Chain / cassette wear - help

[p3eps]

Help!

A few weeks ago my chain snapped. I popped a quick link in, and cycled home.
My Park Tools CC2 said the chain was about 0.25%, so I ordered a new one. The drivetrain had done around 1500 miles, so I figured this was acceptable.
I did try my LBS, who advised they were completely out of stock of chains, cassettes etc, so I got one from Amazon.
When it arrived, I chopped it to the same length as my old one and fitted.

The next ride, the chain slipped a few times. I tried some micro adjusts, but it seemed that under load on some gears, the chain would slip. A quick google search, and the conclusion was my cassette was worn from the symptoms described.

The XX1 cassettes were out of stock everywhere in the UK, so I ended up ordering one from Europe. I went with the 10/52T one, as I’ve always had the intention of changing my chainring from 30T to 32T, and I thought the 10/52T would still give me a good bail out gear. It’s taken nearly 2 weeks to arrive, and now I have the pair of them side by side, I’m wondering if my cassette is actually worn at all.

The brand new one has the same ‘sharp’ stump little teeth, that I thought were worn on my old one. The rainbow colouring has worn off on my most frequently used gears, but to be honest it did that after a few weeks.

I’m now left thinking I’ve just spent over £350 on a new cassette that I don’t actually need yet. If this is the case (hopefully someone can advise from the photos?) then what is the skipping problem? My front chainring was pretty worn, so could it be that?

Next question... if I was to change from 30T front and 10/50T rear to a 32T front and 10/52T rear, should I be adding more links to my chain?

I ordered a second chain too, and was going to rotate them to try and save wear to my cassette. How often should these be rotated? Every 100 miles, or more, or less?!

Appreciate any help!

 

[lightning]

Fit the new cassette and try it.
lf it stops the chain from slipping, then your old cassette is obviously worn.

They don't always look worn, l had this with my 11 speed XT, fitted a new chain and it jumped in the high gear and in 4th gear from low.
l changed the cassette and it cured the problem. The original cassette looked fine.

Fortunately XT 11 speed cassettes are only £60.

lf your cassette turns out to be worn, why not refit the old chain and get some more mileage from it, then fit a new chain, new cassette and possibly a front chain ring.

Sure, you'd maybe have to buy a front chain ring as well (fit the new chain/cassette and try it first) but l bet that's a fraction of the price of a cassette.

The system may last another 1,000 miles. l
doubt the chain will become weaker to the point where it's more likely to break, someone please correct me if l am wrong.

 

[Barbara_Reed]

My bike shop reckoned that one chainring would see off two casettes and at least four chains. You know you can get a gauge to measure the wear on the gear teeth? And wipe the chain down after every 50 or so Kms helps.

 

[lightning]

My Race Face 30t front chain ring lasted 7,000 miles
That was about eight chains and three cassettes.

The replacement did 6,000 miles and still seemed OK but the LBS fitted a new one when l took the bike in for a suspension service.

After looking at the prices of the 12 speed SRAM kit on my new Ebike, l've cleaned the chain with a chain cleaner and re-oiled it twice already in the first month of owninership !!

 

[p3eps]

You can see a pretty big difference between the old and new chainring teeth!

 

[lightning]

Yes you can. But the old chain ring may still work fine.
Having said that, at the price of a chain ring l would probably replace it at that level of wear.
How many miles has it done?

 

[Barbara_Reed]

Sounds about right, then

My Race Face 30t front chain ring lasted 7,000 miles
That was about eight chains and three cassettes.

The replacement did 6,000 miles and still seemed OK but the LBS fitted a new one when l took the bike in for a suspension service.

After looking at the prices of the 12 speed SRAM kit on my new Ebike, l've cleaned the chain with a chain cleaner and re-oiled it twice already in the first month of owninership !!

 

[Gary]

Baffles me why anyone would shell out £350 for XX1 cassettes to run on an EMTB

 

[p3eps]

Baffles me why anyone would shell out £350 for XX1 cassettes to run on an EMTB

Cause I have more money than sense, and nothing better to spend it on just now.
You could argue a Levo SL is lightweight, and putting a GX or NX cassette on adds to that.

You’re usually very knowledgable of these things Gary... anything useful to add?

 

[Gary]

The (Shimano 105) cassette on my Emtb is lighter than an XX1 and cost £25
But that's partly because I don't need nearly as low a gear as 30x50 on any bike (but I'm not you)

I'm not interested in arguing. it's your money. Spend it as you see fit.

 

[p3eps]

The (Shimano 105) cassette on my Emtb is lighter than an XX1 and cost £25
But that's partly because I don't need nearly as low a gear as 30x50 on any bike (but I'm not you)

I'm not interested in arguing. it's your money. Spend it as you see fit.

We’ve been through this one several times before about what gears I use! I frequently use the 50T cog when doing long 20% climbs at Glentannar, Mount Keen etc.
I only ride with 25% assistance on an SL. It’s just a little boost, not a 400% eMTB.
I’m not as fit as I’d like to be either, but a winter of Zwift in lockdown has maybe helped with that a bit!

 

[Gary]

Yeah. like I said. I'm not you.

 

[p3eps]

Yeah. like I said. I'm not you.

Anyway... whether I use a 50 or 52T XX1 cassette isn’t the point of the post. Does the original one look worn beyond its best?

 

[Gary]

it's impossible to tell from simply eyeing it up.

It doesn't take much wear at all on a 10t sprocket for it to slip under load as there are only ever 4 teeth in contact with the chain.
Which is precicely why I think it's mental to even consider using these cassettes on Emtbs.

 

[Giff]

I’m not sure if it helps but I have just replaced all my drivetrain, cassette,chain and chainring.

....but it was skipping straight away. I had replaced the jockey wheels about 800kms ago and it seems that they had worn into the old chain. I had spares and it seems to have cured the problem.

I will be testing tomorrow.

 

[lightning]

When l bought my Ebike l looked at the cassette with the 50t big ring and laughed, "l will never use that" l said to myself.

Well, it turns out that l do use it, for technical sections when l can't go fast, and very steep climbs when l have no run up.