Which BB to replace Shimano BB71 Road Press Fit

russboy
russboy Posts: 436
edited March 2019 in Road buying advice
So on my winter hack i've noticed if I wobble the crank I can see the BB moving up and down. Replaced the BB71 with the same again and it still does it. So what is out there that I can use that isn't a press fit? Thinking if the BB clamps onto the outside of the frame this should get past this problem(?)

Bike is a 2013 Fuji Gran Fondo 2.1 that originally had a press-fit BB86 bearing in there but when I moved to the 105 I put the BB71 in there and all was well.

Spec of the bike is here:

https://archive.fujibikes.com/2013/Fuji/gran-fondo-21-c

Comments

  • timothyw
    timothyw Posts: 2,482
    I have a Fuji of similar vintage that also has a press fit bottom bracket.

    When you 'moved to 105' did you replace the cranks that came with the bike?

    The stock cranks will not work with a shimano bb71 bottom bracket without an additional adaptor collar - they require a GXP bottom bracket such as this one - https://www.chainreactioncycles.com/sra ... -prod75586
  • russboy
    russboy Posts: 436
    Yes, I changed the crank to a Shimano 105, matched the rest of the equipment then. Hence I moved from the original BB86 to the BB71 to allow me to fit this.
  • ds2288
    ds2288 Posts: 36
    Depends how much you want to spend on it. I put in a Wheels MFG BB86 with angular contact steel bearings and am very happy. If you want the best, get a Hambini BB.
  • keef66
    keef66 Posts: 13,123
    BB86 describes the BB shell in your frame.
    Shimano's BB86 compatible road BBs come in BB71 (Ultegra level) and BB92 (Dura-Ace level) flavours.
    If yours has been correctly pressed in but you're still getting movement it suggests there's something amiss with the BB shell in the frame. Or are you saying the bearings are failing prematurely and giving you play?

    You could try installing another Shimano BB with some Loctite retaining compound?

    Or if you've lost faith in press-fit BBs in general, try one of the Wheels Mfg conversions which screw together
  • russboy
    russboy Posts: 436
    keef66 wrote:
    BB86 describes the BB shell in your frame.
    Shimano's BB86 compatible road BBs come in BB71 (Ultegra level) and BB92 (Dura-Ace level) flavours.
    If yours has been correctly pressed in but you're still getting movement it suggests there's something amiss with the BB shell in the frame. Or are you saying the bearings are failing prematurely and giving you play?

    You could try installing another Shimano BB with some Loctite retaining compound?

    Or if you've lost faith in press-fit BBs in general, try one of the Wheels Mfg conversions which screw together

    I noticed the movement so put a new BB71 in there 10 days ago so the bearings can't be failing.

    Have ordered a tool to remove the BB71 and will have a nose around, including probably removing the (aluminium??) insert that I guess is the shell you refer to.

    Ironically I also have a 2016 Fuji 2.3 Transonic and I took the Ultregra crank out of that yesterday and swapped onto the winter bike to see if any difference and still had the movement. On the Transonic I did have fit a KCNC BB30 Bottom Bracket to Shimano adapter as per below, guess I may just need the same again?

    https://www.sjscycles.co.uk/bottom-brac ... oad-68-mm/
  • keef66
    keef66 Posts: 13,123
    That's an adapter for a BB30 bottom bracket shell, which the 2016 Transonic has. Won't fit your Granfondo.
  • russboy
    russboy Posts: 436
    Yeah sorry, I meant the equivalent for the Gran Fondo
  • keef66
    keef66 Posts: 13,123
    Russboy wrote:
    Have ordered a tool to remove the BB71 and will have a nose around, including probably removing the (aluminium??) insert that I guess is the shell you refer to.

    If there is an aluminium insert inside the carbon BB shell it's likely bonded in and not removable.

    The annoying thing about Shimano press-fit BBs is the likelihood of distorting them on removal which is why Shimano advise against reinstallation.
  • keef66
    keef66 Posts: 13,123
    https://www.sigmasports.com/item/Wheels ... lsrc=aw.ds

    which is probably what the earlier poster has
  • russboy
    russboy Posts: 436
    keef66 wrote:
    https://wheelsmfg.com/bottom-brackets/bb86-92/bb86-92-outboard-abec-3-bb-for-24mm-shimano-cranks-black.html
    which is probably what the earlier poster has

    Nice one, thanks.
  • scott_w1987
    scott_w1987 Posts: 316
    I've got a BB92 that came with a groupset that I bought, Aus relocating so you can have it for the price of postage?
  • russboy
    russboy Posts: 436
    scott_w1987 wrote:
    I've got a BB92 that came with a groupset that I bought, Aus relocating so you can have it for the price of postage?

    Legend!!

    So it's not been used then? Let me know what I owe you and I can get it paid across to you.
  • scott_w1987
    scott_w1987 Posts: 316
    Russboy wrote:
    scott_w1987 wrote:
    I've got a BB92 that came with a groupset that I bought, Aus relocating so you can have it for the price of postage?

    Legend!!

    So it's not been used then? Let me know what I owe you and I can get it paid across to you.

    Brand new no box.

    PM me your address and I’ll get it in a jiffy bag and post it Wednesday when I’m at work. It’ll probably be like £3 but I’ll let you know when posted
  • russboy
    russboy Posts: 436
    scott_w1987 wrote:
    Russboy wrote:
    scott_w1987 wrote:
    I've got a BB92 that came with a groupset that I bought, Aus relocating so you can have it for the price of postage?

