Bicycle Mechanics - Friction Weenies

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View Full Version : Friction Weenies


danarnold
11-01-09, 05:47 PM
OK... admit it. You're a closet friction weenie. You don't want to push one unnecessary microgram extra effort.

So... Fellow FW's where do you reduce friction?

I may as well confess I was polishing the Bishop (that's what I call my bike) and I noticed the Speedplay pedals, newly greased, seemed sluggish. This seemed WRONG. They should spin like wheels. Why should I spend the least extra effort to make the Bishop come... or go?

So... please respond with your friction reducing tips.


HillRider
11-01-09, 06:32 PM
OK... admit it. You're a closet friction weenie. You don't want to push one unnecessary microgram extra effort.

So... Fellow FW's where do you reduce friction?

I may as well confess I was polishing the Bishop (that's what I call my bike) and I noticed the Speedplay pedals, newly greased, seemed sluggish. This seemed WRONG. They should spin like wheels. Why should I spend the least extra effort to make the Bishop come... or go?

So... please respond with your friction reducing tips.
Most pedals don't spin like a top when you flip them so there is nothing wrong with yours. My Frogs do the same thing, particularly right after they have been grease injected.

If you want the bearings to spin more freely, clean out all of the grease and use light oil. The pedal bearings might not last very long but they will be low friction. :rolleyes:

If you want minimum friction, and hang the cost, then get ceramic bearings everywhere. The benefits are very small and the cost outrageous but they will reduce friction.

oldbobcat
11-01-09, 08:00 PM
Pedals will never spin like a wheel until they're made to weigh around 700 grams each with about a 60 cm long platform. It's the mass and diameter of the wheel that keeps spinning.

On a more practical note, your newly greased pedals will feel sluggish until the balls push a wide enough track through the grease.


nateintokyo
11-01-09, 09:30 PM
Moral: stop polishing your bishop and push your balls through the greasy track!

tadawdy
11-01-09, 09:57 PM
well, lower friction tires feel nice. a nice, smooth bottom bracket feels good, too. Drivetrains are, I think (from Bicycling Science) around 90% efficient, given proper setup. With wear, insufficient lube, etc, this will fall. So that's one place to look.

On normally functioning bikes, though, aerodynamic drag is WAY more important than internal losses and rolling resistance, unless you only ride very slowly. So, just getting a little lower and wearing tighter-fitting clothing is a better bet, and more cost-efficient, for most of us.

ottothecow
11-01-09, 10:14 PM
My new (first) external bearing BB sure feels like its got more friction

I still like it better

markieta
11-01-09, 10:31 PM
My new (first) external bearing BB sure feels like its got more friction

I still like it better

That will work in fairly quickly.

tadawdy
11-01-09, 11:59 PM
That will work in fairly quickly.

It seems that the new cartridges take a little while to "wear in." I almost took mine in because it was annoying me a little. After a couple hundred miles, it settled in and is perfectly fine.

HillRider
11-02-09, 06:23 AM
It seems that the new cartridges take a little while to "wear in." I almost took mine in because it was annoying me a little. After a couple hundred miles, it settled in and is perfectly fine.
The initial drag is usually due to the tight new seals. As they wear slightly, the bearing feel smoother and have less apparent drag.

nitropowered
11-02-09, 09:00 AM
You can get ceramic bearings for speedplay pedals. Clean out the grease, take off the o-ring on the spindle and use light oil

danarnold
11-02-09, 09:26 AM
Moral: stop polishing your bishop and push your balls through the greasy track!

BTDT Thanks for reminding me =o)

BikeWise1
11-02-09, 10:52 AM
A bike is about the most efficient device on earth even when it's a *** Huffy. YOU are the part that needs the most attention. Your position on the bike, and your aero-cleanliness make more of a difference than anything you can do to bike. Get rid of the fluttering jersey!

That said, when I was a Pursuit specialist, I ran oil in the hubs and very light grease in the BB.

People will argue this until the end of time, but I think unless you are running a newer DA, Red, or high-end Campy derailleur, adding some ceramic pulleys to your rear derailleur(particularly if you aren't the type to disassemble and re-lube them often) makes a big difference.

mrrabbit
11-02-09, 11:28 AM
Yeah...I agree...we need to focus on the rider for friction reduction:

1. Wear slightly looser and very smooth silk women's underwear.
2. See the local barber to go eagle.
3. Get a Brazillian girlfriend/boyfriend for a Brazillian body hair removal experience.
4. Speedos for bike shorts, sports bra for jersey.
5. Kung-Fu shoes - drill your own holes.
6. Buy life insurance...cause you ain't wearing a brain bucket.

=8-)

mconlonx
11-02-09, 01:11 PM
Get a bike with adjustable bearings everywhere there are bearings. Tear it down, flush all the grease out, apply light oil, remove one bearing from each set.

Learn how to adjust bearing tension properly. Adjust bearings as necessary. Probably every other day or so...

Lowest friction comes at a price: $$$ for ceramic; your time and skill learning to play with adjustable bearings.

DMF
11-02-09, 02:04 PM
on normally functioning bikes, though, aerodynamic drag is way more important than internal losses and rolling resistance, unless you only ride very slowly. So, just getting a little lower and wearing tighter-fitting clothing is a better bet, and more cost-efficient, for most of us.

+1

davidad
11-02-09, 03:05 PM
well, lower friction tires feel nice. a nice, smooth bottom bracket feels good, too. Drivetrains are, I think (from Bicycling Science) around 90% efficient, given proper setup. With wear, insufficient lube, etc, this will fall. So that's one place to look.

On normally functioning bikes, though, aerodynamic drag is WAY more important than internal losses and rolling resistance, unless you only ride very slowly. So, just getting a little lower and wearing tighter-fitting clothing is a better bet, and more cost-efficient, for most of us.
"Bicycle Science" doesn't even devote two full pages to bearings. They are not an important factor in power loss.