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Date: 12 May 2007 04:56:56
From: me
Subject: 20 vs 26 in wheels
Does anyone have direct experience of using at bike with 20 in wheels and
one with 26 in wheels but with the same brand and model of tire?

Which would feel easier to pedal?




 
Date: 12 May 2007 18:11:45
From: Jay - BFri Commuter
Subject: Re: 20 vs 26 in wheels

"me" <me@nowhere.com > wrote in message
news:sOb1i.174541$DE1.5023@pd7urf2no...
> Does anyone have direct experience of using at bike with 20 in wheels and
> one with 26 in wheels but with the same brand and model of tire?
>
> Which would feel easier to pedal?

In other words, which wheel size would be faster? Because if, for instance,
the 26" wheel felt easier to pedal, one would be inclined to pedal faster,
to reach the same level of exhaustion as the mope on the 20" wheels.

I agree with the earlier replies, that wheel size does not matter much,
compared with the other factors which prevent one's bike from being a
perpetual motion machine.

It would definitely not be difficult to prove mathematically that bike wheel
size per se, does not matter. I am embarrassed to admit that I cannot
supply such a proof. It has been too many years since I have had the daily
academic challenge of 'word problems'. But coming up with your 'wheel size
differential proof' would have been a perfectly appropriate assignment in
several of my undergrad math or physics classes.

Of course, the 20" wheel will rotate at greater RPM than the 26" wheel, at a
constant bike speed. But at the relatively low RPM a bike can generate, I
don't think the wheel size difference would be significant.

I have had complete strangers try to convince me (while paused on my daily
commute), that my 20" wheels must certainly be slower than larger wheels.

Another fellow was sure that my bike has significantly less aerodynamic
drag, because I am several inches closer to the ground than larger bikes.

Best thing one can do when faced with such conversations, is to smile and
say 'I'm sure you are right', and continue on to your destination - J.




 
Date: 12 May 2007 08:25:26
From: peter
Subject: Re: 20 vs 26 in wheels
me wrote:
> Does anyone have direct experience of using at bike with 20 in wheels and
> one with 26 in wheels but with the same brand and model of tire?
>
> Which would feel easier to pedal?

I don't stick with one particular tire brand, but I ride both a Bike
Friday, with 20" (451mm rim size) wheels, and a few bikes with
27" (700C or 622mm rim size) wheels, most frequently a Cannondale road
bike. Both use lightweight tires/tubes with minimal tread pattern.
The gearing must be modified to get equivalent speeds vs. cadence on
both bikes. In my case, the Friday uses 42 and 60 teeth chainrings
and an 11-28 cluster whereas the Cannondale has 39 and 52 teeth
chainrings and a 13-32 cluster. That makes for pretty close to the
same effective range of gears for both bikes.

Larger diameter wheels are inherently smoother going over potholes and
bumps, so to compensate I use slightly wider tires on my 20" wheel
Friday. Usually I have 28 to 32 mm wide tires on it while I have 23
to 25 mm tires on the Cannondale. Tire pressure in both is about the
same at 110 psi, but I find that decreases in the tire pressure are
much more noticeable on the Friday. It becomes sluggish if the
pressure drops below about 80 psi while the Cannondale still rides
easily at that pressure (but becomes subject to pinch flats when
hitting bumps).

I'm sure the rolling resistance of the 20" wheels is still a little
higher than the 27" (700C) wheels even when both are at the 110 psi
pressure, but the difference is pretty small and usually other forms
of drag dominate over rolling resistance. On flat rides wind
resistance is much more important and on very hilly rides the effect
of gravity dominates.



 
Date: 12 May 2007 15:18:41
From: me
Subject: Re: 20 vs 26 in wheels
On Sat, 12 May 2007 00:05:38 -0700, Tom Keats wrote:

> In article <sOb1i.174541$DE1.5023@pd7urf2no>,
> me <me@nowhere.com> writes:
>> Does anyone have direct experience of using at bike with 20 in wheels and
>> one with 26 in wheels but with the same brand and model of tire?
>
> That's an interesting question, and one to which
> I'd have to answer: no.
>
>> Which would feel easier to pedal?
>
> It's not entirely how big your wheels are ... it's how
> you use them. Air resistance and available gearing
> has something to do with it, too.
>
> But I'll tell yuh what -- I've got this old, folding
> Raleigh Twenty, and it's a beauty. Orig chrome fenders,
> chain guard, 'n all. And the original Raleigh tires
> in good condition. When I wind 'er up the thing goes
> like stink. And that's with the ol' S-A 3-speed, and
> my ability to kick-in a high cadence when I can.
>
> I also have an old MTB that I've converted to a
> City Bike, and it's a beauty too. In fact, it's the
> best City Bike in the world.
>
> So ... what do you mean by "easier to pedal"?
> Any bike can be rendered "easy to pedal".
>
> I think maybe you're asking: "which bike is faster?"
>
> As if that matters.
>
>
> cheers,
> Tom
>

LOL

I have the opportunity to test a 20 in bike with some tires I am
interested in. ( Schwalbe Big Apple ) I have read, and been told,
that they are a lot easier to pedal than their balloon like
appearance would suggest.Cant find anyone local that has a 26 in
with them on.


 
Date: 12 May 2007 00:05:38
From: Tom Keats
Subject: Re: 20 vs 26 in wheels
In article <sOb1i.174541$DE1.5023@pd7urf2no >,
me <me@nowhere.com > writes:
> Does anyone have direct experience of using at bike with 20 in wheels and
> one with 26 in wheels but with the same brand and model of tire?

That's an interesting question, and one to which
I'd have to answer: no.

> Which would feel easier to pedal?

It's not entirely how big your wheels are ... it's how
you use them. Air resistance and available gearing
has something to do with it, too.

But I'll tell yuh what -- I've got this old, folding
Raleigh Twenty, and it's a beauty. Orig chrome fenders,
chain guard, 'n all. And the original Raleigh tires
in good condition. When I wind 'er up the thing goes
like stink. And that's with the ol' S-A 3-speed, and
my ability to kick-in a high cadence when I can.

I also have an old MTB that I've converted to a
City Bike, and it's a beauty too. In fact, it's the
best City Bike in the world.

So ... what do you mean by "easier to pedal"?
Any bike can be rendered "easy to pedal".

I think maybe you're asking: "which bike is faster?"

As if that matters.


cheers,
Tom

--
Nothing is safe from me.
Above address is just a spam midden.
I'm really at: tkeats curlicue vcn dot bc dot ca