Its time for new cranks. Already have the chainrings so I’m a little reluctant to pay for another set. The Middleburn RS7 and 8 keep catching my eye, especially the RS7 with the lifetime guarantee. Is anyone still using square taper cranks and bottom brackets? Is getting new bottom brackets a problem?

Yes, and I wouldn’t change.
Did once and went back.

Even managed to find a brand new XTR UN91 on fleabay for £13!

Yes. The ‘new’ UN54 is OK. The plastic NDS cup is more brittle than of old, and the cartridge is a different diameter, so you can’t use an old decent plastic/alloy NDS cup from a UN53/73/93, or for that matter, from an octalink BB. But they’re OK.

Old RF or proper bling Royce etc sq taper BBs are still ace.

rs7s are awesome – as far as bb’s go, you can fork out for a phil wood square taper with awesome changeable bearings, or have numerous un54s for £11 each

rjc x-treme for the best price

yes – RS7 on UN72 (found a NOS). Have one more UN72 which I’ve pencilled in for 2020 to 2040.

Currently using UN54 BB with no problems. About £13 to 16 at the moment.
Obviously if you want to spend more you could go for royce or phil wood etc.

I run one on my winter off road commuter. UN54 weighs a bit but is dead cheap and lasts 2 to 3 years used daily in wet and muddy conditions.

Yup- and as mentioned above, get a high end BB and replace the bearings as and when (if!) needed.

Oh yes, one RS8 on a UN73, and another on a Phil Wood Mag/Ti BB.

Trouble is that I get a alu/titanium creak that I can’t quite kill off 🙁

My son pinched my XT one for his bike (the third bike it’s been on in the ten years I’ve owns it). Still running as well as the day I bought it for about £20.

All my bikes are octalink at the mo, but when those BBs fail I’ll be going to square taper: fitted properly, can’t be beaten IMHO.

yeah rs8 on un54 here, lovely

have always had square taper

RS7 on cheapie ST BB here – no problems.

UN54 seems fine, still going strong in our commuters. Wouldn’t personally put Middleburn on a bike but there’s nothing wrong with squaretaper in principle.

Another RS8 with UN5? here. I also use a square taper TA Axix steel BB on the fixed road bike – Very nice unit, not silly money and most importantly – standard cartridge bearings mean it’s a doddle to replace worn out bearings, with whatever grade of bearing takes your fancy/fits your budget. Worth a look IMO http://www.specialites-ta.com/produits/boitiers_gb.htm

there’s a lot right with square taper as well – a decent interference-fit, unlink some of the later interfaces.

Yeah, I’ve got a nice Dura-Ace crankset and a couple of Sugino cranksets running on probably UN5n BB’s. They’ve been in there so long I can’t confidently say what they are!

(… and I very lightly grease the tapers on mine too 😈 )

there’s a lot right with square taper as well

I think the only thing wrong is people not fitting them correctly (i.e. too loose), and that it isn’t the ideal system if you want to keep uninstalling and reinstalling the same cranks. I’ve seen arguments about strength and rigidity, but as I’ve never had an issue there (and I weight 16 stone) so it’s all a bit academic really.

(… and I very lightly grease the tapers on mine too )

Yup, me too.

17 stone on a single speed and no problems in two years, used two or three times a week, and thats just a £16 shimano bb , 🙂

Yep UN54, Race Face Turbines on SS, UN54, old Bonty cranks on commuter. Thought about getting a Phil Wood to replace the one on the SS that just wore out but for the cost of the fitting tool (nevermind the BB) I could get a new UN54!