Having to replace Cassette after only 500 miles Cube Touring Pro 625

[mrpie]

Hi guys, bought a new Cube Touring Pro last July and have since used it to commute to work twice a week for a total of 44 miles per week give or take. Some weeks i just go to the office once. I hadn't owned a bike in donkeys years so had to relearn about maintenance. I had a bit of chain slippage so went to a bike shop who said the hanger is bent ( i did accidently drop it) so had that swapped and it seemed fine until it started slipping on heavy load or when setting off. Basically i couldn't pedal when off the seat so had to sit on the seat and it would be fine.

I took the bike to leisure lakes as i had an issue with the crappy 3 bracket chain guard bracket which they sorted and i also mentioned slippage on heavy load. They confirmed that the casette was loose and had tightened it but the smallest cog was worn out and the entire cassette needed replacing.

My question is, is it normal to have to replace the cassette after about only 500-600, the mechanic said this is pretty normal on ebikes as that gear gets used the most? All gears are fine at this point apart from the small cog so i could be fine without as i find the second smallest to be enough for my needs. Casette is a Sunrace CSM58 11-51T which i'm having difficulty trying to source to replace for the near future, if anyone else had recommendations on another casette that would be appreciated.

 

[saneagle]

Hi guys, bought a new Cube Touring Pro last July and have since used it to commute to work twice a week for a total of 44 miles per week give or take. Some weeks i just go to the office once. I hadn't owned a bike in donkeys years so had to relearn about maintenance. I had a bit of chain slippage so went to a bike shop who said the hanger is bent ( i did accidently drop it) so had that swapped and it seemed fine until it started slipping on heavy load or when setting off. Basically i couldn't pedal when off the seat so had to sit on the seat and it would be fine.

I took the bike to leisure lakes as i had an issue with the crappy 3 bracket chain guard bracket which they sorted and i also mentioned slippage on heavy load. They confirmed that the casette was loose and had tightened it but the smallest cog was worn out and the entire cassette needed replacing.

My question is, is it normal to have to replace the cassette after about only 500-600, the mechanic said this is pretty normal on ebikes as that gear gets used the most? All gears are fine at this point apart from the small cog so i could be fine without as i find the second smallest to be enough for my needs. Casette is a Sunrace CSM58 11-51T which i'm having difficulty trying to source to replace for the near future, if anyone else had recommendations on another casette that would be appreciated.

The problem is that cycle shops like to sell you stuff. The different cogs in the cassette have different teeth. Some teeth are like sharks teeth, some are like your front teeth, and others can be all sorts of weird shapes. Also note that the teeth are different at different positions around the cog. That's all to aid shifting. The only way to know if your cassette is worn is to compare it with a picture of a brand new one of the same type. Check carefully and thoroughly to get an understanding of the teeth shape.

Personally, I think it would be unusual to wear that quickly on a middle gear. Check that there's not a small stone or bit of twig stuck between the gears.

A bent derailleur wouldn’t cause slippage. Instead all gears would be affected, and you would notice that your shifting wasn't accurate. Most derailleurs are not straight. Anyway, even if it were bent, you could use the adjusters to get accurate shifting and no slipping unless it'sreally bent. I guess they charged you for straightening it.

One thing I don't get. They said that your top gear was worn, but you had slipping when starting off. We're you trying to start in top gear?

Slipping in top gear is often because the chain is too long or the B-screw is not set correctly.

Maybe you can't find it because you wrote the number as 58, when it's actually S8. There are loads on Ebay and Aliexpress.

 

[soundwave]

loose cassette and dirty grinding paste on the chain is the problem why i keep mine super clean all the time and replace it at 0.5 rather than 1.

you need a chain tool to see how stretched it is because if you keep getting the bike shop to sort it will cost a fortune in labor costs.

 

[matthewslack]

Not normal, but can happen with lower quality components and certain riding styles. Also as @soundwave mentions, cleanliness and replacing chain before too far gone is essential, as is lubrication.

