Any question answered...

The holes do have a recess but I'm mounting it on a starfish crank so the bolts are screwed in from behind. I could flip the chainring to make use of the recesses but the teeth are slightly offset on the side with the recesses. I'd like to have it as in the fourth picture.

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Any top tips for removing an aluminium press fit bottom bracket from a carbon frame when the halfwit who installed it (not me this time) has used epoxy to keep it in place? I've tried heat (hot air gun) and Brute Force And Ignorance (pounding away at it with a lump hammer and a long length of brass bar) and it's not budging. My current plan is to cut it into sections (carefully) and then try and peel it out in bits, but any suggestions for better plans will be welcome.

Leaving it in place isn't an option. It's a Rotor 4624 bottom bracket for 24mm axles, I'm fitting a 30mm axle crankset, and I'm all out of negative shims.

Will a high street locksmith cut a new d-lock key? I've lost one so using my spare

Leaving it in place isn't an option.

Especially now that its received the lump hammer and brass bar treatment.

Sorry that's not helpful but you might be stuffed - epoxying stuff in to carbon is a really bad idea unless you want it in there for ever.

Press fit direct into the carbon, or into an alloy sleeve which is bonded into the frame?

The brass bar is a nice close fit in the BB cup, and I've been lamping it from the reverse side, so the recess for the bearing is untouched. Still won't fit a 30mm axle though. I have a horrible feeling I'm going to end up having to cut and file the damned thing out.

Directly into a carbon BB shell - it's a 2012 Cervelo R3 Team frame.

I have a horrible feeling I'm going to end up having to cut and file the damned thing out.

I guess caustic soda isn't going to be too nice to the crabonz...

I can't imagine you are going to end up with a great surface on which the new BB is going to press in to if you cut it out?

If it's not dead, I'd be looking for a 24mm crank and cursing the guy who thought gluing it in was a good idea

I'd be tempted to hand the frame to a carbon repair place, as violence sufficient to remove the BB will need to be repaired before the frame can have a fresh BB pressed in.

I'm working on the assumption that once I get it out I'll need to Loctite the new bearing cups into place, and possibly use a thread-together BB. I thought about just getting a 24mm crank, while the 24mm BB is still reusable, but I've got two Rotor 3D+ cranksets with P2M power meters on them, and I can't really justify getting another P2M crankset. I have, ahem, enough already.

Caustic soda isn't an option I'd really want to adopt - fine for a steel frame, but pouring caustic into a carbon frame seems a bit risky.

What on earth does 'investment cast' mean?

https://en.wikipedia.org/wiki/Investment_casting

lmgtfy
https://en.wikipedia.org/wiki/Investment_casting

What on earth does 'investment cast' mean?

The act of using a rod and line to project an attached small fish into a body of water in the hope of pulling a bigger fish out of it.

Any chemical that could potentially reduce the adhering epoxy will first attack any other epoxy it can find, i.e., the topcoat of the carbon fibre frame,
but you have already worked that out.
As physical force has failed,
the last option is the cutting one.
Depending upon the bond strength you may need 4 or 5 cuts.

sorry

Yes, I'd already decided that just dunking everything in MEKK in the hope of softening the epoxy would be a bad idea. My plan at the moment is the section the BB cup into quarters and try and peel it off, relying on the hopefully limited peel strength of the epoxy. If it buggers up the BB shell then I can always get it repaired once the cup's finally out of the way. Or just bodge it again.

I'm not that familiar with press-fit BB (and it sounds like I don't really want to start), but could you close-off one side of the BB and partially fill the BB with a solution which will work away at the epoxy from the inside?

partially fill the BB with a solution which will work away at the epoxy from the inside?

It's a carbon frame - any epoxy eating will eat the frame itself, too.

if I buy this, can I assume that wolf have made the holes from the bolts thick enough to just use standard chairing bolts for DA cranks as they don't seem to sell chainring bolts specifically for them?

https://www.sigmasport.co.uk/item/Wolf-Tooth-Components/110-BCD-Asymmetric-4-Bolt-Chainring-for-Shimano-Cranks/FUU1

Ah, missed the part about the carbon BB shell!

If you're talking about uploading. It took me many attempts to get it working!

Turns out my blocker decided to bar upload sites all on its own.

In case it's a kryptonite evo or better, they send you a replacement for free, all the way from the US of A.

https://www.kryptonitelock.com/en/customer-service/order-keys.html

Aero chainring does not clear the crank arm properly.

Think I know the answer to this one already, but do I take a file to the chainring or crank in this scenario?

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