Looking for replacement cassette suggestions.

[beany_bot]

After fitting a new chain (first ever chain change) as it approach (but hadn't yet reached 0.75) I was very suprised to find the new chan slipping all over the place on the old cassette. Alas I need a new one.

The cassette on the bike (factory) is

Microshift CS-H092 9V 11/32 cassette
(11/13/15/17/19/21/24/28/32).

I can't seem to find a replacement for this anywhere like for like so could someone spec me a similar quality/value cassette? I guess ideally sticking with 11/32 as it is what I am used to. Don't mind getting a slightly better cassette but dont want to get a lesser quality one or vastly more expensive one. I looked at Sora cassettes but they dont seem to make an 11/32. It's a 9 speed and the bike is https://www.decathlon.co.uk/triban-rc-500-disc-road-bike-black-sora-id_8502354.html

Thanks!

 

[vickster]

Look at SRAM, compatible with Shimano 👍

Stocks look a little short but Halfords should have them for C&C
https://www.halfords.com/cycling/bi...ram-pg-950-9-speed-cassette-11-32-778225.html

 

[vickster]

Scrap that, cheaper on eBay from Parkers
https://www.ebay.co.uk/itm/Sram-PG9...289324?hash=item2d1117a02c:g:9lIAAOSwxmhfBfed

 

[beany_bot]

so, my commute is pretty flat, I spend 85% of my time in the 4 gear from the bottom, So I guess that would mean I want the same no. of teeth on that gear, just so it doesn't upset the apple cart. That would mean 17 teeth and going for the 11-34. Will my Sora rear mech handle 34T?

 

[vickster]

Why do you need 11-34 if you ride on the flat? 11-32 is already fine for hills
You could probably get away with fewer teeth

just get the sram one

 

[Cycleops]

Almost certainly, give it a try.

 

[beany_bot]

Because I usually sit in the same gear. So I want it to have the same No. of teeth. That is only the case in the 11-34 set.

 

[figbat]

It doesn't matter which gear has the right number of teeth - you just pick the gear that suits your speed and effort and go with it. Whether that is gear 4 or 5 or whatever is largely irrelevant.

 

[beany_bot]

It doesn't matter which gear has the right number of teeth - you just pick the gear that suits your speed and effort and go with it. Whether that is gear 4 or 5 or whatever is largely irrelevant.

I get that, but if im used to doing a set speed, at a set cadence, in a set gear. Makes sense to try and keep that one gear the same if poss? maybe im just overthinking.

 

[beany_bot]

There are two questions to answer regarding "Can my mech cope with this cassette". Both of them can be answered by checking the technical spec for the mech in question.

1. Capacity. Can my mech handle the size range. That's Big Chainring teeth + Biggest sprocket teeth - Little chainring teeth - smallest sprocket teeth. In your case that would be 50 + 34 - 34 - 11 = 39. Your mech will need a capacity of at least 39.
2. Max sprocket. What it says, what is the biggest sprocket your mech can handle. Specifically here can it handle 34?

Bear in mind these can sometimes be pushed a bit, and people often report going beyond what the tech docs say.

According to your Decathlon link you have "Shimano Sora R3000 9-speed rear derailleur with long screed" Huh? Screed? Never heard that term before. Presume that means the "GS" model. Anyway ...

You can find the technical spec here https://bike.shimano.com/en-EU/product/component/sora-r3000/RD-R3000-GS.html This tells us...

Low sprocket_Max. 34T
Total capacity 43T

So the answer is yes.

You can never have too low a bottom gear!

However, note that you may need another new chain. Because, presumably, you have cut the chain to the correct length for a 32T big sprocket. Going to 34 would need another couple of teethsworth of chain. Running a chain that's too short isn't really safe.

Thank you, lots of really helpfull information. Ill go with the 11-34 then. gives me a slightly easier hill climb and keeps my cruising gear the same. win win.

 

[roubaixtuesday]

Because I usually sit in the same gear.

This may be why it's worn out so quickly... Though you may find that running the new chain for a few miles might settle it in.

You need a fixie!

 

[roubaixtuesday]

Going to 34 would need another couple of teethsworth of chain.

Unlikely to be an issue - the chain only wraps around half the cassette, so that's one tooth different which is half a chain link. Need to test big/big before riding of course.

 

[beany_bot]

This may be why it's worn out so quickly... Though you may find that running the new chain for a few miles might settle it in.

You need a fixie!

No, they are all skipping like crazy! (except maybe the top two or three that I am rarely in).

My commute is flat, but I still take my bike to Arran and go on occasional weekend jaunts where it's not flat.

 

[beany_bot]

However, note that you may need another new chain. Because, presumably, you have cut the chain to the correct length for a 32T big sprocket. Going to 34 would need another couple of teethsworth of chain. Running a chain that's too short isn't really safe.

Damn, yes I cut the chain to the same length as the last one. 112 links including the connector link.

 

[beany_bot]

That's true - provided you do test it first. I may have overstated things a bit.

The risk is that you go into big-big and the chain is too short and nadgers the mech.

Stupid question incoming..... but who rides big-big? This doesnt make much sense to me. But sure I'll check.