Once you are fixed, get a proper chain wear measurement tool, one where you can read off the % elongation, not just a cheap one that only says yes or no, and keep an eye on it.

I had one dodgy cassette that only lasted 1,000 miles, but it was a cheap piece of wannabe start-up crap brand selling rubbish. Proper Shimano 11 speed is lasting over 5,000 miles with my riding style.

Having said all that, if you ride in top gear all the time on maximum assist, with a high torque motor, then you are likely to wear out that top gear fairly quickly.

Edit:

I use Shimano M5100 11 speed 11-51. Never paid more than £49.99 for one.

 

[mrpie]

I've been cleaning the bike thoroughly (cassette and chain) every 2-3 weeks and if its particularly dirty i'll clean it over the weekend. Chain is also removed and cleaned by submerging into a degreaser.

I have bought a bunch of tools in the last few months, chain stretch checker too and so far its good. I have a feeling i might have accelerated its wear by not probably shifting well and also shifting under load. I've now got a handle on that, maybe its just a costly mistake for now?

Check carefully and thoroughly to get an understanding of the teeth shape.

Personally, I think it would be unusual to wear that quickly on a middle gear. Check that there's not a small stone or bit of twig stuck between the gears.

A bent derailleur wouldn’t cause slippage. Instead all gears would be affected, and you would notice that your shifting wasn't accurate. Most derailleurs are not straight. Anyway, even if it were bent, you could use the adjusters to get accurate shifting and no slipping unless it'sreally bent. I guess they charged you for straightening it.

Maybe you can't find it because you wrote the number as 58, when it's actually S8. There are loads on Ebay and Aliexpress.

One thing I don't get. They said that your top gear was worn, but you had slipping when starting off. We're you trying to start in top gear?

Slipping in top gear is often because the chain is too long or the B-screw is not set correctly.

when i dropped the bike it was slipping on all so i believe it was a bent hangar. It actually fell a second time and had an issue with it slipping in a middle cog and no amount of tuning was sorting it so i bought a hangar myself and replaced it which fixed the problem.

I was contemplating buying a straightening tool as a heavy ebike falling is probably gonna bend the hangar, even if its not possible to see with the naked eye. Thanks again for checking the model number, i was copying it direct from a spec website who listed it as 58. I'm still using the same chain that came with the bike, i'll check the derailleur manual and see what it specifies for chain length.

loose cassette and dirty grinding paste on the chain is the problem why i keep mine super clean all the time and replace it at 0.5 rather than 1.

you need a chain tool to see how stretched it is because if you keep getting the bike shop to sort it will cost a fortune in labor costs.

I have bought one and last i checked the tool (a month or so ago) the tool wasn't slipping through the chain, will check it again though. I'd like to say i'm mechanically inclined, have worked on cars before just not on bikes lol didn't want to screw up a new bike but now that i've had it for some time i'm happy to do the work myself. I've been using wet lube which would no doubt pick up more dirt from the road, maybe i should switch to dry and just reapply it more often?

I use Shimano M5100 11 speed 11-51. Never paid more than £49.99 for one.

Cheers for that i'll definitely look into this one as its going to need replacing sooner or later. Would like to keep the theme black on the bike though lol

 

[soundwave]

problem is with these bikes in this price range the wheels and group set suffer from crap components from the start.

seen plenty of shitmano wheel hubs being destroyed in days or weeks from brand new off the show room floor.

 

[matthewslack]

When you say 'its good', is that 0.5% or less, or not quite 0.75%? Some tools only check 0.75 and 1%, which is too late.

 

[guerney]

I have a feeling i might have accelerated its wear by not probably shifting well and also shifting under load

Didn't @Woosh say a couple of weeks ago gear sensors are unnecessary on torque sensing mid-motored bikes? If the OP is only getting 500 miles from his cassette, perhaps they are? With the gear sensor on my cadence sensing mid-drive, I got 3,986 km/2,476.79 miles from my last 8 speed £15.50 SRAM 8 Speed "Cassette 11-32T CS PG-850 Silver, 00.0000.200.396", despite using high motor power all the time. I simply shift gear under power while continuing to pedal, sensor detects gear shift and cuts motor power then engages power again after a set short period of time, which works perfectly unless I'm changing to a low gear in heavy rain while going up steep hills - gear sensor power cutoff works perfectly when ascending the same hills in dry weather, also works perfectly on flat roads.

