Shimano UN26 Bottom Bracket

altern_8
altern_8 Posts: 1,562
edited January 2011 in MTB workshop & tech
needed a new bb,and as the original had lasted me 2 years,i decided to order same one.......did a google search for the size i needed and found this>>>>>
http://www.slanecycles.com/scott-aspect ... elivery=39

says it is a 73/113...so ordered one from evans...got it on saturday fitted it to my bike,and went out on a ride sunday............only prob is,i couldnt change to big ring on front mech,it wouldnt shift over to it.

today i took new bb back out,measured it and same as old one........the only difference i can see,is there is what looks like a spacer on drive side(which i cant take out),the old bb spacer is flattened.......

so i was wondering if i need to re-adjust the front mech,or if i have got the wrong bb???

sorry for all the info,but thought id try to answer questions before they where asked. :)
Biking pics

Comments

  • nicklouse
    nicklouse Posts: 50,675
    you need a BB-UN-26 E not a BB-UN-26 as the Mech is a BB mount.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • altern_8
    altern_8 Posts: 1,562
    i missed off the "E",my fault...ive just tried finding what i ordered off evans to show link...but it aint on there site now......only shows the un26,but pic is the un25?

    without being stupid,what do you mean "BB mount"
    Biking pics
  • nicklouse
    nicklouse Posts: 50,675
    shimano_m770_e_front_mech.jpg
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • altern_8
    altern_8 Posts: 1,562
    yep thats the one i have,i re-read youre post and realised what you meant :oops:

    well as i cant send the "bb" back as ive used it....can i fit a normal shimano front mech?
    Biking pics
  • nicklouse
    nicklouse Posts: 50,675
    unlikely.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • altern_8
    altern_8 Posts: 1,562
    ok cheers for the help,ill have a look on the box i got the bb in,and also take out the bb,to make sure it aint a BB-UN-26 E.

    one last question........before i order a new one...if i have to order something else as i cant find the un26 e,will the Shimano UN54 73x113 be ok?
    Biking pics
  • wordnumb
    wordnumb Posts: 847
    altern_8 wrote:
    ok cheers for the help,ill have a look on the box i got the bb in,and also take out the bb,to make sure it aint a BB-UN-26 E.

    one last question........before i order a new one...if i have to order something else as i cant find the un26 e,will the Shimano UN54 73x113 be ok?

    Nah, if you have a BB mounted front mech you'll need a BB with a model no ending E. UN(two numbers which basically refer to the quality of the BB, higher meaning better) E (meaning it's a BB to be used with a BB mounted mech) 73x113 (dimensions of the unit - these need to be the same).

    A UN54 73x113 will cause the same problem. A UN54E 73x113 will work.

Categories