Forum home› Mountain biking forum› MTB workshop & tech

Rear Cassette 10 Speed from 11-36 to 11-40

faceplant77faceplant77 Posts: 21
in MTB workshop & tech
I do alot of hill climbing to get to work on my Calibre Bossnut V2, and saw a Cassette with 11-40T, would this make it a little easier climbing up the hills.
I have 20 gears 2 x 10, 22 x 36 on the front and 11.-36 on the rear.
By adding the 11-36 Cassett would I need to add extra chain links as I'm replacing the chain shortly due to wear.

Posts

  • JBAJBA Posts: 2,687
    Yes, if you change to a 11-40T cassette you will probably have to extend your chain.
    Search YouTube for tutorial videos. There are plenty on there. The largest sprocket - largest chainring and add 2 links method usually works for me.
    “Life has been unfaithful
    And it all promised so so much”

    Giant Trance 2 27.5 2016 ¦ Sonder Broken Road 2021¦ Bird Zero Mk1 ¦ Giant Revolt Advanced 2 2019 ¦ Giant Anthem 3 2015 ¦ Specialized Myka Comp FSR 2009
  • reaperactualreaperactual Posts: 758
    edited September 2020
    Check your rear derailleur's max low sprocket capacity to be sure it has the range to accommodate a 40t low gear.
  • mully79mully79 Posts: 138
    Running a double on the front and wide range cassette is probably asking for trouble. Thats a big difference in chain length.
  • oxomanoxoman Posts: 8,702
    You should be ok with the 11/40. I currently run a 11/42 on my double chainset giant anthem with no issues. I just added a couple of extra links. Just don't go big to big or small to small as you'll be at the extremes of your rear mech.
    Too many bikes according to Mrs O.
  • JBAJBA Posts: 2,687
    You’ll have no trouble running an 11-40T cassette with your chain set.
    My wife’s Giant Toughroad is equipped with an 11-42T cassette and 32/44 chain set as standard and it works just fine.
    “Life has been unfaithful
    And it all promised so so much”

    Giant Trance 2 27.5 2016 ¦ Sonder Broken Road 2021¦ Bird Zero Mk1 ¦ Giant Revolt Advanced 2 2019 ¦ Giant Anthem 3 2015 ¦ Specialized Myka Comp FSR 2009
  • mully79mully79 Posts: 138
    36 + 40 = 76
    22 + 11 = 33
    76 - 33 = 43t derraileur capacity required.

    shimano deore shadow long cage has a capacity of 43t so it will be ok. The maths says its not as extreme as i thought !

    Still a bit too flappy chain for my liking !
  • reaperactualreaperactual Posts: 758
    edited September 2020
    .
  • faceplant77faceplant77 Posts: 21
    Thanks guys but just want to know how many links to add, is 2 or 3 enough?
  • JBAJBA Posts: 2,687
    You need to size the chain. Wrap the new chain around the largest sprocket and largest chainring, missing out the rear derailleur, and add two links.
    As I said in my previous post, search YouTube for tutorial videos.
    “Life has been unfaithful
    And it all promised so so much”

    Giant Trance 2 27.5 2016 ¦ Sonder Broken Road 2021¦ Bird Zero Mk1 ¦ Giant Revolt Advanced 2 2019 ¦ Giant Anthem 3 2015 ¦ Specialized Myka Comp FSR 2009
  • steve_sordysteve_sordy Posts: 2,080
    Thread the chain as normal.
    Choose the biggest gear on the front and the biggest on the back.
    Adjust the chain length so that the mech arm is pointing forward at 45 degrees

    One last check, fully compress the rear suspension. If you cannot because the chain is too tight then lengthen the chain and check again. This step is important on a full suspension bike.

    The reason for the last check is that some bike geometry designs extend the rear centre and if the chain is not long enough to cope with this extra, you may suffer severe damage to the rear mech.
Sign In or Register to comment.