Movement in derailleur mounting screw. Normal ?

[maltloaf]

During some general cleaning and adjusting yesterday, I noticed that there seems to be a fair bit of play in the mounting between my (Tiagra 10 speed) rear derailleur and the gear hanger.

The bolt is done up completely and tight, the movement is actually in the bushing and whilst not that much there, translates to quite a lot by the time you get to the jockey wheels.

I have no idea, however if this is normal.

Shifting is mostly spot on but I have been getting the odd mysterious clonk clonk clonk now and then which will come randomly for a few minutes and then often disappear for the rest of the ride.

Also, I have had trouble staying in bottom gear (34/30) when under load which can be a right pain (literally) as when I need that gear, I REALLY need that gear ! The limit and indexing seem to be correctly adjusted, it only happens under load.

Are the two connected ? Is a bit of movement in that bushing normal ? How much is normal ?

The derailleur has done about 3000 miles since last October, which doesn't seem much to me but any advice gratefully received.

Thanks,

Malty

 

[RebornBumbler]

I don't think there should be any significant play at all - though obviously it shouldn't be stiff.
Sounds like a new derailleur unless it's something like a missing/broken washer - you might be able to get parts, but I suspect a new unit is only twenty quid.

 

[maltloaf]

Thanks. I didn't think there should be any play at all but didn't want to buy a new one just to find it was the same. I see 105 derailleurs are £27 new so may well order one of those today.

Thanks again.

 

[Deleted member 35268]

Worth removing it and inspecting the inner tightening bolt, see if it goes back on again tighter. However, my Tiagra rear mech was loose like yours after about 5K (probably sooner). Not sure if it can be repaired.

Oh, and another thing - my (new) chain is jumping around like crazy on the smaller cogs, even though my mech is new, so looks like I need a new cassette. Money money money.

 

[maltloaf]

I took it off and it all looked clean and tidy enough and certainly did up fine. It looks like there is a plastic sleeve/bush between the bolt and the rest of the derailleur which I think must be worn down a bit.

I have a new chain, new chainset and soon to be new mech it seems. I don't get many shifting problems but the chain did manage to chuck itself off today, something I haven't had in years !

 

[uclown2002]

I have shimano 105 RDs on 2 different bikes and there is a little bit of play on both, so perhaps it is normal. Possibly 5-6K miles on them both.

 

[Andy_R]

I took it off and it all looked clean and tidy enough and certainly did up fine. It looks like there is a plastic sleeve/bush between the bolt and the rest of the derailleur which I think must be worn down a bit.

I have a new chain, new chainset and soon to be new mech it seems. I don't get many shifting problems but the chain did manage to chuck itself off today, something I haven't had in years !

Paging Dr @Fnaar .....I'm sure you can come up with a suitable innuendo........

 

[fossyant]

You can get a little play, but if it becomes excessive, it's time to change.

 

[maltloaf]

I've ordered the 105 one, I'll report back how much different it is.

Thanks everyone for the input

 

[fossyant]

The easy tell tale is how much can you wiggle the cage on the rear mech. If you've got significant side to side movement, its worn.

 

[maltloaf]

Fitted my new 105 derailleur this morning, almost zero play in the pivot screw bushing. Much much less than the old one.

I was also staggered how much play there was in my old jockey wheels. The new ones have some left to right movement (as I believe they should) but no pivoting. The old ones would pivot maybe 10 degrees !

Everything feels nice and smooth. Quick test ride seemed nice and crisp, shifting wise. Longer ride this afternoon hopefully.

Thanks everyone

malty.