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external type bb,s questions
http://www.retrobike.co.uk/forum/viewtopic.php?f=41&t=144328

Author:  MAXTHEROTTI [ Tue Apr 05, 2011 3:32 pm ]
Post subject:  external type bb,s questions

hi all

how do the new type bb,s work
any special tools needed to fit them??

anything else i need to know??

thanks rob

Author:  stew-b [ Tue Apr 05, 2011 3:34 pm ]
Post subject: 

you need one of these- http://www.amazon.co.uk/gp/product/B001 ... ss_product
great system and very easy to work on :)

Author:  MAXTHEROTTI [ Tue Apr 05, 2011 3:54 pm ]
Post subject: 

nice to know 8)

Author:  WD Pro [ Tue Apr 05, 2011 4:28 pm ]
Post subject: 

I kept clear of those type of spanners as I was concerned about the laser cut / stamped edges being 'sharp' and damaging the BB finish - I dont know if its a genuine problem or not though :? probably just me being a bit OCD ... :oops: :lol: but how do you set the torque ?

I used one of the socket types - fitted really well and no marking of the finish at the correct torque :

Image

Cheers,

WD :D

Author:  giant-one [ Tue Apr 05, 2011 4:43 pm ]
Post subject: 

Try this.
http://www.youtube.com/watch?v=UAqAanDsAKA :wink:

Author:  stew-b [ Tue Apr 05, 2011 5:19 pm ]
Post subject: 

WD Pro wrote:
I kept clear of those type of spanners as I was concerned about the laser cut / stamped edges being 'sharp' and damaging the BB finish - I dont know if its a genuine problem or not though :? probably just me being a bit OCD ... :oops: :lol: but how do you set the torque ?

I used one of the socket types - fitted really well and no marking of the finish at the correct torque :



Cheers,

WD :D


the spanner i got was very well finished with no sharp edges,torque wise as seen in the listed video,they dont need to be silly tight and you can easily nip it up tight enough with the spanner type.bonus with the one i showed is you also get the plastic tool to remove the crank centre cap.

Author:  02gf74 [ Tue Apr 05, 2011 5:27 pm ]
Post subject: 

stew-b wrote:
great system and very easy to work on :)


hmm, no easier or harder to work on than the one piece sealed bottom bracket.

some say the bearings last nowhere near as long.

Author:  stew-b [ Tue Apr 05, 2011 5:46 pm ]
Post subject: 

02gf74 wrote:
stew-b wrote:
great system and very easy to work on :)


hmm, no easier or harder to work on than the one piece sealed bottom bracket.

some say the bearings last nowhere near as long.


hmm much easier! no more crank extractors needed! :)

Author:  cyfa2809 [ Tue Apr 05, 2011 5:57 pm ]
Post subject: 

my spanner one wasnt too bad
made by kenli :?
was cheap enough but cant find link now
didnt mark it much (but now has due to being used many times)
i didnt figure out how to use the socket ones until recently but the spanner has the added benfit of being able to be used to get one of the cranks arms off - no crank tool

Author:  WD Pro [ Tue Apr 05, 2011 9:11 pm ]
Post subject: 

I think my xtr has a different tool for removal than the one you refer to but the socket I have is double sided and has a torx style fitment on it - I never sussed out what it was for :? It then has a hex drive in the middle which is driven by a removable (supplied with tool) hex key socket which is standard 3/8" drive :D

WD :D

Author:  cyfa2809 [ Tue Apr 05, 2011 9:48 pm ]
Post subject: 

the torx type bit is for certain crank bolts i think

Author:  WD Pro [ Tue Apr 05, 2011 9:50 pm ]
Post subject: 

This is the type I have :

Image

Mines not ice toolz but it is nigh on identical :D cheap off eBay ;-)

WD :D

Author:  jetstream [ Thu Apr 14, 2011 12:55 pm ]
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its recommended that the frame shell is re-faced prior to fitting the cups, so that the bearings sit squarely to the crack axle. Needs a special tool to do it, so its probably a job for the LBS

Author:  WD Pro [ Thu Apr 14, 2011 1:10 pm ]
Post subject: 

Yes, I had read this before I fitted and made the decision to do so (even though the BB shell was fully CNC’d). I was fortunate enough to have free access to the correct park tools 8) It just cost me a burger and a pint in the pub after ;-)

WD :D

Author:  cyfa2809 [ Thu Apr 14, 2011 1:16 pm ]
Post subject: 

that said, surely the cups will sit straight when done up to the correct torque?

Author:  MAXTHEROTTI [ Thu Apr 14, 2011 1:52 pm ]
Post subject: 

got a superstar spanner for mine in the end works well enough

but i would go for a cup type next time :wink:

Author:  cyfa2809 [ Thu Apr 14, 2011 1:55 pm ]
Post subject: 

why so?

