Front Derailleur Replacement

[Crankpoet]

After my Carrera Subway was stolen I became the proud (?) owner of a 'bitsa' special with an early Giant FCR frame and forks but a wide variety of components apart from that (including a 28" front wheel and 700c rear!). My issue is that it has a front derailleur which is very rough in appearance connected to SRAM gripshift gearshifter.

I want to have a Shimano front shifter and derailleur but have no idea what to get - I have a triple chainset on the front which claims to be a Suntour, the rear cassette is an anonymous 7 speed. Do I have to change the whole drivetrain - which sounds expensive or can I just change the shifter and front derailleur? What would be the compatible Shimano components (it looks like 52-42-30 chainrings) ?

The rear derailleur is a newish Shimano Altus mated to an old Shimano trigger shifter (very slow slightly unreliable changing).

All help and suggestions gratefully accepted - I really don't want to spend a lot of money as the bike only cost me £70!

 

[raleighnut]

Basic Shimano front mechs are pretty good but you need to match them to your downtube diameter but it sounds like you could do with changing inner cables as well, only a couple of quid.

 

[Crankpoet]

Thanks for that - so any Shimano front mech will do as long as I get the downtube diameter and it is for a triple chainset, I appreciate the help.

 

[raleighnut]

Thanks for that - so any Shimano front mech will do as long as I get the downtube diameter and it is for a triple chainset, I appreciate the help.

Its got to be a road type in order to cope with a 52 tooth outer ring as well a 'compact' (44 tooth on MTB) won't work.(the shifter arm should match the radius of the outer ring)

 

[KneesUp]

It will need to be for a triple as well I think - to have sufficient movement to cover all three rings.