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PressFit 30 BBs - w...
 

[Closed] PressFit 30 BBs - what do i need to know?

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[#7960814]

A bike i'm interested in comes with a PressFit 30 BB, i don't know anything about the PressFit systems (i only have external & square taper), but PF sets off alarm bells in my mind as i [i]think[/i] i've heard bad things about them on here.

So, pros & cons & opinions please.

Its a "SRAM PF30" if that helps.


 
Posted : 24/07/2016 10:58 am
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The SRAM ones are a bit rubbish.

Many companies make decent ones now. Rotor being one such company.

You can easily fit a 24mm shimano one that fits like a normal ht2 setup for generic cranks


 
Posted : 24/07/2016 11:11 am
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Specialized, perhaps?

I somehow managed to get eighteen months out of mine, when I removed the BB it was full of dust. SRAM don't have the best reputation for making BB bearings.

There are alternatives though, both Praxis and Hope have a BB to fit, depending on whether you wish to retain your 30mm cranks or swap to Shimano.


 
Posted : 24/07/2016 11:13 am
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Poorly sealed dirt and grit magnets.


 
Posted : 24/07/2016 12:24 pm
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You will become an expert at changing the SRAM ones!!


 
Posted : 24/07/2016 12:52 pm
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Found the sram BB's deformed after couple of removals & a bearing replacements, so went to Hope instead, had to change the bearing friday, it was a doddle.
Hope BB FTW!


 
Posted : 24/07/2016 12:54 pm
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They greatly simplify the manufacturing process.


 
Posted : 24/07/2016 2:04 pm
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They are shit. I got to the point where i was spending a fortune so sold it. I was going through them nearly every three months. Tried, SRAM, BSA, Wheels Manufacturing ones too. Next time i would swap it out for a praxis converter and HT2 straight away.

I now avoid bikes with PF30 BB's.


 
Posted : 24/07/2016 3:02 pm
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I have a road bike with BB30, my concern is that repeated bashing out of bearings (let alone replacing them) will very quickly deform the aluminium tube within the carbon frame, to the point where the bearings don't seat and the frame is shot. Chances?


 
Posted : 24/07/2016 3:06 pm
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Fit a hope one no more issues!


 
Posted : 24/07/2016 3:06 pm
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Have to say my Rotor one has been faultless, even through last winters gloop.


 
Posted : 24/07/2016 3:07 pm
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Ive no experience of the aftermarket conversions, my chsinset is Shimano so 24mm diameter not 30mm, I use a set of reducer cups. How does the Hope system work?


 
Posted : 24/07/2016 3:12 pm
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Not sure by what you mean, how does it work...Hope have a PF92 (PF42) that fits shimano chainset, it's what on my current bike.

[*]Options to suit either 24mm or 30mm crank axles
24mm crank axle versions available to suit BB92, BB89.5, BB86.5 and 100mm bottom bracket width for Fat bikes
30mm crank axle version available to suit 89.5, 92, 104.5, 107 and 121mm bottom bracket widths
Available with replaceable stainless or ceramic bearings for less friction and greater durability[/*]


 
Posted : 24/07/2016 4:29 pm
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Sorry, meant how do they fit into the BB shell? Is it a screw-together insert that holds external HT II bearings or something else?
I really dont want to wreck my road frame by warping the alu BB shell.


 
Posted : 24/07/2016 4:34 pm
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My Praxis has been fine so far – 18 months with quite a bit of sloppy riding last winter. Though if I had a choice, I'd go for a threaded BB. Easy to service, loads to choose from.


 
Posted : 24/07/2016 4:36 pm
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it's a screw-together insert that holds bearings

(PS: sorry for breaking the thread format buy using one of the thread tools)


 
Posted : 24/07/2016 4:52 pm
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So, in summary, it's a flawed system sorted by fitting a high end BB (Hope etc).


 
Posted : 24/07/2016 5:37 pm
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Yep, i really dislike these pressfit systems.


 
Posted : 24/07/2016 7:19 pm
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I've just removed 2 bearings from my Rotor PF300/24mm BB.

I'm hoping that fixes the noise that's developed over the past few rides. If not, it's obviously the fitting the shell, which likely means destruction for the BB itself.

If it's dead, i'm going to give this a try i think.

http://www.ebay.co.uk/itm/121921000935?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

How does the HOPE one thread on then ? E.g, you turn this one using the standard HT2 type BB tool, but the hope seems to be a completely round edge ?


 
Posted : 25/07/2016 6:22 am
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How does the HOPE one thread on then

You screw the two side together using an internal fitting on the Hope intallation tool, I bought one thinking I'd need it to remove the bearing but don't (Doh!). So get your LB to fit it...

[url= http://www.bikerumor.com/2013/02/26/frostbike-2013-hopes-new-threaded-press-fit-bottom-bracket/ ]top of this page.. tool and then how it fits into the BB[/url]


 
Posted : 25/07/2016 12:22 pm
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Ah yes, i recall now from my other thread...Sorry 🙂

Will wait and see if mine is bearings or shell creak in the next few days.


 
Posted : 25/07/2016 12:27 pm
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I have specialised bikes with PF30 and the SRAM ones don't like wet, crappy conditions. My latest one I knocked out just the bearings, ie reusing the plastic insert, and replaced them with ceramic verions. My old bikes ceramic Hope HTII BB were amazing and lasted years so I'm hoping for similar results, but without buying a full Hope ceramic bearing - time will tell...


 
Posted : 25/07/2016 11:39 pm
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sorry bit late to this thread. keep it short, there shit.


 
Posted : 26/07/2016 12:24 am