance

Hardly worth the consideration -providing you have good tyres at the optimum pressure.