Crank and cassette advice

[toastyhamster]

Have recently used the rubbish weather to do some bike maintenance, something I've sorely neglected to do.

My poor Specialized Allez really needs a complete drivetrain, however I'm a bit stuck on the setup the bike is currently on.

I've got a 50/34 FC-3550 Sora crank set coupled with an 8 speed cassette. Everything I read tells me that the crank set is only suitable for 9 speed, I can't even find an 8 speed version. I've had the bike about 10 years and I think it's a 2009, which also should make it a 9 speed.

The front big ring is wrecked, rear cassette is fine, gears are indexed, done over 2k miles on it with zero issues (despite crappy maintenance). I really just want to replace the crank set and the chain.

Have I got a mongrel and what's my best way forward?

[irc]

Replace the chainrings.

https://www.bikeparts.co.uk/products/shimano-fc-35...

While you are at it replaced the cassette. Cassette wear is not always visible. No point skimping for the cost of a 8 speed cassette.

https://www.halfords.com/cycling/bike-parts/gears-...

Loosening chainring bolts is easier with a decent tool


https://www.evanscycles.com/brand/fwe/chainring-bo...

As for the 9 speed/8 speed thing. The only difference in the chains is the 9 speed is fractionally wider. It should be OK Alternatively you can run a 9 speed chain on a. 8 speed cassette. The interior gap is the same. It's the sides that cary slight in thickness.

Edited by irc on Monday 31st July 15:35