Modernising a Specialized Sportrock retro mtb

[hedgey]

Re the above bike, I'd like to replace/ upgrade the 7 speed transmission and already have fitted a few parts that I had.

So its now sporting Shimano Rapidfire shifters and a Stronglight 46/36/26 triple chainset - to work with my 7 speed shimano cassette.

Id like to use the bike for touring so I'd like to get hold of a robust front and rear derailleur to work with the above.

I've looked at the shimano options but I'm totally confused as to which type/ speed/ model will work best...

... or wondered if there were other non Shimano options that might be an improvement and more durable/ reliable?

Any advice or recommendations of suitable parts/ part numbers would be really appreciated,

 

[lpretro1]

Most shimano 7 spd mtb front /rear derailleurs should work - acera is reasonable

 

[Smurfy]

The Chris Juden article is probably the best source of information. According to the mix and match table, all Shimano rear mechs (with the exception of old Dura-Ace) are interchangeable. This compatibility happens because the shift ratio of shimano rear mechs (ratio of cable pull to derailleur movement) is 1.7 in nearly all cases. See the table headed 'Shimano mechs'.

http://www.ctc.org.uk/cyclists-library/components/transmission-gears/derailleur-gears/shimergo

Differences in sprocket spacing (more sprockets means closer spacing) are achieved by varying cable pull at the shifter. A wise move on the part of shimano, as many people may wish to upgrade a rear mech, but few will want to use a 10 speed shifter with a 7 speed cassette, for example.

 

[hedgey]

Thanks for the replies - very useful.

I did also wonder if there was any kit that was more durable/ reliable/ robust than Shimano, that would work? I vaguely remember an alternative brand being mentioned somewhere?

 

[lpretro1]

Nothing wrong with Shimano - there are millions of bikes with all sorts on. SRAM is an alternative but is expensive and not necessarily better quality. As long as a bike is maintained well kit will go on for ages

 

[hedgey]

thanks for that... Shimano it is then,,,