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Rear Cassette Replacement

j.andersonj.anderson Posts: 7
edited May 2016 in The workshop
Hi, am new here. Hope I'm in the right place for this topic...

A few weeks ago the chain started to slip on the rear cassette of my mid-drive e-bike. The chain had done about 1200km so I had it replaced, but the slip is still present.

Although I cant see any major signs of wear on the rear cassette I think it may still need replacing. Does this sound about right?

The factory standard cassette is a Shimano 10 Speed HG50 11x36 teeth, though I am interested to know if a Shimano 10 speed 105 5700 with 12x25 teeth will be compatible, and if so how would it compare? (My rear mech is Deore if that helps).

Any advice would be much appreciated!

Posts

  • markhewitt1978markhewitt1978 Posts: 7,614
    j.anderson wrote:
    Hi, am new here. Hope I'm in the right place for this topic...

    A few weeks ago the chain started to slip on the rear cassette of my mid-drive e-bike. The chain had done about 1200km so I had it replaced, but the slip is still present.

    Although I cant see any major signs of wear on the rear cassette I think it may still need replacing. Does this sound about right?

    How do you mean slip? Cassette/chain wear will normally manifest itself with the likes of ghost shifting and it not going into gear correctly.

    You say you've replaced the chain, which is the most likely area for concern, so you can replace the cassette but 1,200km is a very short life for a cassette you would expect at least three times that.
    The factory standard cassette is a Shimano 10 Speed HG50 11x36 teeth, though I am interested to know if a Shimano 10 speed 105 5700 with 12x25 teeth will be compatible, and if so how would it compare? (My rear mech is Deore if that helps).

    You have a MTB derailleur, which shouldn't matter for these purposes just something to be aware of. AFAIK the 5700 12x25 should work, as should any Shimano 10 speed cassette. As for how it would compare, they are just gear ratios so, having a 25 instead of a 36 means your lowest gear will be much higher but you will benefit from a closer gap between the ratios.
  • Thanks for the reply,

    Sometimes I have to shift up or down a few times before the chain eventially settles on the sprocket. If I put load on the chain before it has settled it feels like the teeth haven't connected in the chain and I get a terrible grating!

    As for the gear ratios am I correct in thinking the 5700 will be smoother shifting, not as low a low gear and a higher high gear capable of higher speed?
  • dgunthordgunthor Posts: 644
    sould like your cable has stretched/bedded in (perfectly normal) and the gears need re adjusting - have a look on park tools website at gear adjustment
  • markhewitt1978markhewitt1978 Posts: 7,614
    j.anderson wrote:
    Thanks for the reply,

    Sometimes I have to shift up or down a few times before the chain eventially settles on the sprocket. If I put load on the chain before it has settled it feels like the teeth haven't connected in the chain and I get a terrible grating!

    As for the gear ratios am I correct in thinking the 5700 will be smoother shifting, not as low a low gear and a higher high gear capable of higher speed?

    Thing is that sort of thing can be worn chain, worn cassette or as said, cable stretch and misaligned gears. Might just need a few turns of the barrel adjuster to get it sorted. Most bike shops will be happy to look at it for you too.
  • davisdavis Posts: 2,505
    j.anderson wrote:
    Hi, am new here. Hope I'm in the right place for this topic...

    A few weeks ago the chain started to slip on the rear cassette of my mid-drive e-bike. The chain had done about 1200km so I had it replaced, but the slip is still present.

    Although I cant see any major signs of wear on the rear cassette I think it may still need replacing. Does this sound about right?

    The factory standard cassette is a Shimano 10 Speed HG50 11x36 teeth, though I am interested to know if a Shimano 10 speed 105 5700 with 12x25 teeth will be compatible, and if so how would it compare? (My rear mech is Deore if that helps).

    Any advice would be much appreciated!


    I would say that doing about 900 miles would result in cassette wear. The easy way to tell is to look at the cassette teeth. If they're all pointy then it's worn, and that's the end of it. Look here for more.

    Honestly if you do that many miles without replacing stuff then I would just go with the HG50 (and feel no guilt about it whatsoever). The cheaper cassettes are stronger and heavier. The 5700 cassette is closer ratio teeth, which will probably result in very slightly smoother shifting, but only if you shorten your chain. You'll also lose some of the range of the cassette.
    Sometimes parts break. Sometimes you crash. Sometimes it’s your fault.
  • The RookieThe Rookie Posts: 27,756
    davis wrote:

    I would say that doing about 900 miles would result in cassette wear.
    'Would' you say that because you know, or because you are guessing?

    My last cassette (bought used with unknown mileage) lasted 3200 miles (and 3 chains).
  • markhewitt1978markhewitt1978 Posts: 7,614
    Cassettes can last 300 miles or 10,000 miles, it entirely depends on the conditions, shifting under load, the condition of the chain etc. I knacked a cassette in 200 miles running it on a manky old chain. Current cassette has 1,500 miles and no sign of issues yet.
  • The RookieThe Rookie Posts: 27,756
    Agreed, but your also agreeing that saying 900 miles would (rather than could or may) result in cassette wear is wrong!
  • markhewitt1978markhewitt1978 Posts: 7,614
    The Rookie wrote:
    Agreed, but your also agreeing that saying 900 miles would (rather than could or may) result in cassette wear is wrong!

    Yup, it 'could' be. As said it's more likely cable stretch that's the issue.

    And for the OP, don't change to 5700, awful groupset. Get 4700 if you must.
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