Stupid question but...

[Q]

How come no bicycles are FWD? I'm being serious, why have they always been RWD? What is the advantage?

 

[pstylesss]

duh, you can't do wheelies on a FWD bike... :roll:

 

[soydios]

FWD would have massive torque steer. Imagine: your try to pedal in a turn, only to have the bottom-front of the bike fly out from under you.

Physics way: the force from the tire would not be directed 100% towards the center of mass.

 

[LordMorpheus]

There have been some all wheel drive bikes. I think some of BMW's large touring bikes had all wheel drive.

There's also some kit to let you drive both wheels of a dirtbike, they found a way to eleminate the torque steer (counterrotating drive shafts or something) so you can get more traction.

 

[LS21]

uh... how would you turn the front wheel

 

[jlee]

Originally posted by: Quintox
How come no bicycles are FWD? I'm being serious, why have they always been RWD? What is the advantage?

Because FWD is a technologically inferior alternative? Care to give any reasons why someone should even consider it?

 

[OdiN]

Originally posted by: soydios
FWD would have massive torque steer. Imagine: your try to pedal in a turn, only to have the bottom-front of the bike fly out from under you.

Physics way: the force from the tire would not be directed 100% towards the center of mass.

Yeah and try pedaling uphill with a FWD bike.

 

[Tiamat]

 

[thirtythree]

Maybe I'm missing something here, but I don't think it would work to have a chain hooked up to the front tire... since the front tire turns, the chain would either restrict turning or loosen up and fall off.

EDIT: Ah, I see LS21 realized this.

 

[George P Burdell]

Originally posted by: LS21
uh... how would you turn the front wheel

This is what I was thinking.

 

[Jeff7]

Originally posted by: soydios
FWD would have massive torque steer. Imagine: your try to pedal in a turn, only to have the bottom-front of the bike fly out from under you.

Physics way: the force from the tire would not be directed 100% towards the center of mass.

Not to mention that putting the bike chain to a wheel that pivots would probably cause lots of problems.
Unless you can solve that pesky problem of matter (generally) being unable to pass through other matter, in which case you'd probably forget about the bike problem, as you're accepting your Nobel Prize.

There's no heavy engine sitting over the front wheels either, so another benefit of FWD is lost.

 

[sash1]

what about those oldschool bikes with the really big front wheel and the small back wheel?

 

[thirtythree]

Originally posted by: sash1
what about those oldschool bikes with the really big front wheel and the small back wheel?

Click Tiamat's smiley.

 

[beat mania]

Originally posted by: thirtythree
Maybe I'm missing something here, but I don't think it would work to have a chain hooked up to the front tire... since the front tire turns, the chain would either restrict turning or loosen up and fall off.

EDIT: Ah, I see LS21 realized this.

The mechanical connection would have to go up to the handle then down the forks of course. Some sort of drive shaft would probably be easier to implement.

 

[Kadarin]

Originally posted by: LS21
uh... how would you turn the front wheel

Even if you had a drive system that would handle it, you'd still have the gyroscope effect.

 

[Auggie]

Originally posted by: Tiamat

hehe, I missed this until thirtythree got me to look at it...

 

[Jeff7181]

How would torque steer be an issue with a single driven wheel? Do you know what torque steer is?

 

[thedarkwolf]

AWD close enough?

 

[Eli]

Originally posted by: thedarkwolf
AWD close enough?

That's badass.

Not only is it AWD, but it's smart AWD - diverting power to the other wheel when one slips.

Neat.

 

[Amused]

AWD drive off road motorcycles:

http://www.christini.com/

http://www.motorcycle-usa.com/...ge.aspx?ArticleID=4079

AWD mountain bikes:

http://christinibicycles.com/

 

[angry hampster]

Imagine hitting the front brake hard on a FWD motorcycle. :laugh: That's potentially 30-40lbs moved from the rear to the front.

 

[grrl]

Originally posted by: Amused
AWD drive off road motorcycles:

http://www.motorcycle-usa.com/...ge.aspx?ArticleID=4079

>>Perhaps the best known option for real off-road motorcycling up till now has been the hydraulic Ohlins system. Developed in conjunction with Yamaha for the WR450F, the Ohlins setup has one major drawback that seems to be universally bitched about - sapping engine power. Christini claims that the total amount of loss with their AWD system is 1/10th of a horsepower. Natural speculation combined with our quick riding impression has left us to doubt it truly drags so little. However, we're certain that whatever it is, it isn't much.

I was wondering about power loss. That doesn't seem like much considering all the gears and sprockets required.

 

[Colt45]

Originally posted by: angry hampster
Imagine hitting the front brake hard on a FWD motorcycle. :laugh: That's potentially 30-40lbs moved from the rear to the front.

Same thing that happens when you slam the front brake on a normal bike?

 

[dennilfloss]

Early bikes (velocipedes) were FWD.

http://en.wikipedia.org/wiki/I...merican_Velocipede.jpg
http://www.indymedia.be/files/velocipede.jpg
http://www.paughsome.com/images/sepia-velocipede.jpg
http://fac-staff.seattleu.edu/dohertyd/web/img/velocipede.jpg

 

[wetcat007]

It'd be overly complex when it comes to turning, also on a typical bike you have more weight over the rear wheel.