Crank wont go into PF30 bottom bracket

buffoon
buffoon Posts: 49
edited June 2016 in MTB workshop & tech
I have got a new Stumpjumper FSR Evo 29er 2015 frame, and I am putting all the bits from my 2014 Camber evo onto this new frame.

I am struggling to get the crank into the BB. It is a Wheels PF30 BB, and the crank from the camber evo should be compatible ("Chainset: Custom SRAM S-1250, 10-speed Trail double, PF30 spindle"). However, I can get the crank ~95% of the way in, but it refuses to budge the last ~6mm, so although it looks rideable, it is very clearly not symettric. I am not sure whether I need to bash the crap out of it with a hammer, but this is a new frame and i am reluctant to do that. Even to get the crank to where it is, I had to use a fair amount of force (with a thick cloth in between to soften blow).

Is is normal for cranks to be ridiculously tight? Is brutal hammering a normal requirement? Any advice appreciated, before I give up and go pay a man to rescue my mess.

(If I ever find the guy who invented Pressfit I will waterboard them...)

Comments

  • The Rookie
    The Rookie Posts: 27,812
    Not an expert on press fit but the following comes to mind
    1/ nothing to do with the frame as its the inner race(s) that will be causing the issue
    2/ what happens if you try to insert it from the wrong side, that is does it say which of the two bearings is causing the issue

    I do know that HT2 requires a fairly heft slap with the palm of my hand to go in the last 10mm ish as the part of the axle which is meant to be snug in the bearings goes in, a little grease to help it slip in works wonders.
    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.
  • buffoon
    buffoon Posts: 49
    ok in the end I gave in and went to a man. I was rather embarrassed when he just gave the crank a big back with a plastic hammer, and it fitted fine! Oh well - all's well that ends well.

    Learned my lesson - modern BB's are indeed ridiculously tight and just need a bit of brutality.