Jockey Wheels - Ceramic Bearings - Cheap?

Joe Totale wrote:

Aren't AGR2 Mondialle the only pro team using oversized jockey wheels?

I'm sure that if the performance benefits were substantial then all the pro teams would be using them.

DD are as well, don't think many other people are using mixed drivetrain either apart from these two

BehindTheBikesheds wrote:

Spinning them in your hand is a false way to prove they offer less resistance under a load, suggest you forget your plan unless you just want some nice coloured bits to 'bling' up your RD.

You'd actually be better served in actual absolute performance improvement terms by buying a larger toothed (lower position) jockey wheel or tension pulley as some refer to to it, the upper is usually called the pulley or g-pulley and the bits surrounding them is the cage. 

A larger lower wheel eases the amount of angle the chain goes around, so less friction/lower amount of rotations of the bearing, this will have greater effect in effort (which is still maybe 2 watts with a top end system) than a like for like size ceramic replacement over your dura ace. You may have to replace the cage as well however for a larger tooth jockey wheel. 

Would you need to make changes to your chain lengh if you add a larger toothed jockey wheel?

theRomfordRider wrote:

BehindTheBikesheds wrote:

Spinning them in your hand is a false way to prove they offer less resistance under a load, suggest you forget your plan unless you just want some nice coloured bits to 'bling' up your RD.

You'd actually be better served in actual absolute performance improvement terms by buying a larger toothed (lower position) jockey wheel or tension pulley as some refer to to it, the upper is usually called the pulley or g-pulley and the bits surrounding them is the cage. 

A larger lower wheel eases the amount of angle the chain goes around, so less friction/lower amount of rotations of the bearing, this will have greater effect in effort (which is still maybe 2 watts with a top end system) than a like for like size ceramic replacement over your dura ace. You may have to replace the cage as well however for a larger tooth jockey wheel. 

Would you need to make changes to your chain lengh if you add a larger toothed jockey wheel?

potentially, it depends on how tight you were with your chain trimming and your set up with respect to largest sprocket/largest chainring, with the propensity to using big/big you could find that if you have it trimmed to 54 links you might need to go to 55, or 108-110 depending on how you count your links.

personally I rarely ever do big/big, it could probably lose you as many watts as a ceramic and/or larger pulley could save you.  If you buy a new chain that'll lose you 0.5watt to start with until you break it in and if you're going to get a new chain then you might as well spend £40-60 on a decent one to save you another 1-2watts.

Additionally before you trim your new watt saving chain get shot of your 11t sprocket as that is sucking the life out of you. You want a 12T, ideally a 13T starting sprocket and just go with a bigger chainring, again, wider angles equals greater efficiency and applies to the rings/sprockets at higher outputs.

OR, you could just leave the bike as it is

BehindTheBikesheds wrote:

Spinning them in your hand is a false way to prove they offer less resistance under a load, suggest you forget your plan unless you just want some nice coloured bits to 'bling' up your RD.

You'd actually be better served in actual absolute performance improvement terms by buying a larger toothed (lower position) jockey wheel or tension pulley as some refer to to it, the upper is usually called the pulley or g-pulley and the bits surrounding them is the cage. 

A larger lower wheel eases the amount of angle the chain goes around, so less friction/lower amount of rotations of the bearing, this will have greater effect in effort (which is still maybe 2 watts with a top end system) than a like for like size ceramic replacement over your dura ace. You may have to replace the cage as well however for a larger tooth jockey wheel. 

A man with your penchant for numbers will have looked at the data and seen there is no measureable difference on the bike of large vs small, and ceramic vs non-ceramic bearings in jockey wheels.

OP, buy some bling, or don't. There is no operational difference in resistance between your suggested alternatives.

madcarew wrote:

BehindTheBikesheds wrote:

Spinning them in your hand is a false way to prove they offer less resistance under a load, suggest you forget your plan unless you just want some nice coloured bits to 'bling' up your RD.

You'd actually be better served in actual absolute performance improvement terms by buying a larger toothed (lower position) jockey wheel or tension pulley as some refer to to it, the upper is usually called the pulley or g-pulley and the bits surrounding them is the cage. 

A larger lower wheel eases the amount of angle the chain goes around, so less friction/lower amount of rotations of the bearing, this will have greater effect in effort (which is still maybe 2 watts with a top end system) than a like for like size ceramic replacement over your dura ace. You may have to replace the cage as well however for a larger tooth jockey wheel. 

A man with your penchant for numbers will have looked at the data and seen there is no measureable difference on the bike of large vs small, and ceramic vs non-ceramic bearings in jockey wheels.

OP, buy some bling, or don't. There is no operational difference in resistance between your suggested alternatives.

Did you even bother to read my posts at all? The fact i was quoting 0.5 watt increments and saying to leave the bike as is, is a big clue, you really need to upgrade your comprehension skills.

BehindTheBikesheds wrote:

madcarew wrote:

BehindTheBikesheds wrote:

Spinning them in your hand is a false way to prove they offer less resistance under a load, suggest you forget your plan unless you just want some nice coloured bits to 'bling' up your RD.

You'd actually be better served in actual absolute performance improvement terms by buying a larger toothed (lower position) jockey wheel or tension pulley as some refer to to it, the upper is usually called the pulley or g-pulley and the bits surrounding them is the cage. 

A larger lower wheel eases the amount of angle the chain goes around, so less friction/lower amount of rotations of the bearing, this will have greater effect in effort (which is still maybe 2 watts with a top end system) than a like for like size ceramic replacement over your dura ace. You may have to replace the cage as well however for a larger tooth jockey wheel. 

A man with your penchant for numbers will have looked at the data and seen there is no measureable difference on the bike of large vs small, and ceramic vs non-ceramic bearings in jockey wheels.

OP, buy some bling, or don't. There is no operational difference in resistance between your suggested alternatives.

Did you even bother to read my posts at all? The fact i was quoting 0.5 watt increments and saying to leave the bike as is, is a big clue, you really need to upgrade your comprehension skills.

In the post quoted there was no 0.5w increments (you'll have to improve your posting skills, proof reading skills, or typing skills)

If you read my response you will see that I define clearly "Large vs small", Ceramic vs non-ceramic" and state that you'll of course know that there is no evidence of saving on the bike, but you clearly state there is "maybe 2W". So. Improve your typing, reading and comprehension skills. You make numbers up, pull them out of your arse, and chuck them on the page. 

As the chain is under negligible tension going around the jockey wheels there are no effective losses to be gained by decreasing the angle.  And though there are theoretical minor losses to be saved by going to a 12 instead of the 11 there is so far as I know no studies or experiments that have shown this to be measureable or even a real effect. 

The point is moot really. You are so adamant about the veracity of other people's data, or tear it apart according to your own wants, but chuck up any old crap you like, and as pointed out elsewhere, effectively just make it up as you go.