Campy Ultra Torque Bearing Replacement

[jeremy.m...@gmail.com]

Hi all,

I have a 2008 Campagnolo Centaur UT CT crankset on my CX bike. I put
about 7 K km on it on the road over the summer, then did several muddy/
wet cross races in the fall. I recently noticed that the right side
bearing was siezed, probably because I put the bike away with water in
the BB shell.

I removed the crank, and pulled the bearings with a pulley/bearing
extractor. I discarded the original, siezed bearings, and ordered
replacement 6805 RS bearings from an online retailer. I received the
repacement bearings and pressed them onto the crank half shafts.
They appeared to be fully seated. When I installed the cranks and
torqued the half shaft joint bolt, the bearings were obviously
overloaded by axial preload, and the crank can did not turn
freely.

It seems to me that either:

1) the bearings are not fully seated on their races

or

2) the replacement bearings are thicker than the original campy
bearings.

I am fairly certain that 1 is not the case-as I seated the bearings
with as much force as I feel comfortable using. The bearings I
installed measure 24.8 mm ID x 36.8 mm OD x 6.5 mm thick, using my
calipers.

Can anyone confirm the size of the original campy bearings? The bike
frame BB was faced and chased before the initial crank installation,
and the cranks spun freely at that time.

Thank you for any insight or ideas,

Jeremy

[lh...@planet.nl]

On 10 feb, 01:21, jeremy.maclen...@gmail.com wrote:
> Hi all,
>
> I have a 2008 Campagnolo Centaur UT CT crankset on my CX bike.   I put
> about 7 K km on it on the road over the summer, then did several muddy/
> wet cross races in the fall.   I recently noticed that the right side
> bearing was siezed, probably because I put the bike away with water in
> the BB shell.
>
> I removed the crank, and pulled the bearings with a pulley/bearing
> extractor.   I discarded the original, siezed bearings, and ordered
> replacement 6805 RS bearings from an online retailer.   I received the
> repacement bearings and pressed them onto the crank half shafts.
> They appeared to be fully seated.    When I installed the cranks and
> torqued the half shaft joint bolt, the bearings were obviously
> overloaded by axial preload, and the crank can did not turn
> freely.
>
> It seems to me that either:
>
> 1) the bearings are not fully seated on their races
>
> or
>
> 2) the replacement bearings are thicker than the original campy
> bearings.
>
> I am fairly certain that 1 is not the case-as I seated the bearings
> with as much force as I feel comfortable using.    The bearings I
> installed measure 24.8 mm ID x 36.8 mm OD x 6.5 mm thick, using my
> calipers.
>

I think you ought to get a new caliper. The ID/OD is 25/37 mm and I
think you need the smaller sized 6805 bearing which are 6 mm wide
instead of 7 mm. Wavy washer, seales in the right place?

> Can anyone confirm the size of the original campy bearings?  The bike
> frame BB was faced and chased before the initial crank installation,
> and the cranks spun freely at that time.

How wide is the BB shell?

Lou

[Qui si parla Campagnolo]

Like the other guy mentioned, you need 6mm width bearings. Not 7mm
(which is what standard 6805 bearings are). I have Campag bearings,
6mm, expensive tho, call if you wish to order them. make sure you use
the c clip on the RH bearing as well. If you cannot get the clip
on...cuz they are not 6mm.

vecchios.com

[jeremy.m...@gmail.com]

> Like the other guy mentioned, you need 6mm width bearings. Not 7mm
> (which is what standard 6805 bearings are). I have Campag bearings,
> 6mm, expensive tho, call if you wish to order them. make sure you use
> the c clip on the RH bearing as well. If you cannot get the clip
> on...cuz they are not 6mm.

Ok. Thanks for clearing that up. I wasn't aware that there were
two thicknesses of 6805 bearing-the ones I bought (all six of them!)
are too thick. Do I have to use "campagnolo" bearings, or is there
another option? I'm really starting to regret buying this crank....

[Lou Holtman]

jeremy.m...@gmail.com schreef:

Just the right size ;-)

> I'm really starting to regret buying this crank....

You blame Campagnolo not to measure the size of the removed bearings
before ordering new ones? Few bearings in bike equipment are standard size.

Lou

[russell...@yahoo.com]

http://store.bikebearing.com/shared/StoreFront/default.asp?CS=bearings&StoreType=BtoC&Count1=180416285&Count2=97556710&CategoryID=28&Target=products.asp

http://www.wheelsmfg.com/index.php?option=com_content&task=view&id=477&Itemid=31

http://www.wheelsmfg.com/index.php?option=com_content&task=view&id=478&Itemid=31

http://www.vxb.com/page/bearings/PROD/25mm/Kit7850

http://www.vxb.com/page/bearings/PROD/25mm/Kit7758

http://elitecycling.com/page.cfm?PageID=55&action=details&sku=BB1685

http://www.bikeman.com/BB1685.html?utm_source=GoogleBase&utm_medium=GoogleBase&utm_campaign=GoogleBase

http://www.bocabearings.com/main1.aspx?p=product&id=15928&n=MR6805C-2BS/TP/W6/C3_#5_UDL/SRL

http://fairwheelbikes.com/hsc-ceramic-hybrid-bearing-p-1044.html

http://www.ebikestop.com/ceramic_grade_3_6805_sealed_bearing_25x37x6-BB1685.php

http://www.superflycycles.com/servlet/-strse-285/Detail $26.70.
Cheapest of the links.

[Qui si parla Campagnolo]

You aren't the first guy to think that all bearings of this ID and OD
are the same width also. 7900 BB bearings are 6mm as well, for info.

The last gent posted the places where these are available. We have
Campagnolo ones....

[jeremy.m...@gmail.com]

> The last gent posted the places where these are available. We have
> Campagnolo ones....

Thanks to everyone who responded. How much are the campag steel
bearings, Peter? I'm not sure I want ceramic bearings, regardless of
cost, and all the 6mm bearings I can find online are ceramic, or
ceramic hybrid.

[Qui si parla Campagnolo]

$25 per, Campagnolo bearings(from Campag).

I agree that ceramic are not worth the $, unless they are $25 per but
if they are that inexpensive, I would wonder about their quality.
There are crappy ceramic bearings as well.