Shimano replacement or upgrade.

chopchop

I want to change a few drivetrain components because they are tired, missed changes and slipping gears. Adjusting the mechs makes no difference, I think they've had their day. The rear mech looks a bit bashed so I'll change that as well.

What I have on the bike:

Rear mech RD-M591 Deore
Cassette is a CSHG50-9
Chain is a CNHG73

So, question is, should I just straight replace these or are there better alternatives or easy upgrades that will work with the rest of my setup?
Also, having priced up the bits, I have seen different options for the cassette (11-32 or 11-34) which one should I be looking for. I understand that the numbers indicate the number of teeth but could I use either one and what effect do they have?
What does 'long cage' refer to when choosing the mech?
If I were to straight replace the above, they come up as @£65 on CRC, anywhere cheaper?


Thanks in advance.

nicklouse

which cassette is up to you. do you want a lower gear?
cage length is all about your range of gears. See the FAQs.

chopchop

Cheers Nick. Having now looked at the FAQ, I realise I want a long cage as I have 3 rings up front.

I wouldn't mind as low a gear as possible as I'm still puffing uphills, so do I go for a 32 or 34?

I take it there wouldn't be any benefit choosing any different rear mech?

nicklouse

well a bigger cog will give a lower gear.

nothing wrong with Deore parts.

chopchop

Ah, thought the cogs would be the same size but with different teeth spacing- makes sense now!

I have a 34 on the bike so will straight swap and try to get fitter.

Anything else I should consider changing while the rear hub is in bits? bearings etc?