Rear mech trouble.

freehub

Can't remember if I've posted about this.

But anyway.

I'm struggling to get the rear mech shifting properly, I've tinkered with the cable tension and the screws and it's still not avin it.

I find that shifting up, from the smallest cog on the cassette, and then on for most of the cogs, I need to double click, then click down one to get it right, sometimes, if I carefully and slowly push the shifter, it may shift correctly. But it's a right mess about at the moment.

Any idea what to do?

iain_j

freehub wrote:

I've tinkered with the cable tension and the screws and it's still not avin it.

If mine goes that way I scrap it off and start again - undo the cable bolt on the mech and set it up again from scratch (chain on smallest sprocket, shifter likewise, barrell adjuster fully tightened then backed off one of two turns, set cable taut, adjust).

freehub

I've done that, still not avin it

redddraggon

About time you Upgraded from Shimano to Campag or SRAM

CarlosDSanchez

Are the cables and cable outers in good condition? When did you last clean and lube them? If they're looking a bit sad it might be time to replace them. Also how is the guide pulley on the rear mech? If the teeth are worn or there's excessive bearing wear it will make shifting less acurate.

nmcgann

That could be a symptom of wear in the main pivot. Look here: http://www.parktool.com/repair/readhowto.asp?id=76 at the diagram with the blue arrows.

Wear in the top jockey wheel bearing can have a similar effect.

I just replaced a mech with wear like this as it wouldn't shift properly, especially around the middle of the cassette. It was also just catching the spokes when on the inner cassette cog.

jgsi

nmcgann wrote:

That could be a symptom of wear in the main pivot. Look here: http://www.parktool.com/repair/readhowto.asp?id=76 at the diagram with the blue arrows.

Wear in the top jockey wheel bearing can have a similar effect.

I just replaced a mech with wear like this as it wouldn't shift properly, especially around the middle of the cassette. It was also just catching the spokes when on the inner cassette cog.

I was also going to recommend taking the rear mech off completely and checking it for smoothness etc... giving it a thorough diesel wash and clean...but it could be just wear and tear and replacement time however

Ben6899

JGSI wrote:

I was also going to recommend taking the rear mech off completely and checking it for smoothness etc... giving it a thorough diesel wash and clean...but it could be just wear and tear and replacement time however

+1

I just had to replace a Campag Veloce one I was having problems with. When I took it off the bike to inspect, it was very clear it wasn't moving as freely as it should. Unfortunately, all matter of cleaning didn't fix it so I had to give Parker a call.

Good luck.

SCR Pedro

It sounds similar to a problem I had.

It turns out that I had put the cable fixing bolt on incorrectly. No.5 here.

I had the raised side of it clamped against the cable. It should go on as you see it in the diagram.

Pedro

shockedsoshocked

Have you adjusted it using the barrel adjuster? shift it to the middle of the sprocket (5/6th) and align the jockey wheels. Might take a little fine tuning.