You can enjoy listening to the sound of my perfect snappy gear changes, along with other stuff, as I ascend this hill (FF to 23 seconds):

 

[AndyBike]

Usually a cassette will last 3000-4000km, you can extend the life of the cassette by changing the chain regularly, theres a handy little tool that shows when its stretched* beyond its lifespan. If its not changed when this happens, the chain and cassette 'marry' together, and once that happens, even a new chain will slip on the old cassette



Chain Shimano CN-M6100 which retails at £20 which is a fair price really. Its a fairly good quality chain, and its nickle plated so is resistant to rusting if you dont keep on top of maintenance(Something we're all guilty of at times)





Mech alignment is critical, any shop should be able to sort that for you for a few quid,it is actually normal for a mech hanger to take a knock occasionally,no matter what bike it is, its just one of those things but easily sorted and as to the worn bottom cog, that seems a bit suspect to me them asking you to replace the whole thing. I'd just go the cog up and not bother replacing anything, though depending on the cassette thats on it, if you go to a bike charity recyclers, you can pick up a replacement(or a bag of them) for a quid or two. Shop sounds like its trying to pull a fast one.



So changing the chain, keeping it lubed and importantly keeping the drivetrain clean** will significantly extend the life of the system.

** Chain cleaning.
You can get a thing called a 'quick link' this allows the chain to be split without using a chain splitter, though it is very beneficial to buy a set of quick link pliers(yes i know, something else to buy) Its one of the better tools to own and you can get one for under a tenner) as sometimes getting the split link to open can be difficult as hell(and it closes them too)

When I clean my chain, i put the entire thing in a 2ltr coke bottle with some thinners, and give it a damn good shaking, then wash that off in a basin of hot soapy water, before rinsing in clean water, drying off and i use a hair drier to blast off any water left inside the rollers.
If you look about the house you will usually find a cupboard full of towels and sheets that appear to have been stored there, just ready for the job of wiping excess oil/dirt/lube off of bike chains(or anything)

Same goes for the cassette, keep that clean and free of any oily grit
Then relube, then wipe off the excess lube and refit

 

[guerney]

I should add, I got 3,986 km/2,476.79 miles from my last cassette, without any cleaning whatsoever - I only clean the rest of the bike when I replace the chain, and the last time I did that the chain was stretched/worn to the 0.75% mark. I also never clean the chain, I simply chuck over more Hypoid 90 (@saneagle and @Nealh's favourite chain lube). My chains and cassetes are cheap, basic 8 speed SRAM and KMC X8, so quite honestly I really don't care - the only reason I've bothered to keep track is because of @matthewslack's thread about chain wear measurements.

Feast your eyes, clean chain anal types suffering from OCD:

 

[saneagle]

Didn't @Woosh say a couple of weeks ago gear sensors are unnecessary on torque sensing mid-motored bikes? If the OP is only getting 500 miles from his cassette, perhaps they are? With the gear sensor on my cadence sensing mid-drive, I got 3,986 km/2,476.79 miles from my last 8 speed £15.50 SRAM 8 Speed "Cassette 11-32T CS PG-850 Silver, 00.0000.200.396", despite using high motor power all the time. I simply shift gear under power while continuing to pedal, sensor detects gear shift and cuts motor power then engages power again after a set short period of time, which works perfectly unless I'm changing to a low gear in heavy rain while going up steep hills - gear sensor power cutoff works perfectly when ascending the same hills in dry weather, also works perfectly on flat roads.

We don't know that his cassette is worn. It's highly unlikely to be worn after 500 miles, even with abuse. He hasn't checked it. He hasn't shown any photo of wear either. Until the facts are established, you shouldn't try to draw any conclusions.

