I have a 2010 Salsa Casseroll that I use for commuting and towing the (not so) little one around. It runs Shimano 105 in 3×10 configuration, with a medium cage 105 rear mech. After seven years of use I finally got round to replacing chain, all three rings, cassette and cables. In the process, I went from a 12-28 cassette to an 11-32. No amount of fettling with cable tension (new cables and outers also) enables me to get the rear block in tune. I can either have the 32, or the 11, but never both without fiddling with the adjuster on the fly, which obviously isn’t great. Having exhausted all options, I was thinking that the 7 year old rear derailleur may have had it and the spring no longer has quite the strength to easily pull the chain all the way down to the 11 with any tension at all on the gear cable.

However, in the process of scouting for a new medium cage 10sp 105 or ultegra mech, I found comment on a couple of forums that in fact a standard road medium cage rear derailleur won’t handle the 32 sprocket due to the more extreme geometry. Does this hold true? If so, what are my options? As shimano produce an ultegra 11-32 cassette, I presumed they must also produce a mech to go with it? If not, as it’s a commuter / tourer, I’m happy to stick an XT mech on it instead. I assume this will work with 105 STI shifters? What speed do I need – I was under the impression that a 9sp MTB mech works better with 10sp roadie stuff, but not sure where I gleaned that pub fact.

Any thoughts on solutions gratefully received.

While we’re at it, any suggestions for where to get 9sp XT or 10sp 105/Ultegra stuff also much appreciated!

I’ve got a mate who is running mtb shifters with a soda rear mech and it runs perfectly. Not sure if 9 or 10 speed – I suspect 9 speed as it’s on an old Kona he uses for commuting in.

His comment was the mtb and road stuff just works perfectly together. I know nothing though about mixing the two. Got Rival on the racer and GX on the mtbs.

I would ring Madisons the Shimano importer, I’ve always found them really helpful with stuff like that.

9 speed mtb mech should work.

XT M772

Or

Deore M592

Why don’t you find the Shimano model number on the derailleur which might begin with RD, then Google the pdf, which will tell you the gear range it can cover?

Yep, Shimano 10sp struggles above 30t – except current (4700) Tiagra. The other solution is to use a Shimano 9sp mtb mech. We use a 9sp XT on the tandem, 3×10 with 11-34 cassette and 105 shifters.

Current generations of 105 seem to be a maximum 28t rear. The missus wanted a lower gear on her hybrid and I had to swap the sora rear mech on that for a deore one. Works fine.

To confuse matters, I’m using a 105 5700 med cage mech with an 11-34 cassette – it works perfectly, but a 34-46 double up front.
Indexing at one end but not the other on a cassette could be a slightly bent mech hanger, is this something you could check?

Why don’t you find the Shimano model number on the derailleur which might begin with RD, then Google the pdf, which will tell you the gear range it can cover?

Because just occasionally I remember that this forum is full of really helpful people who know a lot about this sort of stuff 😉

The rear hanger was slightly off (but oddly working fine on the 12-28 aside from tell-tale worn sprocket/chain crappiness). I’ll take a closer look at it as I might not have got it back perfectly, and failing that will look for a 9sp XT mech to replace the 105 with as it’s looking likely that it’s possibly more a “no” than a “yes” on 105/ultegra reliably working.

This is why I usually stick to MTB…

According to the specs a medium cage 10 speed 105 mech will http://www.wiggle.co.uk/shimano-105-rd-5701-rear-derailleur?sku=5360511993&source=igodigital

Except we don’t know exactly what mech you have – it’s good advice, check the number printed on the back and google it, you’ll find the official Shimano specs.

The rear hanger was slightly off (but oddly working fine on the 12-28 aside from tell-tale worn sprocket/chain crappiness).

It may just be that everything is a bit worn – and a slightly misaligned hanger doesn’t help, I suspect shifting over an 11-32 is slightly more challenging. Though in fact failing to shift isn’t usually the problem with a mech not designed for a big sprocket – normally it just won’t run right with the top jockey wheel running against the sprocket. Unless of course that is the issue you have, and that’s stopping it shifting properly. The question is, if you set it up in the recommended way with indexing adjusted on the second sprocket, does it shift OK up to the next to last sprocket and then just fail on the 32? Just one more thought – you don’t mention the limit screws, it might be worth adjusting those slightly.

This is why I usually stick to MTB…

In a way roadie stuff is simpler (at least up to 10), it was MTB which introduced the incompatibility in 10 speed.

Yep, Shimano 10sp struggles above 30t – except current (4700) Tiagra. The other solution is to use a Shimano 9sp mtb mech. We use a 9sp XT on the tandem, 3×10 with 11-34 cassette and 105 shifters.

With the health warning that the 4700 mech’ is the 11 speed pull ratio and not backward compatible to the older 105 and ultrega 10 speed stuff. It is rated to 34 teeth

Road bike mechanics is way simpler than mtb.

