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I've been doing some googling on fixing the annoying creaking in my bottom bracket. It's all good if it's in easy gears. The moment it's in the big front chain ring and small rear gear (ie. I'm putting lots of pressure on the pedals, it starts creaking a lot). I've done some googling but I'd like to confirm a few things. I've got a Ribble carbon fibre frame in my bike. Looking at the invoice from my bike, it came with the following bottom bracket: BB71 Road Press Fit BB Cups 86.5x41

  1. My understanding is that BB71 is specific to Shimano Ultegra (which I have) but the general type of this BB is BB86. Is that correct?
  2. If so, the right tools for the removal would be Park tool BBT-90.3
  3. The following tool will be suitable for installation: https://www.parktool.com/product/home-mechanic-bearing-cup-press-hhp-3 Is that correct?
  4. I'm going to apply some retaining compound. I've ordered Lactite 680 - Do I need anyting else, any primer or anything?
  5. I'm also going to buy a new BB71 to replace the old one. Looking at the photo, it looks like it https://www.chainreactioncycles.com/shimano-bb71-road-press-fit-bottom-bracket/rp-prod61803 Looking at the picture of BB71, it looks like it comes in one piece. Is it just a picture and it'll be in parts (eg. 2 cups and the tube/cartridge)? Otherwise, if it's all in one piece, how am I supposed to use the removal tool to extract it from frame?

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Thank you. I don't want to buy the wrong things.

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    Press fit bottom brackets are notorious for creaking. Just changing the bottom bracket might not be enough, it might still creak. You might need to change your frame too to something that has a threaded bottom bracket, which might be a tricky interface on carbon fiber, but hey, it's a good opportunity for upgrading to a metal frame.
    – juhist
    Jul 17, 2021 at 11:24
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    What @juhist says about press-fit bottom brackets is true - but you don't need to change your frame to use a threaded bottom bracket. Product recommendations are off-topic here, but there are products like this around: wheelsmfg.com/bottom-brackets/bb86-92/… There's a reason why those things sell - press-fit bottom brackets are a plague foisted on cyclists by manufacturers.
    – Andrew Henle
    Jul 17, 2021 at 14:14
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    @juhist: This is really not helping, a non-constructive solution to a problem that may be solved in a better way. You don't discard a frame for another one just to solve a problem with a creaking BB.
    – Carel
    Jul 17, 2021 at 18:46
  • @AndrewHenle Some terminology confusion. You are recommending a thread-together BB. Those can help with creaking in some cases, but may not be a panacea if the cups are misaligned or out of dimensional spec. I think many people understand "threaded bottom bracket" to mean a threaded interface like BSA or T47; indeed, those are impossible to retrofit to a frame with a press fit interface (actually, metal frames with PF30 BBs can be threaded to T47 if someone has the skill and the equipment, but that's an edge case)
    – Weiwen Ng
    Jul 18, 2021 at 14:19
  • @AndrewHenle Thanks. Regarding product recommendations - I am not asking about any recommendation. I've asked if the tools I've chosen will be suitable in terms of size/type to do the job.
    – Wasteland
    Jul 18, 2021 at 14:34

2 Answers 2

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  1. No. The B model puts every road Hollowtech 2 crank ever made in a BB86 frame, so yes it is the one you want for your Ultegra, but it's not specific to Ultegra. Shimano's decision to include "BB" in their model names here can cause confusion. Look at the little icons of a mountain bike for the A model and a road bike for the B model. Really simply, the A model is for mountain bikes (BB92, 91.5mm actual shell width) and the B is for road bikes (BB86, 86.5mm actual shell width.)

  2. Yes.

  3. Yes.

  4. 680 is listed by the manufacturer as primerless. The decision whether to go right to retaining compound and which one to choose is yours. In some cases you can take measurements to show what kind of gap fill needs you may be up against, i.e. use a caliper to measure the ID all around the shell to get a sense of what's going on and what the maximum gap is. Threadlockers and retaining compounds have a gap fill spec in their technical data sheets.

  5. Yes, they are two pieces and the photo shows them stuck together.

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  • Great. Thank you for clarifying my questions.
    – Wasteland
    Jul 20, 2021 at 12:55
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The bottom bracket is 3pcs.

These usually don't give much problem and generally are greased in.

Check the chainset spins smoothly with the chain removed. If the bearings feel smooth with the crankset out, you may be able to rectify the problem by refitting the bb unit with grease or loctite.

Pressfit bearings are technically superior to threaded but require higher manufacturing tolerences that are frequently not met, even in some of the more expensive frames.

See Hambini threaded vs press fit on youtube for more info.

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  • Pressfit bearings are technically superior to threaded ...?!?! Huh? How is something prone to not working well and requiring special tools to install and remove "technically superior" to threaded bottom brackets that at worst require a specific but cheap wrench to screw on or off? "Cheaper to manufacture because it has lower tolerances than making sure the threads on both sides are aligned and cleanly cut" is a curious form of "technically superior".
    – Andrew Henle
    Jul 18, 2021 at 12:41
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    @JoeK Yes, I have seen some of Hambini's videos - just wanted to clarify some bits before I make any purchases. So am I correct in understanding that loctite does not need any additional substance (primer/activator). I vaguely remember seeing some videos where it was recommended. Thanks
    – Wasteland
    Jul 18, 2021 at 14:37
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    See Hambini threaded vs press fit on youtube for more info. I watched it. Ooof. Within a couple of minutes he states that an aluminum Dura Ace bottom bracket is made of nylon and then goes on to say should a chain ever drop and gouge a carbon fiber frame like it did to the aluminum frame he's handling, it would crack the carbon fiber frame. I'm not going to watch again it characterize that exactly - he may of added "immediately" or similar. Going back would be too painful - because I've seen - and had - chains drop on carbon fiber frames and gouge the frame a bit - no cracking...
    – Andrew Henle
    Jul 18, 2021 at 21:17
  • I'm surprised you ride anything but the Rivendell, Andrew.
    – Noise
    Jul 18, 2021 at 21:58
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    @wasteland not all Loctite needs an activator. Try using a weak one to start with as you'll want to be able to replace them in future.
    – Noise
    Jul 19, 2021 at 14:16

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