 

[guerney]

We don't know that his cassette is worn. It's highly unlikely to be worn after 500 miles, even with abuse. He hasn't checked it. He hasn't shown any photo of wear either. Until the facts are established, you shouldn't try to draw any conclusions.

True, he could have been swindled by those bike shop guys. Wouldn't surprise me, the 100+ year old owner of my local bike shop is a crook, everything he's ever sold me was trash.

 

[saneagle]

True, he could have been swindled by those bike shop guys. Wouldn't surprise me, the 100+ year old owner of my local bike shop is a crook, everything he's ever sold me was trash.

They normally point to the different shaped teeth on the cassette and say, "See, It's worn", and ignorant gullible owners accept it and the price of a new cassette. That's bread and butter for a bike shop, the same as the chain stretch tool and the derailleur hanger tool.

 

[Bonzo Banana]

We don't know that his cassette is worn. It's highly unlikely to be worn after 500 miles, even with abuse. He hasn't checked it. He hasn't shown any photo of wear either. Until the facts are established, you shouldn't try to draw any conclusions.

I think if you are setting off in your highest gear with a mid-drive ebike of high torque after 500 miles the smallest cog on the cassette could be worn in my opinion. However even on the cheapest cassettes the 2 smallest cogs are loose so you can replace them without replacing the whole cassette. Maybe the ebike has poor high gearing so you are forced to use the smallest cassette cog most of the time in order to get to a good speed. I did a quick google for the model but unsure if I had the right one and they didn't state how many teeth on the crankset chainring. It could be low though forcing heavy use of the smallest cog on the cassette.

If you can't get one locally I find there are loads of individual cogs for cassettes on aliexpress and for higher speed cassettes which typically cost a lot more money replacing individual cogs on the cassette makes a lot more financial sense. As a heavier rider who is more of a grinder/masher of the gears I tend to wear down the smallest cogs more quickly because I am more comfortable with delivering higher power at a slower cadence.

 

[AndyBike]

I should add, I got 3,986 km/2,476.79 miles from my last cassette, without any cleaning whatsoever - I only clean the rest of the bike when I replace the chain, and the last time I did that the chain was stretched/worn to the 0.75% mark. I also never clean the chain, I simply chuck over more Hypoid 90 (@saneagle and @Nealh's favourite chain lube). My chains and cassetes are cheap, basic 8 speed SRAM and KMC X8, so quite honestly I really don't care - the only reason I've bothered to keep track is because of @matthewslack's thread about chain wear measurements.

Feast your eyes, clean chain anal types suffering from OCD:


View attachment 56300

Durty bu66er

Shields eyes from the horror. I'll have nightmares tonight.

 

[mrpie]

When you say 'its good', is that 0.5% or less, or not quite 0.75%? Some tools only check 0.75 and 1%, which is too late.

The checker i have only checks 0.75 and 1%. I'll grab one that has 0.5, checked it a few minutes ago and still doesn't slip through at 0.75. Here's a picture;

I think if you are setting off in your highest gear with a mid-drive ebike of high torque after 500 miles the smallest cog on the cassette could be worn in my opinion. However even on the cheapest cassettes the 2 smallest cogs are loose so you can replace them without replacing the whole cassette.

Usually a cassette will last 3000-4000km, you can extend the life of the cassette by changing the chain regularly, theres a handy little tool that shows when its stretched* beyond its lifespan. If its not changed when this happens, the chain and cassette 'marry' together, and once that happens, even a new chain will slip on the old cassette



Chain Shimano CN-M6100 which retails at £20 which is a fair price really. Its a fairly good quality chain, and its nickle plated so is resistant to rusting if you dont keep on top of maintenance(Something we're all guilty of at times)





Mech alignment is critical, any shop should be able to sort that for you for a few quid,it is actually normal for a mech hanger to take a knock occasionally,no matter what bike it is, its just one of those things but easily sorted and as to the worn bottom cog, that seems a bit suspect to me them asking you to replace the whole thing. I'd just go the cog up and not bother replacing anything, though depending on the cassette thats on it, if you go to a bike charity recyclers, you can pick up a replacement(or a bag of them) for a quid or two. Shop sounds like its trying to pull a fast one.



