spindle length BB for Orange Five

ads678
ads678 Posts: 70
edited January 2011 in MTB workshop & tech
Basically, bought a second hand Orange Five frame fitted a BB I already had then realised it's the wrong size!!!

So I need a 73mm BB but what spindle length is best? It's an Octalink BB BTW. The one i've fitted is a 118mm, running granny and middle ring (36t) with a bash, when shifting from granny to middle the chain catches on the swingarm. can anyone tell me what length spindle they have on theirs if using a ocatlink style BB, or does anyone know If a 121mm would be ok or should I go for a 126mm.

I'm thinking if i've got 118 at the moment a 121 wouldn't really give any extra width?

Help, i've been building far too long now I want to ride!!!!!
GT Avalanche 1.0
Orange Five

Comments

  • nicklouse
    nicklouse Posts: 50,675
    it all depends on the cranks.

    got a part number?
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • ads678
    ads678 Posts: 70
    I think It's these http://www.woollyhatshop.com/Shop-By-Br ... _1360.html

    FCM521E866S

    But with the big ring removed and a bash guard fitted.

    It seems like I just ned the chainrings to be a bit further out then the chain will miss the swingarm when shifting.

    I had previously fitted a 68mm BB then realised it should be a 73mm?!?!?
    GT Avalanche 1.0
    Orange Five
  • nicklouse
    nicklouse Posts: 50,675
    find out what the cranks actually are and post the actual part numbers.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • ads678
    ads678 Posts: 70
    I'm pretty sure it's those, It wasn't long ago that I bought them. I'll check later when i'm at home.

    showing my total knowledge on the subject here but, why does it make a difference what the cranks are? Is the spindle length not just a spacing thing?
    GT Avalanche 1.0
    Orange Five
  • ads678
    ads678 Posts: 70
    Yep they're M521's.

    CRC say's that they use a 121 BB, so does that mean that is all I can use with them, or could I go for a 126 to give more clearance or should I not do that as it would mess with the chainline(?) too much?

    Any help gratefully recieved as it's doing my head in now, I haven't ridden a bike since the begining of December cos they are both in bit's!!!!
    GT Avalanche 1.0
    Orange Five
  • Mancunianfightingcat
    Mancunianfightingcat Posts: 2,054
    A 36t chainring will cause the chain to catch the swingarm when changing gear, it used to be on Orange's website that only a 32T could be used, but it seems to have gone now. I use a 34T and that used to catch too, until I messed around with thinner BB spacers.
    Ants
    Orange Blood - Orange 5SE - Marin Rocky Ridge
  • Shotsaway
    Shotsaway Posts: 175
    ads678 wrote:
    Yep they're M521's.

    CRC say's that they use a 121 BB, so does that mean that is all I can use with them, or could I go for a 126 to give more clearance or should I not do that as it would mess with the chainline(?) too much?

    Any help gratefully recieved as it's doing my head in now, I haven't ridden a bike since the begining of December cos they are both in bit's!!!!

    If you fit a 126mm spindle when CRC are advising 121mm, you will end up with an incorrect chainline. The chainline should be approximately 50mm. For example fitting the 126mm would make the front chainline approximately 55mm. An incorrect chainline will put more stress on the chain and the worse the chainline, the worse the efficienty of the drive train.

    If you fit the 126mm you will also have to re-align the front mech.

    More info on chainline

    http://www.sheldonbrown.com/chainline.html

    Edited bit: If you are running a 118mm BB at the moment, that might be one of the reasons the chain is hitting the swingarm. In effect the chain is 3mm closer to the frame.

Categories