Hollowtech II bearing upgrade or stock replacement?

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I like Skol

A Minging Manc...
While fitting a new chain and general cleaning around the chainset area today I noticed a little play in the BB. I also found that if I spun the chainset with no chain on there was a distinct bad bearing rumbling transmitted through the frame. Clearly the BB is past its best so I see little to gain from trying to strip and rebuild it.

As I see it there are two options-
  1. buy replacement SM-BB51 (£13.99) and tool (£9.99) and stick with stock items, or
  2. I spotted THESE GUYS who rebuild the existing cups with better bearings and are currently fitting the new bearing FOC if you send your old cups to them.
Option 2 is a little bit dearer and I would still need the BB tool but I like the idea of upgrading rather than just replacing. Has anyone else done this? I am dissapointed with the lifespan of the original, only about 15-16 months and a little over 3000 miles. Is this typical? Obviously I would like to improve on this considerably.
 
You can get the tool for £7 posted off ebay - quality hardly matters as you only use it infrequently.

My only thoughts re the bearing service is that they get rid of the shim between bearings and axle - if the bearing seizes for some reason then the wear goes onto the axle and you may then need a new chainset.
 

02GF74

Über Member
I am dissapointed with the lifespan of the original, only about 15-16 months and a little over 3000 miles. Is this typical? Obviously I would like to improve on this considerably.

there are stories like yours on them not lasting long - was your bike fitted with them from new?

coz if not, you need to have the BB refaced so the cups are parallel, misalignment causes rapid wear.
 
OP
OP
I like Skol

I like Skol

A Minging Manc...
there are stories like yours on them not lasting long - was your bike fitted with them from new?

coz if not, you need to have the BB refaced so the cups are parallel, misalignment causes rapid wear.
This is the original BB fitted by GT as standard but I reckon that doesn't guarantee the BB shell faces are not skewed.
 
OP
OP
I like Skol

I like Skol

A Minging Manc...
I don't quite get this Hollowtech II thing as Shimano seem to be quite rigid in linking specific BB's to specific cranksets. Will any Hollowtech II BB fit any Hollowtech II cranks?

Is THIS any better than my stock Deore? BB51 in terms of strength and longevity or is it simple badge engineering to fit the same bearings into a higher/lighter spec groupset?
 
Yeah any will do the job :thumbsup: I've interchanged Ultegra and DA BB's on road bikes, it's just the quality of bearings and overall weight that differs IMO. There is one school of thought that the cheaper end stuff lasts better than the high end stuff but I'm not so sure myself.

HTII, (or SRAM equivalent) is my preference all day long. Just be happy you don't have to contend with BB30 bearings and their pi$$ poor wear rate :wacko:
 

VamP

Banned
Location
Cambs
:eek: Just got around to Googling 'Chris King Hollowtech II' and the prices are a bit scary to say the least £100+ for a BB is not my idea of a good balance between quality and cost.


Oh no. Chris King is definitely high end.
 
OP
OP
I like Skol

I like Skol

A Minging Manc...
Well, replacement BB just suddenly gave up the ghost in the last week or so. Developed big play while still running fairly smoothly. To say I am dissapointed is an understatement as the bike has only just done another 3000 miles on this BB.

Luckily it was the other side this time so I have swapped the good, old cup in and also noticed the shims (as fitted from the factory) weren't allowing the cranks to but up to the bearing cups. I slipped in an additional thin spacer on the L/H side and this was enough to sort it. I am going to risk one last standard SM-BB51 and hopefully this one will last longer than 12 months now the spacer issue has been spotted.
 

fossala

Guru
Location
Cornwall
Chris king is not only going to last a long time, it also is full serviceable. They are also very much ethically driven as well. http://chrisking.com/pucks

My headset is CK and when my new bottom bracket wears out (it came "free" with my chainset) I will be replacing it with a CK one.
 

Crankarm

Guru
Location
Nr Cambridge
I heard some one who had bought CK hubs spent a fortune, the rear hub bearings failed before a year was up. Cost a fortune to buy and a fortune to replace. If you want quality then go for Hope hubs or BBs.

Wrt to HollowTech2 I have ridden nearly 8k on my Kona the last year which has an FSA chainset with Mega Exo bearing shells. There is very slight play in the drive side shell and I mean slight. It should last another 2-3k before needing replacement, so 10-11k miles is not bad imho.
 

02GF74

Über Member
3,000 miles on external BB is not that bad. the older sealed spindkle BB would do 2x that easily.

the other option is to take the cups apart and fit the new bearings - i have done this recently - google the web as there is a good description of the procedure.

also whenever fitting sealed bearings, prise off the seal and fully pack the bearings with grease.
 
U

User482

Guest
I believe that Hope BBs have replaceable bearings. Not had to do mine yet, though, which is a recommendation in itself.
 
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