So changing the chain, keeping it lubed and importantly keeping the drivetrain clean** will significantly extend the life of the system.

** Chain cleaning.
You can get a thing called a 'quick link' this allows the chain to be split without using a chain splitter, though it is very beneficial to buy a set of quick link pliers(yes i know, something else to buy) Its one of the better tools to own and you can get one for under a tenner) as sometimes getting the split link to open can be difficult as hell(and it closes them too)

When I clean my chain, i put the entire thing in a 2ltr coke bottle with some thinners, and give it a damn good shaking, then wash that off in a basin of hot soapy water, before rinsing in clean water, drying off and i use a hair drier to blast off any water left inside the rollers.
If you look about the house you will usually find a cupboard full of towels and sheets that appear to have been stored there, just ready for the job of wiping excess oil/dirt/lube off of bike chains(or anything)

Same goes for the cassette, keep that clean and free of any oily grit
Then relube, then wipe off the excess lube and refit

Thanks for that info, as my previous post i do a thorough clean, bike came with a KMC X11 chain and i bought some extra chain links so i might buy another one, i use a glass jar and pop some degreaser and shake it up which removes all that old lube. I never wiped the 'excess' and just left it as it so thanks for the tip on that.

We don't know that his cassette is worn. It's highly unlikely to be worn after 500 miles, even with abuse. He hasn't checked it. He hasn't shown any photo of wear either. Until the facts are established, you shouldn't try to draw any conclusions.

I'll try and grab a clear picture of the cassette tomorrow providing weather is good for cleaning

 

[guerney]

The checker i have only checks 0.75 and 1%. I'll grab one that has 0.5, checked it a few minutes ago and still doesn't slip through at 0.75

Which chain lubricant do you use? After my most recent cassette and chain replacements, both brand new, gears slipped initially, but stopped with liberal application of Hypoid 90. My KMC X8 chains arrive coated in wax, Hypoid 90 makes them more supple.

 

[mrpie]

Which chain lubricant do you use? After my most recent cassette and chain replacements, both brand new, gears slipped initially, but stopped with liberal application of Hypoid 90.

Muc off wet lube. Having a look at the Hypoid 90, it seems to be actual oil for a motorbike? Do people actually use this to lube bike chains?!

 

[guerney]

Muc off wet lube. I'll look into that Hypoid 90 but i dont know if that'll stop the current issue with the skipping on the small cog?

IMHO that sounds like your derailleur needs adjustment via the screws. There are oodles of Youtube videos showing how to do that - if that doesn't work, perhaps remove that small cog and upload detailed photos for the experts to inspect? I think it extremely unlikely that's worn after just 500 miles, even if you have been starting at high motor torque on the highest gear every time. Make sure chain tension is right for that top gear, too much slack could cause slipping. Also check your chain length is correct.

 

[mrpie]

IMHO that sounds like your derailleur needs adjustment via the screws. There are oodles of Youtube videos showing how to do that - if that doesn't work, perhaps remove that small cog and upload detailed photos for the experts to inspect? I think it extremely unlikely that's worn after just 500 miles, even if you have been starting at high motor torque on the highest gear every time.

Honestly thought i had, park tools videos have been a great learning tool. All gears are shifting fine when on a bike stand but it's a different matter when riding. I'll give it another check but if the bike shop couldn't fix the skipping even after tightening the casette. Their exact words were

'Tightened Cassettte as it was very loose. Gears Jumping under load on bottom cog. The rest seem fine, no battery with bike to test with motor on'

Surely they aren't devious enough to deliberately mess the tuning with the lowest cog on the chance i'd say yes to buying and having them replace an entire cassette?

I'll try my best to take some pictures tomorrow after cleaning, i don't have the tools (yet) to remove the cassette entirely.