Play in jockey wheels, replace?

madcarew wrote:

 A little lateral play (side to side of) less than 1 mm is ok (on shimano, don’t know about other brands. On the bottom jockey wheel it is about 3mm built in. If your top one is more than 1mm then replace it.

Don’t you mean the top jockey wheel? Shimano upper jockey wheels are built with a soft lateral movement to make shifts smoother and less noticeable. If you want your Shimano setup to feel more positive, replacing the upper jockey wheel with one of those alloy aftermarket ones without lateral play makes a really noticeable difference, almost Campag-like.

The bottom jockey wheel doesn’t need lateral play, because it’s not forcing the chain across the sprockets in the cassette.

Lateral play in the top

Lateral play in the top jockey wheel is a Shimano patented feature.  Does it make a difference?  Not that I’ve ever felt.

I don’t remember Tacx Shimano replacements having this “feature” and I’ve never felt they gave inferior shifting.

There should be some play,

There should be some play, especially the top one, as it helps the chain when moving across the cassette. Unless they are worn and the teeth are pointy just clean and regrease them and carry on.

After the first ride check you’ve tightened the bolt adequately. The one time I didn’t the bolt on the lower one worked loose and the jockey wheel fell out. Idiot.

I’ve got a 10 speed 105 rear

I’ve got a 10 speed 105 rear mech with about 2,600 miles on it on my desk in front of me (I upgraded to 11 speed). The top jockey wheels moves side to side a good 1mm and the lower one about half a millimetre so I guess some play is necessary.