My 105 drive train is a mess

bikegangster

First I got a stretched chain so I'll have to get a new chain and a cassette. If I strain my pedaling too much, the chain will ping off the chainring. And my rear derailleur won't shift up from eighth gear onwards.

I'm thinking of getting a third party cassette from Miche Primato, a 12-27. And replace my current 11-32. Shimano doesn't have an exact 12-27 in their 105, 11-speed ranges which is a pain in the ass. Maybe in Dura-Ace but they're extremely expensive, I ain't spending that much for just a bloody cassette. I never use the 11 teeth and don't need the 32 teeth either. so a 12-27 is more suitable for my needs.

What do I need to change a cassette? Do I need a lockring and a chain whip? Could I buy any lockring or is there a specific lockring I have to get? I looked at some details on some lockrings and it only fits a 'HG' cassette. I can't tell if mine is a HG. My current cassette is from a 105 range either way. I already have a chain tool to remove and install chains so no need to buy it again.

Secondly, how do I fix my derailleur? The spring won't push the cage to the highest gear. I don't have to touch the limit screws, they're fine. Don't need to touch the barrel adjuster either.

Cheers.

shirley_basso

You could have worn out the chainrings, which are replaced with a torx key. That is a classic symptom.

I'd remove rear mech cable and start again from scratch.

Chain whip, cassette removal tool (yours is HG) And adjustable wrench. Cheaper to buy the toolkit. I bought the 18 piece 'bike hand' one from tredz and threw in the topeak chain measuring tool to take me over 30 to qualify for free postage and the 5er off.

bikegangster

Update: Job done.

Bought the tools and replacement parts. All of this cost me just over eighty quid. Changing the cassette the first time myself instead of paying a mechanic to do it. Its easy. I had to buy a new chain tool as my old chain tool only works with eight speed chains. And the Miche Primato cassette is missing one spacer and I had to take a spacer from the old cassette. All good. Also replaced the gear cable, it was dying. It was a pain in the ass digging out the worn out cable out of the shifter/brake lever but eventually did it and put in a new cable. Finally set up the derailleur again, and shifting is on point except the third gear, can't always shift up to it from second but I can shift down from fourth gear without issue.

shirley_basso

Good work.

Shame about the shifting - I assume you have checked rear hanger alignment?

Is the chainrings issue also resolved?

bikegangster

Chainring doesn't need to be touched. Thank goodness. They will be very expensive if I have to buy new ones! Like around fifty quid. The new chain doesn't fly off the chainring even under strain. The old chain does because its stretched so much there's less contact on the chainring and therefore the teeth can't grip the chain properly anymore. I never tried touching the hangar, I don't think the derailleur is bent. 11th gear (12 teeth) can't get accessed sometimes, I rarely use it anyway.

shirley_basso

That may be the lower limit adjustment screw?

Pretty satisfying sorting it yourself though, good work. Think of all the bike bits you can now buy with the money saved in mechanics fees.