12-30 cassette with a 105 short cage rear mech ok or not?

[oldgreyandslow]

I have an 11-28 rear cassette at the moment and see you can get a 12-30 ultegra now, will this be ok with my 105 rear mech compact set up?

 

[RebornBumbler]

According to this page:
http://www.chainreactioncycles.com/shimano-105-5701-10-speed-rear-mech/rp-prod85966

Yes

 

[oldgreyandslow]

Thanks, my 105 rear mech is older than this but hopefully will be ok I will order the cassette and give it a try

 

[potsy]

I did the same a few weeks back and it works fine, think it depends on bike too.

 

[slowmotion]

Which chainrings do you have? You need to check the total tooth capacity.

 

[montage]

53-39, 12-30 works fine for me, no need to adjust anything. I use ultegra short cage

 

[raleighnut]

Check chain length when fitted, Big to Big rings +2 links at least, though not through rear shifter to check chain is long enough.

 

[Kies]

OP - yes you will. I fitted one to my Defy 1 with an ultegra chain. Works well, and i'm using more of the cogs. Has really helped with spinning on hills

 

[Mattonsea]

As everyone else , I did the same a few months ago no problem here. Now I look slightly reasonable going up hill.

 

[oldgreyandslow]

I fitted the cassette, got the chain length right but indexing is not at all good. If I adjust the tension at the low end as in the instructions, large chainring 2nd and 3rd rear cogs etc I get it to change fine but then when on the small chainring and larger rear cogs it won't shift cleanly from 4th largest upwards. If I adjust the tension to get these right it screws up the change on the smaller sprockets.

Is it just a case of the rear mech not being as accommodating as the newer ones or am I missing something?

 

[Kies]

I had mine done by the lbs ... Nothing else changed (chain + cassette) so i'm guessing it's just adjustments required

 

[RecordAceFromNew]

I fitted the cassette, got the chain length right but indexing is not at all good. If I adjust the tension at the low end as in the instructions, large chainring 2nd and 3rd rear cogs etc I get it to change fine but then when on the small chainring and larger rear cogs it won't shift cleanly from 4th largest upwards. If I adjust the tension to get these right it screws up the change on the smaller sprockets.

Is it just a case of the rear mech not being as accommodating as the newer ones or am I missing something?

Not sure which 105 model you have, but have you ensured the B screw is squarely on the hanger tab, and the cable is clamped correctly? For RD5600 e.g. see this.

 

[oldgreyandslow]

Not sure which 105 model you have, but have you ensured the B screw is squarely on the hanger tab, and the cable is clamped correctly? For RD5600 e.g. see this.

Thanks, I had those instructions, I am pretty sure the b screw is fine but will pull the cable through the clamp a bit more to give some more adjustment range on the tensioner
Cheers

 

[JasonHolder]

Thanks, I had those instructions, I am pretty sure the b screw is fine but will pull the cable through the clamp a bit more to give some more adjustment range on the tensioner
Cheers

Lube and flex your cables. Then re adjust... Particularly the bend from Frame to derailer. Gets stiff bent and dirty..

 

[oldgreyandslow]

Thanks all, sorted. I slackened and pulled through a bit more cable, set the B screw a bit better, lubed the mech etc and readjusted as per the Shimano instructions, just been for a 10 mile shake down ride and it all seems fine.