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BB30 to hollowtech

shiznit76shiznit76 Posts: 640
edited September 2017 in Workshop
hi, I am thinking of buying a Fuji transonic 2.5 2nd hand. In the blurb it says it comes with Oval Concepts 520 chainset with a press fir BB30 and Praxis conversion bottom bracket. Question is, how easy would it be to change this to a shimano 105 hollowtech chainset? I am unsure if the original chainset is hollowtech, hence the conversion kit, or would I need a different BB altogether? All advice, as always, much appreciated

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  • You can buy adapter cups that do a reasonably decent job and will allow the use of 24mm (hollowtech) chainsets. The alternative is getting a sleeve you press into the frame but this will invalidate your warranty so best not used on a brand new bike. If the one your getting is out of its warranty period it may be worthwhile. I fit an FSA one to one of my bikes. Worked a treat. Completely quiet and was able to fit an Ultegra chainset on a BB30 frame
  • mugensimugensi Posts: 558
    If he's planning on buying the bike second hand then I'd imagine any warranty is obsolete anyway.

    I fitted an FSA sleeve to my BB30 frame about 2 years ago in order to fit a 6800 crankset, its been 100% since, silent and creak free, thankfully.
  • mugensi wrote:
    If he's planning on buying the bike second hand then I'd imagine any warranty is obsolete anyway.

    I did say that. I was putting the warranty issue there cos other people read this too who's bike may be in warranty. And second hand bikes can still be in warranty if bought from a recognised dealer. Ex display models or demo bikes the shop can still offer a manufacturers warranty for a limited period after sale.,
  • shiznit76shiznit76 Posts: 640
    what would I search for for these sleeves? Are they simple enough to fit?
  • shiznit76 wrote:
    what would I search for for these sleeves? Are they simple enough to fit?

    You will need a bearing press. You can either buy a proper one from wiggle etc or you can make one from a threaded bar, washers and bolts. So long as the washers are larger than the BB shell you can press in a sleeve pretty easily. It's worth taking your time as it requires patience to do.
  • shiznit76shiznit76 Posts: 640
    or a trip to LBS sounds more likely
  • svettysvetty Posts: 1,904
    You could remove the Praxis GXP BB and instead install a Hollowtech II version but I'm not sure you'd gain much if the existing OEM crankset /BB is running smoothly. It's easy enough to replace the rings if they are worn without messing with the BB - a 105 chainset isn't that much better than the OEM one currently fitted TBH.
    If the existing BB is past it then once you remove it you could install whatever you wanted into the clean BB shell - or just replace the BB with a new GXP one and re-fit the Oval Concepts cranks?
    FFS! Harden up and grow a pair :D
  • shiznit76shiznit76 Posts: 640
    is it to go from 52/36 to a compact 50/34 that I want to make change for
  • Try one from here - https://www.c-bear.com/ - from the pdf they do a ceramic bb30 to hollowtech that won't use crappy shims or spacers

    I have had mine for 6500miles - no issues and no creaks

    Bargain for E100 :D:D
  • ayjayceeayjaycee Posts: 1,277
    When I first read this, I wasn't sure whether or not the frame was 'native' BB30 or not and therefore didn't comment but, if that is the case, here's another shout for a C-Bear. When my FSA SLK Light / BB30A equipped Synapse Carbon started creaking at the BB, I bought the relevant C-Bear kit and fitted an Ultegra 6800 Chainset. It's still creak free but I have only done about 1500 miles since the change. I suppose that the cheaper option would have been to just refurbish or replace the old BB30 bearings but, if I'm honest, I was looking for an excuse to fit the Shimano chainset as the fact that the bike was not 'full Ultegra' always sort of niggled at me. I know that shouldn't matter but when did common sense ever come into these things? Also C-Bear were a pleasure to deal with - great communication and quick delivery, albeit a quite a high price (relative to BB30).
    Cannondale Synapse Carbon Ultegra
    Kinesis Racelight 4S
    Specialized Allez Elite (Frame/Forks for sale)
    Specialized Crosstrail Comp Disk (For sale)
  • Nick PayneNick Payne Posts: 288
    shiznit76 wrote:
    is it to go from 52/36 to a compact 50/34 that I want to make change for
    Then just replace the chainrings. The Oval Concepts 520 is a 110BCD chainset and will take 50/34 chainrings.
  • ayjayceeayjaycee Posts: 1,277
    Nick Payne wrote:
    shiznit76 wrote:
    is it to go from 52/36 to a compact 50/34 that I want to make change for
    Then just replace the chainrings. The Oval Concepts 520 is a 110BCD chainset and will take 50/34 chainrings.
    See, that's the sort of common sense that I was talking about!
    Cannondale Synapse Carbon Ultegra
    Kinesis Racelight 4S
    Specialized Allez Elite (Frame/Forks for sale)
    Specialized Crosstrail Comp Disk (For sale)
  • shiznit76shiznit76 Posts: 640
    Nick Payne wrote:
    shiznit76 wrote:
    is it to go from 52/36 to a compact 50/34 that I want to make change for
    Then just replace the chainrings. The Oval Concepts 520 is a 110BCD chainset and will take 50/34 chainrings.

    would it take any 110BCD chainrings?
  • Nick PayneNick Payne Posts: 288
    AFAIK the Oval Concepts is a standard 5-arm 110 BCD crankset and takes standard 110 BCD chainrings. The present chainrings should have the BCD marked on them somewhere. I use quite a lot of TA Zephyr chainrings, which are reasonably priced and seem to last pretty well. A pair of them from somewhere like bike24 are going to set you back somewhere around €70.
  • svettysvetty Posts: 1,904
    I think the OEM chain-rings are Praxis so you could just get Praxis ones - these are decent quality with reasonably good shifting
    FFS! Harden up and grow a pair :D
  • I've never had a creeky BB30 bracket and I've been running them since the very beginning; raced, toured, commuted, used and abused. But then I don't rely on a LBS to fit or maintain.
  • Been looking at some 110bcd chainrings, but most seem to be for 10 speed, take it this means they wouldn't work on my 11 speed set up and chain?
  • napoleondnapoleond Posts: 18,633
    Then you're looking in the wrong place!
    Twitter - @NapD
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    ABCC Cycling Coach
  • yeah I do see some 11 speed, but mostly say 10 speed, my question is, are the 10 speed ones not compatible with 11 speed set up
  • shiznit76 wrote:
    Been looking at some 110bcd chainrings, but most seem to be for 10 speed, take it this means they wouldn't work on my 11 speed set up and chain?

    A lot of FSA chainrings have 10/11 on them so they are compatible with both
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