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cnighbor1
05-29-2011, 08:00 PM
Were does get the biggest advatage on weigth saving on a bike.
1. Wheels
2. Frame
3. Fork
4. Components
5. Losing some body weigth
6. Clothes
7 Accessiories (pump, tools, ligths,etc)
I say wheels due to having to accerate and reaccerate them over many miles
Charles

weiwentg
05-29-2011, 08:03 PM
Your own fat a##

Wheels

Components

Frame/fork within reason

bart998
05-29-2011, 08:07 PM
Your own fat a##

Wheels

Components

Frame/fork within reason


Agreed!

biker72
05-29-2011, 08:07 PM
Body weight.....and width... :D

billythekid
05-29-2011, 08:21 PM
Rotational weight. Tires, tubes, rims, crank. Anything you're spinning matters. The rest . . . not so much. Although none of it is going to help you much if you're out of shape!

mcewen
05-29-2011, 09:31 PM
Rephrase the question:

Q: Where would a 1lb weight loss do the most good?

A: On the wheels. Wheels have static inertia AND rotational inertia. So do the cranks and pedals, but their moment of inertia is much smaller than the wheels. The chain that is contacting the chainrings and cogs do too, but you cannot lose weight off your chain.

So, a POUND lost off your wheels will have a bigger effect on performance than a POUND lost off your body, frame, fork, gruppo or elsewhere. The effect will be greater the more the lost mass is concentrated towards the rims, tubes and tires as the farther the lost mass is located from the center of rotation, the lower the moment of inertia will be.

Mark McM
05-29-2011, 09:52 PM
So, a POUND lost off your wheels will have a bigger effect on performance than a POUND lost off your body, frame, fork, gruppo or elsewhere. The effect will be greater the more the lost mass is concentrated towards the rims, tubes and tires as the farther the lost mass is located from the center of rotation, the lower the moment of inertia will be.

This above is true of course, but be careful not to over emphasize the importance. During accelerations, the mass at the periphery of the wheel (rims, tires, tubes) has twice the inertia as compared to non-rotating mass. But that only matters during accelerations - for climbing, a pound is a pound regardless of where it is on the bike. And for riding at a steady speed on a flat road, mass of any kind matters only a small amount.

Also keep in mind that a bike only has 3 - 4 pounds total of rotating inertia, so there's only an opportunity to at most a pound or so of rotating mass. As others have pointed out, there's usually far more mass that can be lost on the rider - and this is a typically a much more cost effective mass saving effort, since instead of having to spending more money (on new equipment), you can usually do by spending less money (on food).

David Kirk
05-30-2011, 12:34 AM
Wheels.
Shoes.
Pedals.
All else.
In that order.


dave

godfrey1112000
05-30-2011, 05:55 AM
Agreed!


yes, less in the pie hole

jpw
05-30-2011, 06:14 AM
Wheels.
Shoes.
Pedals.
All else.
In that order.


dave

Shoes - I ride with light road and heavy mtb shoes (thick heavy soles and treads) and there is quite a big difference. The mtb shoes are sluggish, but sometimes being able to walk is helpful.

oldpotatoe
05-30-2011, 08:36 AM
This above is true of course, but be careful not to over emphasize the importance. During accelerations, the mass at the periphery of the wheel (rims, tires, tubes) has twice the inertia as compared to non-rotating mass. But that only matters during accelerations - for climbing, a pound is a pound regardless of where it is on the bike. And for riding at a steady speed on a flat road, mass of any kind matters only a small amount.

Also keep in mind that a bike only has 3 - 4 pounds total of rotating inertia, so there's only an opportunity to at most a pound or so of rotating mass. As others have pointed out, there's usually far more mass that can be lost on the rider - and this is a typically a much more cost effective mass saving effort, since instead of having to spending more money (on new equipment), you can usually do by spending less money (on food).

What he said......

But spending $ on equipment is easier than becoming fit and thin(artifically thin, according to Lemond).

Too much of 'buy speed', not enough riding...

MadRocketSci
05-30-2011, 03:55 PM
weight is more an issue of "feel" rather than performance, unless you measure performance by bike lengths and seconds....

2ndproyer
05-31-2011, 03:54 PM
1)my aging body
2) my lack of flexibility, ie being more non-aero
3) wheels, I know I have noticed the difference!

sbparker31
05-31-2011, 04:05 PM
I like pie.

RPS
05-31-2011, 04:39 PM
Rephrase the question:

Q: Where would a 1lb weight loss do the most good?

Most good under what conditions?

Riding downhill I'd expect you'd want to add weight. :)


For what it's worth, I've always thought that for a given amount of total mass, greater inertia can be a good thing when doing long climbs.

Mark McM
05-31-2011, 05:50 PM
For what it's worth, I've always thought that for a given amount of total mass, greater inertia can be a good thing when doing long climbs.

That's similar to what Ondrej Sosenka thought when he set the Hour Record. He used heavy wheels, supposedly because the 'flywheel affect' would make it easier to maintain a high speed.