Correct Rear Mech Size

[aerobrain]

Hi

After my first crash I've sheared a bolt off my rear mech and decided it's a sign to get myself an upgrade!!

Plan is to go for a 105 or if I can find a good enough offer maybe Ultegra. Anyway, I've currently got a 50/34 compact double chainset and a 12-25 cassette however I'm doing some hilly sportives next year so when I replace this cassette it is likely to be for a 12-28 or 11-28. Would the Medium cage cover both of these? Would it just be that the shifting while on the 12-25 won;t be quite as crisp or is there a fundamental reason not to use the medium cage until I change the cassette?

Cheers

Lee

 

[T.M.H.N.E.T]

The short cage mech covers both of those Short takes a max 30 - med max 32

5701 series

 

[aerobrain]

The short cage mech covers both of those Short takes a max 30 - med max 32

5701 series

Cool, there's a few Ultegra ones on eBay for a bit more money. Do you think a brand new 105 or a second hand Ultegra would be the better option? Obviously it'll depend on condition but just wondering if there's much difference between them and if it's worth taking the risk second hand.

Cheers

 

[T.M.H.N.E.T]

Just upgrading the rear mech isn't going to be a useful spend, the differences in the full groupsets 105/ultegra are miniscule anyway.

Personally I'd buy new for a relatively cheap mech/chain/cassette. Shifters on the otherhand if I ever required, I'd be considering S/H!

 

[aerobrain]

Just upgrading the rear mech isn't going to be a useful spend, the differences in the full groupsets 105/ultegra are miniscule anyway.

Personally I'd buy new for a relatively cheap mech/chain/cassette. Shifters on the otherhand if I ever required, I'd be considering S/H!

Cool cheers, 105 is only £30 on Chainreaction so pretty cheap. Shifters would be the next piece in the puzzle!!

 

[T.M.H.N.E.T]

Cool cheers, 105 is only £30 on Chainreaction so pretty cheap. Shifters would be the next piece in the puzzle!!

Part of me wants to ask why

 

[aerobrain]

Part of me wants to ask why

Just want to upgrade really, never been 100% happy with the Tiagra and heard good things about the 105 groupset. The rear mech's just been a bit forced with the old one breaking.

Do you have any recommendations for cables?! Are the standard Shimano ones OK or would you go for a different make?

 

[T.M.H.N.E.T]

Most likely very much the same

 

[User6179]

The new 10 speed tiagra rear mech looks the same design as 6700 ultegra , think you need medium cage if you go for 11or12-28 cassette as you have a compact crank .

 

[aerobrain]

Got the short cage in the end, Shimano web site has it down as the right one for a double chainset and capacity seems right from the equations I've seen.

Now just need to fit it :-/

 

[HLaB]

Got the short cage in the end, Shimano web site has it down as the right one for a double chainset and capacity seems right from the equations I've seen.

Now just need to fit it :-/

It'll fit, I use a 5700 105 short cage derailleur with an 11-28 cassette in the summer (its a 11-26 on my winter wheels).