You don't need to be an 'investor' to invest in Singletrack: 6 days left: 95% of target - Find out more
Can I use a short cage mech with 11-32 cassette if single ring?
Have just bought my daughter a new cx bike that comes with a 36/46 chainset and 11-28 cassette.
I need to change the gearing to make the hills a bit easier (she is 12).
She won’t ever use the big ring (might actually remove it) so was thinking the easiest change is to replace the cassette with a 11-32. However, the 105 rear mech is short cage which I understand wouldn’t normally work with a 32 cassette but will it be ok on the basis that we will only be using a single ring?
Many thanks
probably. maybe need a longer B-screw to clear the 32 cog.
I think it should be ok. Used a short cage XTR BITD with a 30T big sprocket and it had a lot of clearance.
Sram not shimano, but my CX race bike has 2015 Sram Rival (so equivalent of 105 and their road groupset, not a "CX specific" variant) with a short cage rear mech. I've converted it to 1x11 and fitted an 11-32 and it works fine.
Excellent, many thanks.
Anyone know if I’ll be able to get away with using the single ring (will replace with a narrow wide) without a clutch mech or using a chain guide?
Yeah no problem. Even really short short cage mechs have ~30T capacity so 11-32 will be fine.
A 36T narrow/wide ring will be fine. The bigger n/ws really hang on to the chain. No need for a clutch mech or guide
Many thanks all.
The new bike is getting more expensive by the minute having to replace bits to make them child friendly!
From the first link on google:
http://www.wiggle.co.uk/shimano-105-rd-5700-rear-derailleur/
Shimano 105 RD-5700 Rear Derailleur
Short Cage
Maximum low sprocket 30T
Maximum front difference 16T, total capacity 34T
raced a season of CX with my above set up and a NW ring and never got close to losing the chain. I think Sram mechs have slightly tighter springs than Shimano, but as as rocketman says once you get to road/CX size rings there's a lot of teeth holding onto that chain.
lem. Even really short short cage mechs have ~30T capacity so 11-32 will be fine
Err you're not really understanding the 'capacity' thing here. Capacity is front chainring difference plus rear cassette difference, so 11-32 is 21 plus 50-34 is 16 which equals 37 total.
This has nothing to do with maximum rear sprocket size which isn't necessarily govererned by cage length.
The OP needs to look up the spec of his mech and see what the quoted maximum sprocket size is. If it was 11sp 105 for example, short cage is 28 and long cage 32.
Yes is the 11 speed 105.
Once I get the cassette I’ll try and adjust the rear mech to work by adjusting the B screw and if I can’t looks like I’ll be putting my hand in my pocket again.
Yes,I use the 11-32 with my cross bike and a short arm 105.
Even ran it with a 50/34 double though not recommended!
I am using a narrow wide but there is a trick with Shimano on tensioning the spring to replicate a clutch.
Absolute Black had it on there site but it is also on the Park website.
Had no chain drops at all!
Max
That's good to hear, will check out the spring tension on their site.
what PeterP said. It's all to do with two things:
- the max sprocket size for that mech, and
- the mech hanger length
Some bikes handle bigger cassettes no problem but hanger length means that it's not a universal truth. You need to try it and see. Tweaking the b-screw isn't fallible either - sure it gives you more clearance on the big sprocket but it also moves the jockey further away from all the other sprockets, so shifting deteriorates.
10sp, but got a short cage 105 mech running an 11-36 fine. The top jockey wheel offset means it clears the cassette as the cage goes forward. Wouldn't work the same with a double.
I don't know if 11sp mechs have a similar offset though
I run a 11-36 cassette with a 10 speed ultegra mech on my cx with a 46/36 front ring without any issues. So can't think 11-32 would be a problem
I would guess at it being fine , my long cage ultegra mech listed as 32t maximum but does work with a 40t xt cassette but as above some of that is bike dependant
If you have the bits try it
And despite the lack of clutch it was fine on honc but I have a narrow wide
In therory to much adjustment of the b screw limits the amount of chain on the cog but most never get a problem