[Closed] Confused about press fit BBs

My dad has a 2012 defy and we put a Shimano BB91 BB in it that I had in the parts bin from my old lapierre.

They are unfortunetly Sh!te BB's

my confusion over them, is why anyone would think them a good idea in the first place... 😳

Zippy +1. Got Lapierre with one, they're a pain in the @rse.

Will this work?? Whats the diameter of your BB shell?

[url= http://problemsolversbike.com/products/eccentric_46_bottom_bracket/ ]clicky (problem solver)[/url]

links 1&3 are the same

links 2&4 are the same

links 1&3 are without a central sleeve

links 2&4 are with a central sleeve

all will fit a MTB setup

Ok Z1ppy & cooie, have your fun, but I didn't choose to have press fit - it came with the bike, and now I'm stuck with it!

Singlespeed shep, as links above, there's even two versions of BB91 on offer - 41A and 42A. And I'm afraid the eccentric BB is not really what I'm after, that's for adjusting chain tension on a single speed.

Still confused - clarity and sympathy required - yes I know, shouldn't have come to STW 😛

Ah, reggiegasket, now we're getting somewhere! You'd think so from the pictures, but lurking in the detailed descriptions there's some other differences like 3 is for 42mm diameter shells and 4 is for 41mm diameter shells. Also 1 & 2 seem to be SLX/XT level whereas 3 & 4 are XTR.

The plot thickens...

I'd like to say i'd never buy a frame with a press fit bb, but i fear that's the direction bike manufacturers are taking for some reason. 😐

Not poking fun, l share your confusion 😉 Just did a google search for bb71 and came up at several stores including Merlin for £24.95. HTH 🙂

wors - Member
I'd like to say i'd never buy a frame with a press fit bb, but i fear that's the direction bike manufacturers are taking for some reason.

Allows a bigger, stronger, stiffer junction between seat tube & downtube, no and threads to strip.

They're no better or worse than standard HT BBs, in my experience. And fitting/removing them isn't that much hassle.

I don't see the issue. Nobody complains about press-fit headsets.

I got introduced to PF30 this morning. My head hurts.

Nobody complains about press-fit headsets.

I know but they aren't in the firing line of all the shite. They probably are fine. At least with HTII you can still go back to sq taper 😀

devil in the details...

BB71 or BB91-41A should be fine. I've had the 91 in my hands, and fitted one, and it looks like a basic BB so I wouldn't sweat on the 71/91 issue.

I don't think the issue is 'press-fit' per se.

Rather the longevity of any BB is down to the quality of the BB unit itself, particularly the sealing. And the quality of the installation.

The Shimano pressfits look pretty basic to me - I've fitted a few now and smashed a few apart when taking them out... The higher end ones like Enduro are more serious units.

PF30? ANOTHER standard for BBs. Oh joy, well I suppose we were due for another one. 🙄

Singlespeed shep, as links above, there's even two versions of BB91 on offer - 41A and 42A. And I'm afraid the eccentric BB is not really what I'm after, that's for adjusting chain tension on a single speed.

Yep am aware of what it is "for" but if it fits your frame it would enable you to use a conventional BB. Where there are more options at different price points that are also easier to fit and remove.

It would also give you the opportunity to change the BB height on your frame.

reggiegasket - Member
I don't think the issue is 'press-fit' per se.

Rather the longevity of any BB is down to the quality of the BB unit itself, particularly the sealing. And the quality of the installation.

The Shimano pressfits look pretty basic to me - I've fitted a few now and smashed a few apart when taking them out... The higher end ones like Enduro are more serious units

I'd agree. Cheap BBs are shit. Better ones cost more, but last better.

Press-fit is a red herring really, just that press-fit bikes tend to come with cheapo BBs.

I'd just go with link 2, it's XT level and lasted 18 months in my Lapierre. The only hassle with press-fit is it means new tools if you want to do it right, there's plenty of bodge/DIY tool options though. I don't see why it's a more flawed design vs external cups. The Lapierre issue is with water collecting in the BB shell (having come in from elsewhere on the frame not through the BB), if your shell has a drain hole in the BB shell you shouldn't get the issue.
Not saying we really needed another BB standard but at least press-fit has some logic behind it.

They're no better or worse than standard HT BBs, in my experience. And fitting/removing them isn't that much hassle.

I don't see the issue. Nobody complains about press-fit headsets.

The press-fit BB on my Stumpjumper FSR doesn't seem great to be honest. After a wet ride, it tends to get really stiff & need riding for a while to loosen off. I don't even get to ride the bike that often, so hope it will last a long time, but am not expecting it to.

Fitting/removing them doesn't seem too difficult, but the proper tools to do it seem quite a lot more expensive than something like a HTII tool.

Press-fit headsets are a bit different. You press the cup in & that's it. The Cane Creek S3 on my Inbred has standard bearings that are easily replaced. The cups don't need to come out. I suspect I will still be using them in the same frame for years to come.
And headsets as already mentioned, aren't in the firing line of all the muddy water & crud that gets thrown up down by the BB.

Isn't the BB91-42a a specific Specialized thing?

Fitting the PressFit is easy enough with threaded rod similar to DIY installation of headsets. Still I'm thinking of getting the proper removal tool (from Park, Enduroforkseals or something from tool shop) as previous removal with large screwdriver was bit faffy as the BB is not a plain tube on my bike.

PressFit BB must be great solution for manufacturers but does it have any benefits for the rider? Mine lasted only about a year (HT BB lasted about 2 years in my riding).

Ok, so the fog is clearing, looks like the BB91-41 from Bike 24 is the XTR version and will fit, otherwise there's a BB71 at Merlin (but for some reason I can't open the web page at the moment). I'd prefer to use CRC or Bike 24 as its part of a larger order, and I'm sure one of the CRC ones must be a BB71 but they just don't label it as such - ever get the impression the guy who puts the descriptions and pictures up on the web site doesn't know anything about bikes - there's some shocking mislabelling!

I don't think you'll find it much cheaper than the bike24 one.

A lot of the UK BB91s are £40+ (On one have some too)

Yeah, Bike24 seems to have some of the best prices on Shimano & SRAM bits & pieces at the moment - kinda makes up for the PITA it is to pay - last time I had to send them a scan of my credit card!

Rose has them bit cheaper 17,90e but they are have limited availability (whatever that means).
Link: http://www.roseversand.com/article/shimano-bearing-shells-sm-bb91/aid:348836

Aaaargh! Just when I thought I'd got it sorted I come across this on Wiggle...

[url= http://www.wiggle.co.uk/shimano-pressfit-bottom-bracket-with-inner-cover/ ]Wiggle BB91-41[/url]

Description says "PressFit bottom bracket designed specifically for road bikes" but the picture clearly shows a BB91-41. Wrong description, wrong picture, who knows....

Have you seen these? 😛
http://clee-cycles.co.uk/esite/P1047/product

I like these:

[img] [/img]

And they only last forever 😆 What was the question?

The wiggle one has a pic of an mtb BB but the description of a BB86 road BB. I suspect the pic is wrong. I've seen plenty of ads for road BB86 BBs where they've used the MTB pic. The world is run by a range of competencies...