Jockey Wheels. Does it Matter...

[Hugh Manatee]

...If my old and worn wheels have 10 teeth and the replacements have 11? They are obviously slightly larger as a result.

Also, I am used to the top and lower jockey wheels looking a bit different. The upper worn one is chunkier with a more pronounced angular 'shoulder' than the lower one. It also has "Ceramic Bush" printed on it.

The new ones look the same and frankly cheap although the weren't!

Before I soil them by fitting, I thought I would check with those used to more modern stuff.

The mech by the way is an RD6208 600 short cage.

Thanks.

 

[Yellow Saddle]

No it won't matter if they have one more tooth (technically a cog). However, they are supposed to be different. The top one must float laterally on its axle and the bottom one must be rigid. Also, the bottom one is offset to the left to run quieter when cross-chaining. Most/many after market jockey wheels cost the earth, look like jewelry but are technically flawed. The ceramic bearing stamp is a little marketing trick. It is actually a hybrid bush made of bronze and ceramic. However, ceramic is such a high-value marketing attribute that they can't resist putting it on there. The bush could be nylon for that matter, it would still work. The best jockey wheels for your Shimano system are Shimano wheels and it just so happens that they are cheaper too.

 

[Hugh Manatee]

Well, in a reversal of design, the top wheel is now the dull, boring looking thing whilst the lower on has a directional arrow. I'm assuming this as there is a little more lateral float in one over the other.

They are Shimano but won't actually fit. I decided once I read the above to try it as even if it didn't work I have an XT mech in need of them. There isn't enough room for the chain. Every day is a school day. I didn't even know that the humble jockey wheel design had been changed. That's the trouble with being stuck in the past, you have no idea of what's changing!

 

[Yellow Saddle]

Well, in a reversal of design, the top wheel is now the dull, boring looking thing whilst the lower on has a directional arrow. I'm assuming this as there is a little more lateral float in one over the other.

They are Shimano but won't actually fit. I decided once I read the above to try it as even if it didn't work I have an XT mech in need of them. There isn't enough room for the chain. Every day is a school day. I didn't even know that the humble jockey wheel design had been changed. That's the trouble with being stuck in the past, you have no idea of what's changing!

The directional arrow is there not because that one's bearing doesn't like going in reverse, but because that is the offset wheel. Eye-ball it head-on and you'll see that the row of cogs are not in the middle, but slightly offset to the right.

 

[migrantwing]

Tacx make very good replacement jockey wheels but, on your appraisal of Shimano, I will try them next time, @Yellow Saddle.