    Legend!!

    So it's not been used then? Let me know what I owe you and I can get it paid across to you.

    Brand new no box.

    PM me your address and I’ll get it in a jiffy bag and post it Wednesday when I’m at work. It’ll probably be like £3 but I’ll let you know when posted

    Perfect, thanks again.

    PM on it's way.
  • russboy
    russboy Posts: 436
    Starting to think the BB is not the problem.

    this metal shim that sits inside the frame that the BB sits in has movement by hand. If I wiggle it water comes out and that suggests to me there is too much play in there.

    33517103448_a00f6fed9e_z.jpg
  • timothyw
    timothyw Posts: 2,482
    Yeah, sounds like one for the Fuji lifetime frame warranty. Shouldn't be any play at all in the bottom bracket area.

    I did suspect that earlier to be honest, never had a problem with shimano press fit bottom brackets.
  • russboy
    russboy Posts: 436
    TimothyW wrote:
    Yeah, sounds like one for the Fuji lifetime frame warranty. Shouldn't be any play at all in the bottom bracket area.

    I did suspect that earlier to be honest, never had a problem with shimano press fit bottom brackets.

    Lol, didn't know there was such a thing!

    God knows how to get that underway though.
  • timothyw
    timothyw Posts: 2,482
    Take it back to where you bought it, they'll be able to arrange the repair/replacement (Evans cycles presumably?)

    If it's second hand then you are probably best just finding a carbon bike repair place to reglue the shell.
  • russboy
    russboy Posts: 436
    TimothyW wrote:
    Take it back to where you bought it, they'll be able to arrange the repair/replacement (Evans cycles presumably?)

    If it's second hand then you are probably best just finding a carbon bike repair place to reglue the shell.

    Yep, got it from Evans on the ride to work scheme.

    Have emailed Fuji direct, don't want it costing me any money via Evans and there isn't one local to me, so will ask some questions first and go form there.
  • russboy
    russboy Posts: 436
    Wouldn't you know it the frame has a 5yr warranty and I got the bike in June of 2013 so warranty claim is not happening.

    What I did do at the weekend was install another BB but put one layer of electrical tape on the cups before tightening it all up.

    Only done 1.5 commutes so far so 10 mile or so but no problems so far. Last time it came back straight away, time will tell if it's coming back again or not.
  • keef66
    keef66 Posts: 13,123
    If the alu insert is moving in the BB shell electrical tape isn't the answer. In fact it isn't the answer to anything BB related.

    Get a carbon repair outfit to glue the thing back in properly.

    Or are you saying the insert isn't moving but the pressfit BB was loose? In which case some kind of retaining compound would be a more permanent solution than plastic tape.
  • russboy
    russboy Posts: 436
    Of course electrical tape isn't the answer but it's free and working, for now.

    The insert is definitely moving. There is a bolt through the middle to stop it sliding about that also holds the cable guide in place under the frame but the weather has got to that as well as it won't undo and just spins. So that would need to be drilled out first before it could be reglued.

    The only reason I think the electrical tape is working is it must be forcing the shim to expand ever so slightly making it a tighter fit inside the frame.

    Don't really want to spend any money on a 6yr old winter bike, carbon or not, although there is nothing stopping me bonding it back in with the correct chemicals.

    Will prob attack it when the weather is better, when I'm not relying on the bike, as I can then use my Fuji 2.3 Transonic. Just don't wanna use that now with the frame being unmarked, carbon wheels etc with all the rubbish on the roads.
  • russboy
    russboy Posts: 436
    So took the plunge and took out the BB, sadly the tape method was so good and strong the BB didn't make it and is now in around 10 pieces!

    To get the shell out there is a bolt that holds in the cable guide under the frame, that then sits inside a hole in the shell, helping it to stop it from moving. The captive part was no longer captive and was between the inside of the frame and the shell, so I had not choice but to drill it out.

    Then had to tap the shell out, good old 32mm socket did the job. Only around 1cm of contact either side of the shell to the frame, but cleaned it all up with wire wool and slide it 3/4 of the way in using the long bolt, 2 massive washers and wing nuts to make sure it was square. Mixed up some epoxy resin that I know sets very well, smeared all inside one edge of the frame and on the other side on the shell still to be pulled into the frame. Used the bolt etc to pull it in completely making sure it was square and flush.

    Left it for 24hrs

    Put a 10mm bolt inside the shell out through the frame (using existing hole) and 10mm nut on the outside and tightened up to hold the cable guide, nipped it put fairly tight so it will help the shell stay firm as well I think. Ground off the excess thread with my dremel (copy), took the nut off, underseal the whole lot, nut on, more underseal, dried in the sun. BB back in and crank in and all is solid at the moment.

    Won't really know if it was a success until I ride it and load it up, but lost nothing but time (& and a BB!) if it doesn't work.

    32513544977_6dc26e86c8_b.jpg

    32513545587_5495f1ea71_b.jpg
  • keef66
    keef66 Posts: 13,123
    Top DIY fixing there! Sounds like you've done as good a job as you could have. I'm betting it's now the strongest part of the frame...
  • russboy
    russboy Posts: 436
    keef66 wrote:
    Top DIY fixing there! Sounds like you've done as good a job as you could have. I'm betting it's now the strongest part of the frame...

    Lol, i'm a tight ar5e so will take on almost anything on a car/bike/house!

    Haven't used it yet as the sun was out this morning so had to use this, it's so much more fun to ride!!

    47257531292_e32e599768_b.jpg

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