No announcement yet.

2011 TREK Marlin BBS02 Build: Chainring issues! Please help!

  • Filter
  • Time
  • Show
Clear All
new posts

    2011 TREK Marlin BBS02 Build: Chainring issues! Please help!

    HI Guys, Long time lurker first time poster.

    I have taken the plunge on a BBS02 for my 2011 Trek Marlin. The install went fine, but upon test ride, it has been victim of chain-suck and is not mating the chain to the Bafang chain ring so well. I did buy a gauge and tested it, the chain was very stretched. I have since purchased a new one and it still seems to be binding up on the sprocket. Like the sprocket teeth are too tall or too wide or spaced too far apart. Any suggestions? I have contacted the ebay seller about this and they seem to think it is my rear sprockets that need replacing. Any ideas? I am stumped and cant be the first person with this issue...


    The bike:

    Chain line / alignment looks decent:

    old chain:

    sample chainsuck:

    new chain, better but still issues:

    freewheel for reference:

    any ideas?

    It looks to me like the chainring is wider than the chain. Is your new chain a 7 or 8 speed chain and not 9 or 10 speed?
    I'd measure the chainring width at the base of the teeth with a micrometer or good caliper and see if the teeth are under 3/32” in width. If it is a narrow-wide ring you’ll need to check width of 2 consecutive teeth.