BB30 to Shimano

ben_yyc
ben_yyc Posts: 2
edited January 2016 in Road buying advice
Hi

I have 2 bikes with Ultegra cranks (both are BB86).

I'm currently looking at power meter, and it look like I will end up getting a quarq bb30.

I will like to be able to switch the power meter from bike to bike.... so I need to replace the BB on both bikes. But I will also like to keep using Ultegra crank on the other bike (ie: home trainer)

So it possible to get a BB30 to shimano adaptor... or do I need throw away my ultegra cranks and get a normal bb30 crank?
(or did I get the BB convention backward)

Comments

  • MikeBrew
    MikeBrew Posts: 814
    By BB86 presumably you mean they are press fit(PF) frames rather than running external threaded cups ?

    That being so your best bet would be to get a Quarq on GXP., though that would mean swapping out your Shimano bearings for PF SRAM ones : GXP runs a stepped axle which redudes from 24mm to 22mm on the non drive side.
    Rotor do bearings that will run a 30mm axle in a BB86 frame*, but it's not ideal as you end up with smaller bearings as the difference between the inside and outside diameters of the bearings is small. This means smaller bearings which potentially wear quicker.( 41mm-30mm leaves not a lot of room for races and bearings)

    Which ever solution of these 2 solutions you choose, your Shimano cranksets won't work with (to my knowledge).

    A stages PM might suit your needs better fit-wise, though I have heard that they can be unreliable and have battery life issues.

    http://rotorbike.com/products/road/bb86_40 *

    http://problemsolversbike.com/files/tech/Bottom_Bracket_Standards_Reference.pdf
  • Grill
    Grill Posts: 5,610
    Just get a Rotor 3d Power2Max and you won't have to change anything. If you insist on Quarq then get a GXP and change both BB's. BB30 is a steaming pile of crap.
    English Cycles V3 | Cervelo P5 | Cervelo T4 | Trek Domane Koppenberg
  • MikeBrew
    MikeBrew Posts: 814
    Of course, if you have in mind a particular example of a Quarq on a BB30 that is a bargain, you could buy it then convert IT to GXP. The PM spider is only held to the cranks by 3 torx headed bolts and some loctite.
    A cheap GXP SRAM 900/950 series (or even SRAM force 22), from Ebay etc could then provide the donor cranks and axle.

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