New crankset doesnt fit? wtf?

richardjiles
richardjiles Posts: 137
edited July 2012 in MTB workshop & tech
So I just got my new front chainwheel crankset piece, I put it on and wtf? it goes way too far on, so that my front deraleur will never get it on first gear... man wtf? when ordering the part I made sure all the chainrings were the same size, but I decided to buy a smaller crankarm size, went from 175 to 170, will that make the difference? I dont think so because others talk about buying new cranks with smaller size

UPDATE:
I don't know the previous Crankset, however the new one is shimano altuls
Right, just took readings from my current bottom bracket, its 68 x 110.5
so my new one should be 68 x something, now as long as its altus compatible does it matter?
Kona Fire Mountain Deluxe 09 - Pics out of day

Comments

  • nicklouse
    nicklouse Posts: 50,675
    err yes great. what do you want us to do?

    from what to what?
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • angry_bird
    angry_bird Posts: 3,786
    Like Nick says how can we help based on that. What model do you have now? What model did you have? What size BB do you have? Got enough BB spacers in?
    Angry Bird's offroad bikes
    Winter
    Racey
    Special Favourite

    If in doubt, blame Wiggle.
  • nicklouse
    nicklouse Posts: 50,675
    Angry Bird wrote:
    Like Nick says how can we help based on that. What model do you have now? What model did you have? What size BB do you have? Got enough BB spacers in?
    Does it even use spacers!
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • crispy1980
    crispy1980 Posts: 310
    probs done what i did and ordered a crank set without realising that it has to be matched to the axle length of the bb. sounds like yours isnt and is therefore sitting the chain rings too far in, causing said problems.
  • richardjiles
    richardjiles Posts: 137
    k so how do i go about getting a new bb? its square tapered
    Kona Fire Mountain Deluxe 09 - Pics out of day
  • richardjiles
    richardjiles Posts: 137
    I don't know the previous Crankset, however the new one is shimano altuls
    Right, just took readings from my current bottom bracket, its 68 x 110.5
    so my new one should be 68 x something, now as long as its altus compatible does it matter?
    Kona Fire Mountain Deluxe 09 - Pics out of day
  • nicklouse
    nicklouse Posts: 50,675
    Part numbers?
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • richardjiles
    richardjiles Posts: 137
    New cranks - FC-M311
    Old cranks - FC-MC19
    current but not fitting bb - (UNKOWN) but its 68 x 110.5
    Kona Fire Mountain Deluxe 09 - Pics out of day
  • nicklouse
    nicklouse Posts: 50,675
    You need a 123mm axel.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • richardjiles
    richardjiles Posts: 137
    nicklouse wrote:
    You need a 123mm axel.
    Thanks!!!
    but how did you manage to figure this out?
    Kona Fire Mountain Deluxe 09 - Pics out of day
  • The Rookie
    The Rookie Posts: 27,812
    By looking at the parts technical documents on the Shimano website.

    While 123mm is what you want, some list 122 or 122.5 and they would be fine (0.5mm or 0.25mm isn't going to make a meaningful difference!)
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.

Categories