I would give the bike to someone who knows about checking the der hanger and setting b screws. If they cant get your present derailleur to work get a new one. Short cages where revised a little while ago to cover a bigger range but given your use a medium/long cage version may be more suitable.

http://www.wiggle.co.uk/shimano-105-rd-5701-rear-derailleur/

Hi

I can help!

I run a Fargo with 3 at the front and 10 at the back. It is an 11 36 out back and I have paired it with 10 speed 105 shifters and a medium cage 9 speed XT med cage rear mech.

It shifts brilliantly and there are no issues in setting it up. Looks cool too!

I hope this helps? My review of the bike is below.

http://singletrackworld.com/reviews/salsa-fargo/

Cheers

Sanny

The more I think about this more it sounds like a bent mech’ hanger

I suspect that the worn chain and sprockets was simply more tolerant of this and masked the problem

Cheers guys. As it doesn’t seem like the heresy I thought it might be to stick a XT mech on there I’ll go that way. It’s done an awful lot of miles for no replacement drivetrain, just usually in good weather (based in Oz), hence the longevity of the original components. When I took the old rings and cassette off I was surprised that it was still working at all given the state of them – an advert for letting it all wear out at the same rate I guess.

I’ll get it back on the stand and will get the hanger absolutely true as that seems to be at least potentially part of the issue. B-adjust screw was altered accordingly, as were the stop screws. Truth be told it was fine on the stand first time, but just wouldn’t behave under pressure of riding.

Another advantage for me of going XT is it means I’ll always have a spare if I prang the mech as my Soul is on 9sp XT

Did you not notice my link up there to a 10 speed roadie mech specced to work with a 32 sprocket? Assuming that’s where the problem is…

Did you not notice my link up there to a 10 speed roadie mech specced to work with a 32 sprocket? Assuming that’s where the problem is…

I did, thanks for looking into that. I’m inclined towards XT as it means I’ll then have two of the same type in my ‘fleet’ should I need a spare in a hurry. (The other is on my 26er Cotic Soul (3×9 XT) that will be prised out of my cold dead hands…)

I suspect the hanger on the Salsa is at least 50% of the issue, and as ampthill highlights: the old worn kit probably masked this to some extent. But, as the 105 on the bike is seven years and a lot of miles old it’s also probably partially responsible, and it does seem to have some play in it (too dark now to properly check the hanger).

Everyone always suspects the hanger, but in my experience, cable tensions in the last cable outer often as a result of the slightly deformed ferrule has been the commonest reason for shifting fine at one end and not the other.

XT nine speed will see your shifting fine. And it looks good 😉

in my experience, cable tensions in the last cable outer often as a result of the slightly deformed ferrule has been the commonest reason for shifting fine at one end and not the other.

This is a good point…

You said you replaced the cables OP, did that include the outers? And if so did you get the cuts nice and flush?

I use a dremel with a slitting disc to trim outers these days, as it gets a good flat neat cut without any crimping…

You said you replaced the cables OP, did that include the outers? And if so did you get the cuts nice and flush?

Yup, with swanky blue Jagwire ones 😀 Though now I’m going to sacrifice the bling gold nipple off the end of the cable when I cut it to replace the mech 🙁

Always make sure cuts are clean and opened fully afterwards. This is why I’ve been so puzzled by this problem, it’s been a very long time since I encountered a bike gearing issue that I couldn’t fix. Anyway, I guess we’ll see what the new XT mech does when it gets here…

It’s worth double checking the set up (from my own bitter experience of my dodgy spannering):

– Cable is definite clamped correctly at the mech (I’ve done this – clamp cable over top of bolt rather than under). It messed the gears up.
– If you’ve replaced the cable outers check the length of all the sections. Too long or short will give unreliable shifting.
– If your frame has any down tube barrel adjusters or cable routing bits under the BB check those. I had problems when the down tube bolt on barrel adjuster was a bit squint, too me ages to work it out but it also messed the gears up.
– Bent mech / hanger
– B tension adjustment, this will affect how it shifts onto the biggest sprocket

I’m using a 9 speed XT on my 10sp road / gnarmac bike. I have a 36t cassette though for child trailer towing duties and it all works perfectly so if you get no luck it’s a good option. They’re in stock at CRC amongst others.

Cheers Tomd. XT mech already winging its way from CRC to me. As it’s a shadow it’ll necessitate some trimming of cable and outer off the last loop. Being long cage it’ll also exaggerate any hanger squiffiness if I was in fact remiss in my last attempt at it. Cables and adjusters all fine, but will be re-re-checked when I install the mech.

Funny that 20 years of spannering MTBs has led me to be so stumped with my first serious road bike fettle that I’m sticking MTB componentry on it as a fix 😆