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shimming a bearing?

bobs bikesbobs bikes Posts: 589
edited April 2012 in MTB workshop & tech
funny one this.... a customer has a ltd edition 24/7 jump bike which has a knacked BB axle. the old one is 20mm and the new one is 19mm splined. the old bearings fit the bike but not the axle and vice versa, i cannot get another 20mm axle as they dont make them anymore and there is no bearing on the market that will fit. as they are a press fit external item, do you reckon a shim on the outer edge of the bearings would be suitable and safe?

Posts

  • The RookieThe Rookie Posts: 27,802
    No......it won't stop the axle moving in the bearing under load (weight of rider), then it will be spinning eccentricly.
    What OD and width of bearing? Must be an off the shelf that will fit!
    Current steed - Whyte T129, 2013 frame, mongrel Revelations, Giant dropper, Stans S1 wheelset. 12, Magura Trail Sport brakes, 1x11. 12.8Kg
  • mikeagemikeage Posts: 150
    What cranks and BB are they? Is it an old style (USA) BMX BB? Photo's maybe necessary!

    You can get shims for 19mm axles (used in Profile cranks) to fit 20mm bearings

    http://activesport.co.uk/shop/article_C ... ml?pse=coa

    But, importantly, the axle should match the crank!
  • bobs bikesbobs bikes Posts: 589
    cheers guys, ill get some pics up when i can find my usb lead.....
    that shim kit looks just the job mikeage, ill speak to the customer!

    speaking to a bearing manufacturer, there is no bearing on the market that will fit the inner (19mm) and the outer (42mm) diamiters, one of these measurements converts to inches only and is not metric.
    stupid bloody bikes! ...even the supplier of the bike sent a new 19mm axle and they cant get a 20mm one anymore!
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