Jockey wheel float

For Shimano top jockey wheel, how much float is too much float? I’m having a complete mare trying to index my shifts, sounds fine on the stand but outside after a couple km it’s noisy as about to shift. I’ve indexed things a million times but it’s just not playing ball, I not sure constantly swapping wheels for turbo and outside helps.

If I take the rear wheel out (say swapping between road and turbo wheels) I can hear it rattling as I move the bike.

I’ve got a couple videos but just need to find somewhere to host them which shows the noise/amount of play.

From memory a couple mm each side is normal.

Probably completely unhelpful, but are the cassettes the same size on the trainer and on your road wheels? If not could be b-tension. Or something I often do is ram a skewer closed far too tight for how your indexing is set up - possibly another thing to look out for.

11-30 on the road, and 11-32 on the turbo wheel, I was swapping wheel plenty often it just this last few weeks of head-scratching. Skewer will be something to check, I don’t really care about indexing inside I just want outside to be nice!

Never heard rattling, never really looked out for it either, which is why I’m wondering about float. But it could be the case of now I’ve noticed it I can really hear it. A bit of a self-fulfilling prophecy!

Derailleur hanger alignment would be a good place to start.

Just to follow up… good b-tension adjustment will just help it shift a crisper, but if you swap cassette sizes a lot then you maybe don’t want to faff with the b-tension each time. At the least, I’d make sure that on the larger cassette of the 2 that the b-tension is totally on point. Loosen the b-tension bolt until the top jockey wheel is rubbing the cassette in lowest gear, then tighten the bolt 1/4 turn and re-check. Repeat until it doesn’t rub.

If it persists outdoors, it’s probably worth doing the same on the outdoor setup to see if it helps.

That was the last thing other than jockey I could think of, sadly that is a shop job since I don’t have the tool for it.

Here is the awesome video: https://youtu.be/RuFbGQU2KBE

Someone showed a beautiful hack for that not long ago - using a spare wheel that you mount on the hanger.

My jockey wheels do the exact same thing. One is on RED eTap, the other Ultegra Di2. Both are ceramic/aluminum, not that it matters.

I suspect your shifting issue is not related to the pulleys themselves.

Agreed. The lateral play in the top jockey wheel is there to ensure it will float laterally and reduce the impact of any lateral misalignment of the cage from pushing the chain sideways. The symptom of “too much sideplay” would be during the shifts (requiring more cage movement to get the chain over), not once the shift is over.

Tbh I was thinking the same thing, rattling was a bit of a last ditch idea before she goes into the shop for alignment checking.

Hi @firemunki! I have a spare 105 rear derailleur in my hands right now with stock shimano jockey wheel in it. The tension pulley has a millimeter or less of play in it. The centeron pulley lot more play…more than 2mm but less than 3mm I’d say.

Both pulleys are about 8mm wide at the metal flange.

I don’t know if this helps but there is some info for ya!