Hi,

Here’s the set up…my 1×10 xt shifter and zee mech have worked perfectly for around 3000 miles.

I have just bought a new bike and got the bike shop to remove the gearing from the new bike and replace it with my xt shifter and zee mech from my old bike. The new bike has a brand new chain, cassette and 34t race face narrow wide chainring.

The chain on the new bike has been left at its original length which was correct for a 36t double, so its a bit long, but not overly so.

Anyway my problem is that on my new bike the chain shifts perfectly up and down the block for all of the gears apart from the smallest cog. It will not drop into the smallest cog properly. There’s normally a few seconds hesitation before it drops, or it won’t drop into the smallest cog at all. It shifts back up from the smallest cog flawlessly however (and across all other cogs).

The bike shop mechanic examined the mech and said it doesn’t shift to the smallest cog because the mech is worn and has play in it. He said I basically need a new mech. Could this be the case? If the mech is worn out, how come it worked fine on my old bike and works fine on all gears (apart from one) on my new bike?

I thought I might just need to adjust the high/low limit screw or ‘fiddle with’ the shifter’s barrel adjuster a bit?

Sorry this has been a long one but I wanted to try and explain exactly what the issue is.

Cheers!

Limit stop, wind the screw out and you’ll be fine

Cheers, I’ll give it a go.

Limit stop +2.

Yes, probably (80% likelihood of being the limit stop ). If these are set correctly and cable tension is good then have a look at b tension (although only playing up in one gear is an unlikely symptom of that).

The other explanation for not getting good shifting across the whole block is a bent hanger. This typically manifests itself as increasingly dodgy shifting towards one end or the other. Just not getting one gear is unlikely with a bent hanger, there should be a series of increasingly imprecise gears in the build up to not being able to get the last one.

Zee mech has a very short cage, so a long chain will have loads of slack in the small ring. I’d chop the chain to the right length and see how that goes.

Check for jockey wheel wear as well as adjusting the lower screw. Also look at the b tension screw as my Zee mech, when too much tension on the screw, would make the jockey wheel run so far away from the sprocket, it wouldn’t jump down , when shifted.

chain length for absolute certain. a slack chain will not allow the mech to work properly in the higher gears (smallest sprocket) get your cable stops and chain length sorted before you look anywhere else

Check the chain length first, I was having the exact same problem and was frustrated for hours before realizing what was going on.

Thanks for all the input. I might need to chop the chain as it was the correct length for a 36t chainring (I have a 34t now) and an SLX mech which is a lot longer than the Zee – never thought about that!

Anyway, I adjusted the limit screw and within a minute the shifting problem was cured!

Cheers again!

I adjusted the limit screw and within a minute the shifting problem was cured

Soddy LBS mechanic not spotting that, you’d expect if that was the problem he would have tried that off the bat – way before recommending a new mech. Jesus.

Yeah. After a visual check, the first tool I would have picked up would have been a cross head screwdriver for the limit stop. Poor show.

I’d even asked the mechanic if the problem was due to the limit screws and after inspection said the mech was worn!