Author:  MikeD [ Thu Apr 14, 2011 2:01 pm ]
Post subject: 

WD, that "Torx" bit fits the plastic preload cap on non-XTR Shimano cranks. XTR has a preload ring behind the LH crank arm, all the others have a cap threaded into the end of the axle, a bit like a headset :)

Author:  MAXTHEROTTI [ Thu Apr 14, 2011 2:07 pm ]
Post subject: 

cyfa2809 wrote:
why so?



so you can use a torque wrench on it and it grips all the way round the bb cup too :wink:

Author:  cyfa2809 [ Thu Apr 14, 2011 2:09 pm ]
Post subject: 

MikeD wrote:
WD, that "Torx" bit fits the plastic preload cap on non-XTR Shimano cranks. XTR has a preload ring behind the LH crank arm, all the others have a cap threaded into the end of the axle, a bit like a headset :)


i thought it was for certain axle bolts?
i.e hollowtech cranks bolts - just one

Image

Author:  MikeD [ Thu Apr 14, 2011 2:17 pm ]
Post subject: 

Yes, those are the preload caps in question. Except those are daft alloy ones rather than nice, safe, can't-be-overtightened plastic ones.

Author:  cyfa2809 [ Thu Apr 14, 2011 2:28 pm ]
Post subject: 

MAXTHEROTTI wrote:
cyfa2809 wrote:
why so?



so you can use a torque wrench on it and it grips all the way round the bb cup too :wink:


ok some good points there, cheers for the info



the preload caps above are actually titanium

so preload/axle bolt = same thing 8)

Author:  MikeD [ Thu Apr 14, 2011 3:48 pm ]
Post subject: 

Titanium? Even more dafterer.

I'll probably get accused of pedantry pointing this out, but a preload cap is not the same as a crank bolt. A crank bolt holds the crank on, the preload cap does the same thing as the top cap on an Aheadset.

Author:  cyfa2809 [ Thu Apr 14, 2011 3:55 pm ]
Post subject: 

no no this is fine
i was expecting this

err so what holds the cranks on then? :?

Author:  WD Pro [ Thu Apr 14, 2011 4:11 pm ]
Post subject: 

cyfa2809 wrote:
that said, surely the cups will sit straight when done up to the correct torque?


They will sit straight to the frame - but they need to be straight / parallel to each other :D

Bad BB shells / un-parallel cups are believed to be the main mode of premature failure of this type of bottom bracket.

WD :D

Author:  WD Pro [ Thu Apr 14, 2011 4:17 pm ]
Post subject: 

MikeD wrote:
WD, that "Torx" bit fits the plastic preload cap on non-XTR Shimano cranks. XTR has a preload ring behind the LH crank arm, all the others have a cap threaded into the end of the axle, a bit like a headset :)


Thank you :D

This is the first time I have had (or even looked at) this kind of BB - I hadn’t really realised there were different methods from Shimano :oops:

For anyone interested in how 970 works :

Image

WD :D

Author:  cyfa2809 [ Thu Apr 14, 2011 4:41 pm ]
Post subject: 

do the cups fail that way then?


oh i see now that all makes sense!

Author:  The Ken [ Thu Apr 14, 2011 5:39 pm ]
Post subject: 

I just make mine hand tight, only use the spanner to remove them, bearings go fast if preload is too much but superstar have started doing angular bearings to deal with this.

I use mine with my bullseyes - I have to side load them to make them fit as it is a bit tight - cheap bearings last 6 months - hope last over a year but cost twice as much. I'm hoping the superstar bearings solve my wear issues.

Author:  cyfa2809 [ Thu Apr 14, 2011 11:58 pm ]
Post subject: 

have you cross checked the bearing code for cheap ones in ebay?

Author:  MAXTHEROTTI [ Fri Apr 15, 2011 6:53 am ]
Post subject: 

WD Pro wrote:
MikeD wrote:
WD, that "Torx" bit fits the plastic preload cap on non-XTR Shimano cranks. XTR has a preload ring behind the LH crank arm, all the others have a cap threaded into the end of the axle, a bit like a headset :)


Thank you :D

This is the first time I have had (or even looked at) this kind of BB - I hadn’t really realised there were different methods from Shimano :oops:

For anyone interested in how 970 works :

Image

WD :D



yeah my hone have a plastic cap to pull them into the bb 8)

Author:  haydnw [ Fri Apr 15, 2011 7:04 am ]
Post subject: 

Just as an aside, I recently had my first play around with an external BB, when the one on the bike I borrowed ground to a halt after some particularly muddy riding. It was easy enough to just knock the old sealed bearings out and get some new ones off eBay for about £2 a set. Bashed those in and it runs very nicely now. Not sure how long it'll last, but it was certainly a cheap and easy way of getting it back up to speed!

Author:  MikeD [ Fri Apr 15, 2011 10:39 am ]
Post subject: 

Quote:
err so what holds the cranks on then?


Pinch bolts on the LH crank.

Author:  The Ken [ Fri Apr 15, 2011 12:31 pm ]
Post subject: 

cyfa2809 wrote:
have you cross checked the bearing code for cheap ones in ebay?


Hope bearings are custom made and the size isn't freely available - the inner diameter is 1mm smaller as you don't use a tophat with them.

Author:  cyfa2809 [ Fri Apr 15, 2011 2:31 pm ]
Post subject: 

oh i see
well i guess if they are more expensive but last longer
it works out the same 8)

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