Press Fit Bottom Brackets

deer_dance

I've finally accepted that if I want a new bike it will have to be one with a press fit bottom bracket. Really wanted to avoid them but I've found only two 2015 carbon fibre frame bikes that are still sold with a threaded BB. Neither is quite what I'm after.

I'm interested to know...

Are any of the pressfit BB standards known to be more reliable than others?

Are any of the standards to be avoided?

thanks

86inch

I've not found an issue with Press fit BBs (PF30, BB30) although i've used Shimano chainsets with the BBs from Rotor that screw together in two halves inside the shell. No creaking, no fuss, no problems.

My Caad8 with standard BB30 pressed in bearings seems to be holding up and its my winter bike. I don't particularly like the FSA chainset on that so when the bearings fail, i'll be swapping it and installing a Rotor BB as above.

Pressfit certainly wouldn't put me off my frameset of choice.

sungod

it's not standards so much as quality/precision of manufacture/installation

it seems cf shells with/without a light alloy metal insert aren't a good starting point for systems that need close tolerances, some peole have no problem, others suffer from the start, which suggests tolerances aren't controlled tightly enough

my xcr frame is bb30, >5 years of silent operation, the bb shell is a lump of stainless steel that's been machined to the correct size

putting the same bb30 in a shell that's moulded/light/soft seems less reliable, if there're problems you can compensate using retaining compounds like loctite 609/641, but that makes install/removal fiddlier

for cf i'd look at pf30, bbright, osbb etc. which should work better with the slacker tolerances (or you can get a matching conversion sleeve to use threaded bb, but that adds weight)

arlowood

You could always opt for an adaptor to convert your pressfit frameset to HT2

for example

http://www.gbcycles.co.uk/p/75235/Praxis-Works-Shimano-BB-Converters?kw=&fl=1000&ci=44622655142&network=pla&gclid=CKjru8zth8YCFezMtAodJ2UAzA

or maybe

http://www.wiggle.co.uk/sram-pressfit-30-to-bsa-adapter/

I must agree with you that I'm not a great fan of pressfit BB's. Had one an a Trek Madone 5.9 and that needed a new bearing fitting at the first service due to slack tolerances.

That's why I am now a firm advocate of a good old steel frameset. OK I may suffer a weight penalty but I don't race and with my general fitness riding a steel frame with a fit and forget BB is just fine for me

keef66

I have a Scott CR1-SL and that has a BB86 press-fit BB. The frameset came with a factory fitted Shimano BB71-41. Used with 3 different Shimano chainsets it's been perfect for the past 2 years. Certainly no creaking or other untoward noises.

It doesn't go out in crappy weather though, and I'm not a heavy or powerful rider, so it hasn't been rigorously tested. But based on a sample of 1 I'd say the Shimano Press-fit BBs in a BB86 shell are reliable.

I wouldn't fancy faffing about with bearings that needed constant attention, grease, loctite and such like.

Monty Dog

There's a reason the likes of Shimano doesn't support BB30/PF30 and lots of manufacturers are dropping BB30/PF30 because it's a crock. BB86 and BB386 are still gaining popularity because they don't have the inherent design flaws. I've been running BB86/92 on a CX and MTBs and they remain reliable and creak-free, despite the occasional dunking. Lots of problems are due to poor manufacturing tolerances / poor installation.

mfin

PraxisWorks make adapters for BB30 that solve the creaking and tolerance problems (if they make one that works with the chainset you have or will have).
http://www.praxiscycles.com/conversion-bb/

johnmiosh

I have the Scott CR1. The factory fitted BB lasted 2100 miles. The current one is now at 2300 and has started to click on out of saddle efforts. Not too irritating yet, but close. I also have a winter bike, so it doesn't see the worst of the weather, but I have still replaced the headset bearing twice in the same time.

keef66

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19623551#p19623551]johnmiosh[/url] wrote:

I have the Scott CR1. The factory fitted BB lasted 2100 miles. The current one is now at 2300 and has started to click on out of saddle efforts. Not too irritating yet, but close. I also have a winter bike, so it doesn't see the worst of the weather, but I have still replaced the headset bearing twice in the same time.

I've lost track of mileage because I have 2 bikes and swap the Garmin between them. Probably done less than 2000 on the CR1. Headset is still fine too, but given your experience I'll be keeping an eye / ear on both.
When you replaced the BB did you go for the same Shimano one again? I wonder if the Dura Ace equivalent might be longer lasting; it's only £2 more...

johnmiosh

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19623562#p19623562]keef66[/url] wrote:

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19623551#p19623551]johnmiosh[/url] wrote:

I have the Scott CR1. The factory fitted BB lasted 2100 miles. The current one is now at 2300 and has started to click on out of saddle efforts. Not too irritating yet, but close. I also have a winter bike, so it doesn't see the worst of the weather, but I have still replaced the headset bearing twice in the same time.

I've lost track of mileage because I have 2 bikes and swap the Garmin between them. Probably done less than 2000 on the CR1. Headset is still fine too, but given your experience I'll be keeping an eye / ear on both.
When you replaced the BB did you go for the same Shimano one again? I wonder if the Dura Ace equivalent might be longer lasting; it's only £2 more...

I have three bikes set up on the Garmin and record the milage of any maintenance. (Very sad, I know)

Both the original and replacement were Dura Ace level, but since then an Ultegra has become available. I can't see any real difference between them. Both are currently very cheap at Ribble.

http://www.ribblecycles.co.uk/sp/road-track-bike/bottom-brackets-bottom-brackets-shimano-bb71-road-press-fit-bottom-bracket-cups-with-internal-cover/shimbtbr365

schlepcycling

I have a Scott Foil 15 which is a BB86 bottom bracket and so far it's done 3,500 trouble free miles

gloomyandy

I've got over 5600 miles on my Cervelo R5 which has a BBRight/PF30 BB. No problems at all.