I’m looking at a new gravel frame (ally) that comes with one of the above. Now I’m generally pretty anti-PF BBs as they seem to cause no end of grief and BSA just works, but the rest of the frame is right, so I’m tempted to try it.

Cranks wise, the boring sensible option would be GRX810, so 24mm axle and I’d probably just stick with a Shimano BB to match. Plastic cup on metal frame, so hopefully creak free? Do the bearings last OK?

…but with my wonky pedalling and love of filth the black GRX cranks will look rubbish in a couple of rides, so there’s a bit of me that’s being tempted by Hope RX cranks in silver which are somewhat lighter, somewhat more expensive(!) and 30mm axle. Looking at the 30mm PF41 BB setups -there seems to be no external shielding (other than the bearing seal) and no tube inside between the bearings, so I’m worried this option will be really vulnerable to water/grit ingress. Any thoughts?

Thanks!

I’ve not had any bother with PF41 with Shimano cranks & bbs.

I’d never put a 30mm axle in a 41mm shell.

Invisiframe do crank protectors don’t they?

Anecdotally I’ve found al frames to be fine with press fit. I’ve taken to using a tiny, tiny smear of thread lock on shimano cups but I think that might just be habit/paranoia.

Given the choice I’d have threaded but if I really wanted a bike I wouldn’t let pf41 put me off (case in point, my bowman foots cray).

As above, not a chance I’d be using a 30mm axle though.

Had a plastic Shimano RS500 PF41 BB on my XL 2020 Norco Search XR A1 gravel bike (alu frame), running Shimano GRX600 cranks. The BB lasted 159 miles before loud creaking ensued. Took the cranks off and the drive side bearing/cup basically fell out of the frame – there was evidence it had walked in the BB shell and the cup had also cracked. I’m 6’4″ and 90 kg.

I replaced the BB with a Hope PF41 that is all metal, the cups are held in the BB shell by a thread-in tube and the bearings are able to be changed without removing the cups from the frame. The bike is now up to 837 miles, no creaks since changing the BB to the Hope one. I did have to fit a 0.5 mm spacer on the crank axle to get the chainline right for the front mech.

It baffles me why Shimano would make a PF BB out of plastic, not fit for purpose. I have no issues with the concept of PF BBs, it allows for a bigger BB shell so more scope for a stiffer BB/chainstay and seat stay junction. Threaded BBs are in essence press fit as the bearings are pressed into the thread-in cups. I’ve 2 other bikes with Hope PF 41 BBs – no issues since fitting.

I agree with the above on not using a 30 mm axle crank in a 41 mm diameter BB shell, the bearings are just not big enough to last well in my experience due to the small gap between the shell and the crank axle and the aforementioned lack of external shielding.

As for scuffing black Shimano cranks, I got protectors for mine from: https://cyclistick.co.uk/collections/shimano

I’ve got a couple of bikes with PF41/BB86/BB92 and never had any problem. IMO the best BB is the Wheels Mfg screw-together – better sealed than Hope

OK thanks y’all…

Those using crank protectors – how well are they lasting? When I’ve tried helitaping seat and chainstays before on MTBs, its usually about 10 wet rides before I’ve worn through both tape and paint…

I had a PF41 carbon frame for a few years.
I had the Hope metal BB, basically a bearing with a lip, and 30mm axle crank.
When the crank broke, it was changed for Shimano plastic BB and 24mm crank.
The cheapo Shimano was utterly trouble free.
Even if cost was the same, I’d recommend the Shimano setup. The fact it’s much cheaper makes it a no brainer.
I mostly like Hope stuff, but their cranks fall into the pointless bling category imo.

If you are wearing through Heli tape, it’s most likely not proper Heli tape.
I’ve had tape in place on frames protecting ss and cs for years without wearing through.

Hope BB and RX cranks here. Fitted to an ally frame used for all sorts.

Roughly 1000miles on them both so far. I did get a creak at one point but that was a dry/gritty chainring and crank interface. A quick clean and lube and all is good.

It’s a very stiff and smooth running setup. I’m pleased with it.

Also to note, I’ve been using a hope bsa bottom bracket with dub adaptors on my mtb. I expected that to last minutes, but I think that is up to 2000 miles now (although has had new bearings a short while ago as one was dry). All those additional contact faces with the thin adaptors haven’t been a problem.

+1 go 24mm

More BB options (Shimano, Hope, Wheels, Token, yadda yadda)

I run a 30mm PF41 but that’s only because I’m using a 30mm RF carbon SixC crank, and it goes through BBs really quickly (Rotor, Hope, it doesn’t matter which)