which HollowTech II...
 

[Closed] which HollowTech II BB for a commuter.... ?

 jeb
Posts: 0
Full Member
Topic starter
 

Hello

sooooooooo, what is the smart choice at the moment.. ?


 
Posted : 12/09/2019 9:14 pm
Posts: 5043
Full Member
 

I’ve had an ultegra on my cx bike for a couple of years, works just fine.
I think I paid around £30 for it or so.
Just make sure you don’t over tighten it and it’ll be fine ime.


 
Posted : 12/09/2019 9:17 pm
Posts: 9010
Free Member
 

Deore BB52


 
Posted : 12/09/2019 9:21 pm
Posts: 10975
Free Member
 

XTR for around £30, fit and forget.


 
Posted : 12/09/2019 9:34 pm
Posts: 27
Free Member
 

Ultegra or XTR depending on the frame, fit and forget for years.


 
Posted : 12/09/2019 9:42 pm
Posts: 0
Free Member
 

I'm currently running a praxis works on my soul, am impressed with how well sealed it is. After a few months, I reckon it's as good as my previous hope one at a fraction of the price. Bearings are replaceable and the chainset runs directly on the bearings, none of those daft plastic top hats.
https://www.merlincycles.com/praxis-standard-bottom-bracket-93679.html


 
Posted : 12/09/2019 10:38 pm
Posts: 12648
Free Member
 

I have used Ultegra for years all year round but not for committing. They last a few years and only cost around £18 on eBay so good enough for me.


 
Posted : 13/09/2019 8:05 am
Posts: 43888
Full Member
 

XTs regularly for sake at less than £15 on Chiggle/WainReaction.


 
Posted : 13/09/2019 10:20 am
Posts: 41786
Free Member
 

Tbh ive not had problems with external BBs in years. Currently have shimano, gxp, gusset and hope on various bikes.

They all feel notchy and rough after a year or so but take at least as long again to develop any play.

Just seems a different way of failing compared to square taper which remained smooth right up untill they developed play or siezed solid (or bent, or snapped).


 
Posted : 13/09/2019 10:47 am
 jeb
Posts: 0
Full Member
Topic starter
 

Thanks guys, super answers !


 
Posted : 13/09/2019 9:02 pm
Posts: 0
Free Member
 

They all feel notchy and rough after a year? That's damning.


 
Posted : 14/09/2019 9:53 am
Posts: 12648
Free Member
 

That's the effect of water and grit. Same with lower headset bearings for me as I don't use mudguards so they get attacked by water.


 
Posted : 14/09/2019 11:40 am
Posts: 25922
Full Member
 

Saint here

Longer cups so they don't strip/wear threads when you forget about them for a year

Whatever you get, I'd also always open up and pack with heavy grease - I leave grease round the outside of the seals too


 
Posted : 14/09/2019 11:49 am
Posts: 0
Free Member
 

I'd just go Shimano, but make sure you get one that fits your crank, there has been small changes. If it's an older crank your only options are probably Deore or Tiagra (BB52 and BB-RS500).
A buddy of mine tried to use a newer Ultegra BB (that requires the adapter for the wrench) with an old Tiagra crankset and it wasn't a good fit.


 
Posted : 14/09/2019 11:51 am
Posts: 25922
Full Member
 

Oh, wait - nobody's said - road and mtb are different widths and not interchangeable. You need the right "type"


 
Posted : 14/09/2019 12:59 pm
Posts: 11605
Free Member
 

The newer type brackets just use a different tool for fitting, I had to do a lot of reading to check compatibility with my SLX cranks, widths are still exactly the same.

And no, don't mix road and MTB as the axle lengths don't allow it.


 
Posted : 14/09/2019 5:14 pm
Posts: 12648
Free Member
 

And no, don’t mix road and MTB as the axle lengths don’t allow it.

Not correct. The BBs are suitable for both 68 and 73 width bottom bracket shells and the plastic tube in the middle of the cups is long enough for 73 but can go as short as 68 as the cup slides down it.


 
Posted : 14/09/2019 6:55 pm
Posts: 0
Free Member
 

I have XT, but would get Saint if I had to choose again as it uses the more common 44 mm tool compared to the weird 41 mm XT uses (no, the plastic adapters break easily). It's gold though.


 
Posted : 14/09/2019 7:58 pm
Posts: 11605
Free Member
 

Kerley I can show you a comparison between my mtb and road cups if you like, the road bracket has a different thickness of bearing shell and shorter thread insertion meaning you can't just swap the plastic spacer between the two. I should know because I tried to use an Ultegra bracket to fit my SLX cranks et and it came up hilariously short as its designed for a shorter axle length.

Alternatively you can read this fuller explanation https://bicycles.stackexchange.com/questions/47334/difference-between-road-mountain-hollowtech-ii-bottom-brackets


 
Posted : 14/09/2019 9:54 pm
Posts: 12648
Free Member
 

thanks for correcting me squirrelking. I have swapped between the two with no problem but guess I just used more spacers on the MTB cranks with road BB so it worked fine. The BBs are still marked as 68/73 so the plastic spacer will still be fine though as it can accommodate 5mm difference in BB shell.


 
Posted : 15/09/2019 8:23 am
Posts: 11605
Free Member
 

The MTB spacer covers both as even on a 68mm shell the added cup spacers bring it back out to 73mm (plus e mount).

It is possible to swap between the two but it's a bit of a bodge and you're not going to get the correct spacing for mtb unless you use different cup spacers


 
Posted : 15/09/2019 1:57 pm
Posts: 12648
Free Member
 

It is possible to swap between the two but it’s a bit of a bodge

Wouldn't be the first time. You should have seen me installing external headset cups when I used to have frames that required them...


 
Posted : 15/09/2019 3:22 pm