dream super bike

[Saundie]

why wouldn,t you want an automatic gear that put you in the right gear for the speed your doing. ?

It'll almost certainly be heavier than the existing gear systems, and extra weight is most unwelcome on a vehicle you have to power yourself.

the intersting point about power required to turn the pedal, - have you ever seen a man push a train, once its moving its own weight and momentum carries it along
all you need is a lesser ratio to get you get going and the bigger ratios can be engaded

Have you ever seen a man push a train at 100mph? He may be able to get it to move a few yards at walking speed, but that's as far as it goes. You seem to be missing the fact that you need a huge amount of torque in order to turn a huge gear - it's not a matter of simply "getting up to speed".

 

[Rob3rt]

why wouldn,t you want an automatic gear that put you in the right gear for the speed your doing. ?

the intersting point about power required to turn the pedal, - have you ever seen a man push a train, once its moving its own weight and momentum carries it along
all you need is a lesser ratio to get you get going and the bigger ratios can be engaded

Why the hell WOULD you want it? It is counter intuitive! If you are so ignorant to the dynamics of cycling, you are the last person who ought to be designing a bike.

You don't have a clue!

 

[fossyant]

Have you ever seen a man push a train at 100mph? He may be able to get it to move a few yards at walking speed, but that's as far as it goes. You seem to be missing the fact that you need a huge amount of torque in order to turn a huge gear - it's not a matter of simply "getting up to speed".

Dead easy, in my awesomeness, I could ride single handed, one arm on the train, one on the bars and pedal that train to 102 mph with my fixed gear bike, whilst on the phone to order my pizza at the end ! OK !

 

[fossyant]

 

[mickle]

Ye of little faith! I think it's a great idea and the OP should be encouraged. It it wasn't for such optimism and innovation we'd all be driving around in cars made out of boulders like off of the Flintstones.

 

[fossyant]

I smell something........

 

[dan_bo]

Ye of little faith! I think it's a great idea and the OP should be encouraged. It it wasn't for such optimism and innovation we'd all be driving around in cars made out of boulders like off of the Flintstones.

Hey Mick- you might be on to something there!

 

[fossyant]

Ye of little faith! I think it's a great idea and the OP should be encouraged. It it wasn't for such optimism and innovation we'd all be driving around in cars made out of boulders like off of the Flintstones.

Stop causing trouble you ! Even you know physics rather well.

 

[ayceejay]

The only way this would work is to build a really heavy aerodynamic bike then find a 40 mile long hill (downward slope)and somehow get you massive bike to the top of this hill. Using the train analogy as a guide you only need to set the bike in motion and gravity will take care of the rest, this way you don't need any gears, maybe some brakes if you lose your bottle. If money is no object you could build your own hill or use the money you saved on gearing.

 

[dan_bo]

 

[fossyant]

This old bugger is quite handy at doing over 30 mph for a long time. Got a fancy bike too with big (ish) gears. Dead easy this riding fast. Just don't mention the battery (it's in his leg he's a Cyberman) !

 

[Licramite]

design daft 1
you do know I,m going to have to build the sodding thing now , just to prove it won,t work don,t you
thanks guys.

well if I didn,t want the piss taken out me , shouldn,t have joined the para.

 

[Rickshaw Phil]

Wind resistance is a big problem, the Lightning (aircraft) solved its rubbish aerodynamics by overpowering (with enough power you can make a brick fly) so with way more power than it needs it doesn,t have to run effeciently, so if 1revolution/second(1Rs)=18mph@100%effeciency , then at say 50% effeciency you still only need 3Rs to do 27mph.

I'm afraid you are still confusing high gearing with power. Making the bike higher geared will not automatically make it fast. The design you have posted is a step in the right direction as you have what appears a more aero posture but I feel it is still not enough.

If making a bike fast was as simple as putting the tallest possible gear on then believe me, we would all be running round with 80 tooth big rings.

You say you are averaging 10-12 mph in one of your posts and you are obviously dissastified with this. How much of your riding is in the big ring? Your biggest gear will be good for cruising at 25 to 35 mph if you are strong enough, depending on whether you have a freewheel (14 tooth top gear) or a cassette (11 tooth top gear). How often are you cruising at these speeds?

 

[Rob3rt]

You say you are averaging 10-12 mph in one of your posts and you are obviously dissastified with this. How much of your riding is in the big ring? Your biggest gear will be good for cruising at 25 to 35 mph if you are strong enough, depending on whether you have a freewheel (14 tooth top gear) or a cassette (11 tooth top gear). How often are you cruising at these speeds?

Never!

 

[Licramite]

oddly I,m quite happy with my cycle speed - on the flat bits I get to 17mph but they are few, the terrain I cycle over , off road/on track/on road , up and down hill & dale the bike would be useless,
I was going to get aerobars but I wouldn,t use them, I don,t do flat straight bits enough.

but as a commute machine it would be ace.

I think its going to need a 2 stage chainset, a smaller set for low speed and hills then a link to the high speed set
Im looking for a motorbike look, solid wheels front and back and a fairing over drive wheel. drop handlebars.
I have no illusions about the drive resistance - and thats the thing I can,t calculate
the drag I probably can calculate , - Ive got a program for aircraft, don,t know if it goes to such pifling speeds.
the only way is to build it and see.

I will invite you all to stand and laugh as I fall off,