Unanswered How worn is this cassette?

[pgrbff]

My 12 year old saved up and bought himself a full suspension emtb. I have a new job, bike mechanic. I know next to nothing about bikes, I have a very bad back and haven't ridden for 30 years.
How worn is this cassette? It looks quite worn to me. The bike is 3 weeks old, regularly pressure washed and chain lubed with wax emulsion, we're in Italy and it's hot and dry. Done less than 500 km mainly on roads around town.

 

[salko]

This one looks preety good to me, maybe a bit wear marks on smaller cogs, but plenty of life in it.

 

[Mcharza]

Looks like a new

 

[steve_sordy]

I had to look really closely. The smaller rings have some burrs on them, but nothing to worry about. Ring Nos 5-7 (counting from the smallest) look the most worn in terms of elongation of the tooth, but if it is shifting OK, then I'd leave it. I'd be more concerned about the front ring.

By the way, it is never good to pressure wash your bike. The pressurised water can penetrate past seals and fill the bearings with water and crap. Seals also keep the water out of the stanchions on your fork, shock and seatpost. Use a bucket of soapy water, a brush and a watering can.

 

[pgrbff]

Aren't all the teeth supposed to be the same shape? An awful lot of them look triangular, not worn?

 

[steve_sordy]

Aren't all the teeth supposed to be the same shape? An awful lot of them look triangular, not worn?

The teeth are very carefully shaped to assist shifting gear to a higher or lower gear. Phd theses have been won on chain tooth design. If you look carefully, you will see shifting ramps carved into the sides of the teeth as well.

 

[flash]

Aren't all the teeth supposed to be the same shape? An awful lot of them look triangular, not worn?

Not on modern mountain bikes, no.

Gordon

 

[Richywalker64]

Looks like new to me

 

[aarfeldt]

‘Regularly pressure washed’

cassette is fine. Bearings are rusting.

- all the bearings

It's actually kind of annoying, to allways hear this rubbish.
As long as we don't know the pressure, the point is invalid.

My garden hose is "pressure washer"....but the pressure is so low, that no harm is done.

 

[pgrbff]

I agree it is probably better not to pressure wash but here in Italy where I think cycling is a far more popular sport, all the shops I have used do pressure wash. I find it hard to believe that a couple of minutes of pressure washing is any more detrimental than cycling for a couple of hours in the rain.

 

[pgrbff]

Can someone suggest some reading on shift technique with an e bike? I didn't know such a thing existed!

 

[NoPro]

Can someone suggest some reading on shift technique with an e bike? I didn't know such a thing existed!

try to keep your cadence between 70-90 rpm and reduce the power you put into the cranks when you shift.

 

[aarfeldt]

we don’t commonly call hose washing ‘pressure washing’

Well....I use Pressure Washer all the time.

It's a portable Kärcher unit with very low pressure...actually specific to use on eMTB's.
It will not harm any electrical parts or bearings.

And it's a Pressure Washer !

 

[steve_sordy]

Can someone suggest some reading on shift technique with an e bike? I didn't know such a thing existed!

As with regular cycling, just back off the leg pressure as you shift to a larger gear. Shifting to a smaller gear is less critical, but it is still good practice. It is so engrained in me that I cannot bring myself to shift under load. That practice normally works under all cadences and situations. It is worth practicing until it is automatic.

But sometimes I am in a situation where I am heading uphill and the hill is steeper than I thought and I desperately need to shift to a larger gear. But if I back off the power I will lose momentum; what to do? In that case I use the mode shift on my emtb to move to a higher power. That allows me to give a bit of a surge that then allows me to briefly back off the leg pressure and change gear. I then can down shift a mode. Simples.

 

[salko]

I agree it is probably better not to pressure wash but here in Italy where I think cycling is a far more popular sport, all the shops I have used do pressure wash. I find it hard to believe that a couple of minutes of pressure washing is any more detrimental than cycling for a couple of hours in the rain.

Its not how many minutes you pressure wash your bike, but where you point the pressurized jet. If you point it directly into the bearings or electronics components they could fail very soon.

 

[flash]

Well....I use Pressure Washer all the time.

It's a portable Kärcher unit with very low pressure...actually specific to use on eMTB's.
It will not harm any electrical parts or bearings.

And it's a Pressure Washer !

It's just a bit of common sense. I have one of the portable Karcher units and it's great. I also have unusually high water pressure at home. Enough that I could easily get water into a bearing or behind a seal, which is bad. I'm just careful that I don't spray at full force into a bearing or seal but along the wheel rims and under the saddle I let her rip.

I try not to get caught up in technicality's. Don't spray water with force at bearings or seals on your bike if you want to maximise their life.

Gordon

 

[jerry]

It's a portable Kärcher unit with very low pressure...actually specific to use on eMTB's.
It will not harm any electrical parts or bearings.

You just set the Karcher to the "EMTB" setting, and it automatically reduces pressure when pointing to bearings or electrical parts.

 

[jaggysnake]

must have a good job for a 12 year old , when i was 12 couldn't save up a pound

 

[pgrbff]

Your obviously doing ok now with a turbo levo. He sold all his old lego technics and other saleable toys on ebay, saved up Christmas and b'day money and a neighbour pays him to strip plaster off her newly aquired house. He is 12, 6' ish tall and best part of 100 kg. I did have to lend him the last bit as we didn't want him missing the summer. We're quite remote and 600 metres up, quite hilly, lets him get aboutband meet up with friends.

 

[Manc44]

Assuming 1 is biggest and 10 is smallest, sprockets 5 + 6 (and maybe 7) look worn to me but the rest don't.

 

[The EMF]

If that cassette looks worn to you I’ll give you my address and I’ll gladly take it off your hands ????