Press fit bottom br...
 

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[Closed] Press fit bottom bracket help!!

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Over the last few years i have built up a few frames that have had the traditional threaded bottom brackets and i never had much of an issue making everything work.

My new build is a press fit BB and its a bit of a pain. The bike shop i bought the frame from are not local but they fitted the BB shell and bearings and provided the rest of the kit which was a crinkled washer for the drive side and 4 washers for spacing along with dust seals for both sides.

Not a problem i thought 🙂 anyway when i initially fitted the X01 SRAM cranks there was a 3 - 4 mm gap between the drive side dust seal and crank spider. The crinkled washer is not even close to being tight. With all 4 washer on the drive side there is still a gap. Plus the cranks are not as smooth as they should be.

So obviously i am missing some piece of the puzzle.

The frame is a Turner RFX and looking on their website there should be no need for a conversion kit.

So i hand my small problem over to you. All help is appreciated 🙂


 
Posted : 06/12/2015 2:35 pm
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Is it BB or PF30 on that frame? If so there's an adjuster on the LHS crank arm to take up slack. has a tiny allen head bolt on it.


 
Posted : 06/12/2015 2:56 pm
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It's a PF30 and no there is nothing on the lhs crank arm. That's making sense. Can that adjuster be ordered separately?

Thanks for the help


 
Posted : 06/12/2015 3:10 pm
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Google image "sram BB30 x01 crank" and you'll see the adjuster in the picture of the left hand crank arm, black thing with 4 'tabs'.

It's a part of the crank. if, you've got a bb30 sram chainset that is? you've not got a converter in the frame and a GXP version of the crank by any chance?

Failing that, just "improvise" some more washers to take up the slack.


 
Posted : 06/12/2015 4:07 pm
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Ah nice one, trip to the bike shop tomorrow i think. 😀

I think there must be a spacer missing as the drive side crank will only go in as far leaving the 3 - 4 mm gap regardless. Something needs to space out that side a bit.

Head is pickled. Bloody standards 🙂 cheers


 
Posted : 06/12/2015 4:23 pm
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There's 2 length BB30 axles to further complicate matters. the longer one requires a spacer on the drive side to make it work but I remember it being more like 10mm thick.


 
Posted : 06/12/2015 4:31 pm
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Aye 🙂 i saw that. Not going to even try and figure it out any more.

Bike shop time. 🙂


 
Posted : 06/12/2015 4:34 pm
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Pf30 to gxp adaptor and pretend it never happened. 😆


 
Posted : 06/12/2015 5:29 pm
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The only thing standard about bottom brackets it the fact they're all bloody different.


 
Posted : 06/12/2015 5:32 pm
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OP, as above depends on the type. I watched this video yesterday as planning to finally build a bike myself, at least partially


 
Posted : 06/12/2015 5:33 pm
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johnnystorm - Member
Pf30 to gxp adaptor and pretend it never happened.

Ha, as if it was that easy 🙂


 
Posted : 06/12/2015 6:48 pm
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I'm stupidly late to the party here...last new bike - Stumpjumper Evo came with a PF46 or something. The axle of the SRAM crank has a 10mm spacer so it all fits together.

First thing I did was to ditch the SRAM cranks, shove in some Wheels Manufacturing axle bung jobbies and fit a set of XT cranks. Job done.

One thing that worries me a lot is that the BB is still the original SRAM unit, which was grumbly straight out of the shop. Fourteen months later and it hasn't died yet...

...New bike turns up this week and it's BB30. "Not a problem" I stupidly thought, "just fit some Wheels Mfg axle bungs and lob in a set of XT cranks".

Then I discovered it was BB92...

Grrr!


 
Posted : 06/12/2015 7:02 pm
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Finally i might have the answer

[url= http://www.ebay.co.uk/itm/Wheels-MFG-Multi-Adapter-BB30-PF30-on-GXP-Sram-Cranks-/151877416435?hash=item235c9975f3:g:M8gAAOSwI-BWOSTm ]These!![/url]

Another bloody £30 aaarrrrggghhhhhh


 
Posted : 06/12/2015 7:41 pm
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I thought they came with a few more BB spacers that go against the frame before you tap the pf in ?


 
Posted : 06/12/2015 7:52 pm
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Fitted the spacers and the drive side gap seems about right. But if I tighten the cranks up any more than a nip then there is resistance in the cranks. How bloody hard can it be.


 
Posted : 23/12/2015 12:14 pm
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I dislike them as well. For the first time in well over 15 years I am having bb/crank faff and crank coming off.

It transpires that even if you use a headset tool to press them in, and tap through crank and axle, that is still not enough.

You have to batter the cranks in really, really hard to seat drive side down the last couple of mm, then use the plastic shimano pre-load thing under such tension you strip the thread, and finally you can clamp down uber tight.

A mm or two of intolerance = doesn't stay put. Grrrr.


 
Posted : 23/12/2015 12:57 pm
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Matt, cheers for that. Its actually getting me bloody annoyed. I'm not a complete nugget so this shouldn't be this hard. There is a lad who works in my LBS who spanners for a race team. Even he just shakes his head when i mention it.


 
Posted : 23/12/2015 2:32 pm
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I thought it was me too - and I am OK at spannering. 👿


 
Posted : 23/12/2015 3:46 pm
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I thought it was me too - and I am OK at spannering. 👿


 
Posted : 23/12/2015 3:46 pm

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