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Long story short, new bike has never shifted right and I was too lazy to investigate until today.
The rear mech is behaving like it's too far inboard. It's just very slow and reluctant to shift down the block to the small sprocket and it's always rubbing on the bigger one. I assumed I'd bent something in the Wharncouver crags but everything appears straight.
Anyway, I took the rear mech off and the bolt has a lot of play in it. The plastic spacer on the back is very loose and floppy. It's like it's missing a circlip or washer or something.
So if you have one and you're able to check, does this look normal?
So, I stuck a big washer behind it, like this and it fixed the problem instantly.
So is something missing from the back of the derailleur?
It looks like the circlip is missing.
Best bet is to get on the shimano EU website and plug the full model number in and get the exploded diagram up in front of you.
Exploded view:
As above, looks like the circlip is missing. However, it shouldn't make any difference once the bolt has pulled it all together - it just stops it falling apart when undone.
My first port of call would be to check the hanger alignment (with a tool).
Hmmmm. The exploded view doesn't show any washer or spacer, just the tiny little C shaped circlip which is present (just visible in my 3rd picture).
I think it's definitely some kind of spacing issue. It's running perfectly now, exactly as you'd expect. I thought there might be something missing from the hub but people stopped fitting spacers and easily lost end caps from hubs years ago didn't they?
If I can find a washer that fits better I'll just leave it in.
I don't see how a spacer should make a difference, it would be the same as adjusting your limit screw and cable tension
I don’t see how a spacer should make a difference, it would be the same as adjusting your limit screw and cable tension
Because the mech is literally too far over by a couple of mm. With no cable tension and no limit screw it won't drop onto the smallest sprocket.
The washer has moved it outboard enough that I can use the smallest cog and gain enough space to use the barrel adjuster to dial it in.
My first port of call would be to check the hanger alignment (with a tool).
Seconded.
you might find that your spacer is making up for an inward bend of the hanger
Have you tried setting it up afresh? Possibly just poorly set up in the first place. If adding the washer makes it shift right, you ought to be able to get the same outcome with normal adjustments to the limit screws and cable tension.
Edit: too slow!
The first thing I did was remove the cable, blast the outer with GT85, fit a new inner and start from scratch.
If adding the washer makes it shift right, you ought to be able to get the same outcome with normal adjustments to the limit screws and cable tension.
That's the problem. Even with zero tension and no limit screw it doesn't sit in the right place. It's too far inboard.
I don't have the massive hanger tool but I'll find something to check it with. To my eyeballs everything is bang on apart from the starting position of the derailleur itself.
I'll get back to it in a bit.
Well I'm not sure what the problem is but I've fixed it. I drilled a a 10mm hole in a washer and bolted it in there. Then I went for a spin around the mountainous streets of Sheffield and it's running perfectly. Should have looked at it ages ago!
What are the hubs? Wondering if the end cap isn't fully seated, or if it's a threaded hub assembly whether it's torqued up correctly. Does the hub locate in the dropout easily?
Other than that you'd have to assume slightly bent hanger.
Hunt Endurowide wheels. Bike is a Privateer 141. I wasn't impressed with the build out of the box to be honest (chain was too long amongst other things) so I was prepared for there to be something to be missing from the drivetrain.
The wheels usually go in and out no bother but I didn't check them today. I'll have a look tomorrow night.
Shimano dropout spec is 7mm to 7.5mm thick at the hanger for a conventional qr axle (without digging not sure what the number is for a through axle but it will equate to something similar in terms of derailleur mounting face distance from end of cassette). I make steel dropouts which are sometimes only 5 or 6mm thick, and I then need to add a washer or two like you describe. If the dropout is too thin, then you almost run out of spring tension to reach the limit screw, so spacing it out fixes that by moving it a little further into the spring stroke and increasing tension.
i had to space out my mech on my empire, exactly as above, for it to work properly.
Only one mech mind. other derailleurs worked perfectly ?? i put it down to combined opposites of tolerances and its no bother to have a wee spacer to make it work.
Perhaps just an issue with parts being out of spec as others have mentioned. I'm not sure how far the limit screws usually allow a mech to move past the end of the cassette in a normal setup.
I took the rear wheel out before work this morning. End caps are snug, nothing missing.
I might try to find a washer that's a tiny bit thicker so I can sit further in the adjustment range rather than right at the bottom end.
Now I just have to find and silence the mega creak it's developed. It's groaning like a haunted staircase.
I never had problems like this with my Geometron (R.I.P) That was such a quality bit of kit.
Hanger looks like it flares outboard
Hanger looks like it flares outboard
If it did surely that would help the case, effectively spacing the mech further out.
Since it needs a washer to space it out, and is all working now, I'm going with optical illusion.
Good point well made
Anyway, I took the rear mech off and the bolt has a lot of play in it. The plastic spacer on the back is very loose and floppy
Coming back to this, mine was the same when i took it off to replace a mech hanger and had the same thought it couldn't be right but could find no evidence there was anything missing or it was broken in some way. All worked fine when back together
I've never got to the bottom of a similar issue with an 11 speed SLX rear mech on my Cotic Flare. Brand new mech, brand new frame with straight hanger (as far as I could check), but it's just never shifted properly. I could set the high limit screw ang get it to shift perfectly up the block, but then never get it back to the bottom without winding a load of cable tension off. I've tried countless times, perhaps I've got the same issue...
In any case, I gave up and ordered a new Deore mech.
Nobody's going to mention the lack of a ferrule on the gear cable? Obviously won't affect the shifting, but might help prevent a bloodied thumb/finger/eye in the future...
Check the inner cage?
Ive had 3 crack on slx now and come to the conclusion they're made of cheese and a few quid more for XT is worth it.
My mate's SLX ripped itself to bits when changing nut under any load. Ended a point to point ride for him - had to limp home on the roads single speed. Still beat us though.
Chain seems a little close to the frame compared to my set up, I can see a bit more of my endcap, maybe because it's clean and silver being a Hope pro4, that would explain it, are the end caps definitely the correct model or orientation, cos with the cable undone and limit screw out it should be too eager if anything to drop onto the small cog, it's very strange.
dhague, surely you mean a cable end cap or crimp, ferrule goes on the outer, maybe it's got superglue on the end to stop fraying, or they've just ran out.
Some bikes/dropouts/cassette/hub combos are out of shimano specs, I have had to use a washer to space a mech out before.