Max sprocket issue

MrJim007

Hi all,
Have upgraded to a SRAM Force groupset and all is working lovely apart from it the rear mech wont budge onto the largest sproket. It is the short cage mech whick states a max 28T sprocket. I have one of these on as I will be struggling round the Yorkshire Dales come July and could do with all the help I can get!!
Im sure I have set the low limit screw as far as it will go but when looking from behind the jockey wheel isnt quite lining up with the outermost sprocket. If I budge the mech by hand it seems to give a little more which may do the trick but I cant get it out there via the cable!!
Any clues?
Cheers.

peteone

Is the B screw set correctly? This may issues getting into the 28.

47p2

28t is the maximum the short cage can cope with, if you are not shifting into 28 then either the derailleur stop screw needs adjusting or the cables need adjusting

MrJim007

Cheers for the replies.

Im going to have another go tonight once the kids are out of the way!!
Im pretty sure I have set the limit screw out at maximum which is whats confusing me, though i will check again.
Will also check the b-limit as well, although how does this cause problems with the cage travel outwards?

Ta.

peteone

My route of thinking is that if your shifting to all other gears bar 28 then the cable tension is probably set correctly, and if as you say you have the limit screw set correctly the b screw is the only other thing I can think of trying.

The b limit adjusts the vertical distance between the top jockey wheel and cassette. I'm thinking maybe if it's set too close to the 28 then it may not be able to pass it to engage the gear.

May be worth going though the sram setup video here. It's for red/force grouppo but and covers limit screws and b screw.

http://youtu.be/ZTOyxOPHoGc

simonj

1. B screw
2. Limit screw
3. Cable Length
4. Chain Length

2 & 3 - I would have thought would have been an issue before with a smaller cassette
4 - I presume you're trying small cog at front to big cog at back in which case it may be nothing to do with chain, but if you're tyring big to big you may be running out of chain

MrJim007

Thanks all,

Sorted now. Being a div again!! I set up the limit screws before putting on the chain and was finding it difficult to set the low limit whilst holding the mech in. Once I checked again I realised how far out I was with it, having turned the screw entirely the wrong way!! :oops: