T47 BB 68mm inboard or outboard?

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wilwil
Posts: 694
Joined: Thu Sep 23, 2010 5:47 pm

by wilwil

My next frame is is Ti with T47 BB 68mm. Im using Campag UT. Im thinking C-Bear as I still dont think Campag make the correct cups yet. What determines whether I need inboard or out board bearings?

bobones
Posts: 1271
Joined: Mon Aug 12, 2013 11:19 am

by bobones

The distance between the crank bearing journals and the frame shell width determines if bearings are inboard or outboard. For example, a BB30 crank on a 68 mm wide frame uses inboard bearings whereas SRAM DUB, with its wider bearing stance, needs outboard. I don't know about Campag UT, but I suspect it will use outboard bearings on a 68 mm wide frame with inboard bearing being used with wider frame standards like BB386EVO.

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TobinHatesYou
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Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

Outboard.

ipenguinking
Posts: 743
Joined: Sun Jan 09, 2005 5:14 pm
Location: Sunny So Cal

by ipenguinking

Outboard BB for T47 68mm bottom bracket shell

wilwil
Posts: 694
Joined: Thu Sep 23, 2010 5:47 pm

by wilwil

Just found out I can have 68 or 86 so have decided to go with 86 internal.

gorkypl
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Joined: Fri Sep 21, 2018 9:31 am
Location: Poland

by gorkypl

Campagnolo makes T47 cups (both 68 external and 86 internal), but only for Ekar cranks.

Fuji Cross 1.5 - Shimano 105 5800 | Cinelli Superstar Disc - Record 12s | Custom steel Karamba - Ekar 13s

wilwil
Posts: 694
Joined: Thu Sep 23, 2010 5:47 pm

by wilwil

gorkypl wrote:
Tue Dec 07, 2021 2:14 pm
Campagnolo makes T47 cups (both 68 external and 86 internal), but only for Ekar cranks.
Yeah its a bummer. Are T47 BBs that rare on road bikes?

gorkypl
Posts: 529
Joined: Fri Sep 21, 2018 9:31 am
Location: Poland

by gorkypl

wilwil wrote:
Tue Dec 07, 2021 3:47 pm
gorkypl wrote:
Tue Dec 07, 2021 2:14 pm
Campagnolo makes T47 cups (both 68 external and 86 internal), but only for Ekar cranks.
Yeah its a bummer. Are T47 BBs that rare on road bikes?
It's a fairly new standard, and got some popularity only recently. Next gen Campy road group should/will be compatible with T47.

Fuji Cross 1.5 - Shimano 105 5800 | Cinelli Superstar Disc - Record 12s | Custom steel Karamba - Ekar 13s

ipenguinking
Posts: 743
Joined: Sun Jan 09, 2005 5:14 pm
Location: Sunny So Cal

by ipenguinking

I personally prefer 68mm bb shell with outbard bb for easier installation. The contact area between bb cup and tool is simply too small for 86 internal. I can forsee difficulty removing the bb after a year or two.

wilwil
Posts: 694
Joined: Thu Sep 23, 2010 5:47 pm

by wilwil

ipenguinking wrote:
Tue Dec 07, 2021 6:15 pm
I personally prefer 68mm bb shell with outbard bb for easier installation. The contact area between bb cup and tool is simply too small for 86 internal. I can forsee difficulty removing the bb after a year or two.
I have a version of it on my C64 and you have to be careful. I put a piece of polythene bag between tool and cup. Doesn't help that the tool is plastic.I also use Park Anti seize. Came out okay after a year.

wilwil
Posts: 694
Joined: Thu Sep 23, 2010 5:47 pm

by wilwil

gorkypl wrote:
Tue Dec 07, 2021 5:08 pm
wilwil wrote:
Tue Dec 07, 2021 3:47 pm
gorkypl wrote:
Tue Dec 07, 2021 2:14 pm
Campagnolo makes T47 cups (both 68 external and 86 internal), but only for Ekar cranks.
Yeah its a bummer. Are T47 BBs that rare on road bikes?
It's a fairly new standard, and got some popularity only recently. Next gen Campy road group should/will be compatible with T47.
January 2023 (not a typo) the cups are due in to my Campag shop! They are on order. Maybe different in the rest of the world

ipenguinking
Posts: 743
Joined: Sun Jan 09, 2005 5:14 pm
Location: Sunny So Cal

by ipenguinking

Anyone sees potential compatibility and chainline problem with the following combo?
--Frame is a custom titanium with T47 68mm bottom bracket shell
--DA 9200 group
--Power2Max NG Rotor ALDHU Carbon 30mm 4-bolt Shimano
--Rotor Aero 110x4 Roung Rings 2x (or 9100 rings)
--Wheel Mfg T47 Outboard BB for 30mm Cranks

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wheelsONfire
Posts: 6283
Joined: Mon Jul 07, 2014 8:15 am
Location: NorthEU

by wheelsONfire

ipenguinking wrote:
Fri Dec 10, 2021 3:42 am
Anyone sees potential compatibility and chainline problem with the following combo?
--Frame is a custom titanium with T47 68mm bottom bracket shell
--DA 9200 group
--Power2Max NG Rotor ALDHU Carbon 30mm 4-bolt Shimano
--Rotor Aero 110x4 Roung Rings 2x (or 9100 rings)
--Wheel Mfg T47 Outboard BB for 30mm Cranks
What frame is it (just to satisfy my curiousity).
Why would there be an issue with chainline?
You use disc brakes you go for the longer axle for Aldhu.
Bikes:

Ax Lightness Vial EVO Race (2019.01.03)
Open *UP* (2016.04.14)
Paduano Racing Fidia (kind of shelved)


Ex bike; Vial EVO D, Vial EVO Ultra, Scott Foil, Paduano ti bike.

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ipaul
Posts: 231
Joined: Mon May 30, 2005 2:06 am

by ipaul

https://youtu.be/rTNm-YPkeOc This may help answer your question. At least a little.
:P

by Weenie


Visit starbike.com Online Retailer for HighEnd cycling components
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