Press fit bottom brackets

rockmonkeysc

I need to replace the bottom bracket in my Anthem
http://www.giant-bicycles.com/en-gb/bik ... 865/45505/

It's a press fit type so ideally I want something with replaceable bearings so I don't need to have cups pressed in and out every time they wear.
I was looking for a Hope bb but can't find one. Do they make one? If not what should I go for?
And what good reason is there for press fit bottom brackets?

cooldad

I don't think anyone's thought of a good reason yet. Only bad ones.

The Northern Monkey

Think its a bb86 isnt it?

I hate pressfit BB's, just because HT2 are easier to replace and simpler to install (although the BB86 isn't as much of an arse as the BB30).

stubs

RockmonkeySC wrote:

And what good reason is there for press fit bottom brackets?

Production reasons must take seconds to machine BB shell and shove a press fit in with a machine but take minutes cutting threads and assembling spacers and screwing a HT2 or Sq taper in. Seconds count when your assembling a gazillion bikes a year. My new bike has a PF30 BB and it looks like a large piece of engineering cack relying on a pair of shoddy flimsy looking plastic cups to hold the bearings, a solution only someone who doesnt ride a bike would come up with.

WindyG

I thought it had a BB92

Levi_501

As you all know there are several versions of press fit BB so getting the right one and the correct spacers is crucial.

Hope do make a PF41, both stainless steel and ceramic. It has a threaded centre tube, which appears to hold the bearing cups in place.

The Real World Racing BBs are very good, the best I found, although I have not tried the Hope. The biggest downside to the RWR is they are only available from them (USA) and you will likely get stung for VAT/duty.

Depending which type you have, Praxis also make some and a PF30 adaptor that converts to standard thread.

rockmonkeysc

How do I work out which type of press fit I have got?

majormantra

You have a Shimano standard pressfit for a mtb, so something like this:

http://www.chainreactioncycles.com/shim ... -prod61801

or slightly posher:

http://www.chainreactioncycles.com/shim ... -prod44225

There are a lot of numbers being tossed around in this thread, which stems from the fact that there's no standardised name for the Shimano pressfit system. Shimano further confuses the issue by talking about BB71 and BB91 which are product hierarchy designations (like groupset levels) NOT the names of different standards.

Essentially Shimano pressfits fit Shimano cranks (which have a 24mm spindle) into bottom bracket shells of 41mm diameter with a width of 86.5mm (road) or 89.5/92mm (mtb).

rockmonkeysc

MajorMantra wrote:

You have a Shimano standard pressfit for a mtb, so something like this:

http://www.chainreactioncycles.com/shim ... -prod61801

or slightly posher:

http://www.chainreactioncycles.com/shim ... -prod44225

There are a lot of numbers being tossed around in this thread, which stems from the fact that there's no standardised name for the Shimano pressfit system. Shimano further confuses the issue by talking about BB71 and BB91 which are product hierarchy designations (like groupset levels) NOT the names of different standards.

Essentially Shimano pressfits fit Shimano cranks (which have a 24mm spindle) into bottom bracket shells of 41mm diameter with a width of 86.5mm (road) or 89.5/92mm (mtb).

Thanks. That makes sense.
The review of the BB91 at the bottom of the page is very strange. Not too sure what he was on when he wrote that but it's not a normal review of a bottom bracket!

majormantra

Blimey, I see what you mean.

some nutter wrote:

Well after being a proud owner of a Shimano overhead,fast releasing fishing spool during my youth angling years,I was absolutely delighted in learning that I will need a Shimano BB91 press fit bottom bracket for my new 3K carbon fiber fluff magnet.
Upon purchasing my bottom bracket from CRC,I showered,shaved and dressed in my favourite,faithful Shimano fishing polo shirt..As this was going to be the catch of the week!...Order complete,job done.
I've been smashing the pants off this senorita since Jesus was in his virgin mothers placenta....And I'll tell you what,God himself has nothing on this.
As Cher Lloyd would say,"this is for all the haters!"..Change frames and get a BB91 compatible bottom bracket set up!Make sure you order it from CRC!They make the invention of sliced bread seem irrelevant.

stubs

Can I have a pint of what hes on

rockmonkeysc

stubs wrote:

Can I have a pint of what hes on

I think it comes in grammes rather than pints.

majormantra

For future reference I've expanded my post above into a blog post. I hope y'all are pleased you inspired me:

http://thesetbackpost.com/mechanics/shi ... of-things/

stubs

This is a handy guide to sizes and applications http://problemsolversbike.com/files/tech/Bottom_Bracket_Standards_Reference.pdf

cloudynights

Hope press fit bottom bracket won't fit in a Anthem drive side will but the non drive side won't,it hits a chamfer on the Anthem,and won't go fully in

Clank

Anything in the Chris King armoury that would fit? They do a rake of fittings for various standards.

Won't be the cheapest but....



I've come to the conclusion press-fit BBs are fitted with the express purpose of ticking people off! Give me threaded any day of the week.