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  1. #1
    Climbin' Clyde
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    C-Bear OSBB >> Campy Adapter Install

    So, first off let me say I was pretty surprised to find that Specialized calls Campy UT "incompatible" with their carbon OSBB frames. Had no clue when I bought my 2011 S-Works Tarmac SL3 - I had planned to finally 'go Campy' on it, after two decades riding Shimano.

    Thanks to a post in the forum, I learned of the C-Bear OSBB adapter, and ordered one from Discount-Bike.de in Germany.

    No instructions were included with the adapter. I e-mailed C-Bear for information, but got a response in Flemish(?) about Mavic wheels. Guess I'm on my own!

    Here's how it arrived - aluminum BB sleeve, non-drive side cap, Super Record BB cones and C-Bear's ceramic bearings. All new to me - I've been a Shimano guy. A circlip in the 21st century? OK.



    I got the frame NIB off Craigslist, but thanks to this dealio from Specialized, I was on my own from the start. So WTH, I'm going Campy



    Here's my press. 3/4" threaded rod, whopper washers each side. Spacer sleeve on left is a section of Thomson seatpost I just cut off my mountain rig



    Here's the start. I slathered the adapter sleeve in Loc Tite 609. "Medium strength adhesive for cylindrical assemblies" - sounds about right, doesn't it?



    But - this was the toughest thing I've pressed by far. Headsets into steel, aluminum - not even close. 200 grain SWC's into .45 cases - easy schmeezy. It popped, it pinged, it took serious pressure. Totally freaked me out. I took the assembly apart probably 6-7 times to ensure everything was aligned. I was certain I was going to hear and feel - at once - the entire BB shell crush under the pressure I was exerting.

    Half way in, I knew there was no turning back. As soon as the drive side flange engaged, the pressure increased! I slathered grease on top of the Loc Tite - I needed all the help I could get.



    Finally, I got the thing in. Almost. Here's the non-drive side. Tough to tell from the pic, but it is flush and even with the carbon BB pipe in the frame.



    But here's the drive side. Still a ways to go - and hard to tell if its aligned or not.



    At this point, there's no gap left for the press to press against. I wailed away with a rubber mallet, but the adapter would no sink any further. So - I think its going to remain here. Not coming out, that's for sure. Triple checked the BB shell, scanning for damage or cracks, all looks good. Now, to wait for my Chorus group to fly in from Ireland.


  2. #2
    RoadBikeReview Member
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    Congrats on getting together. I think I would have abandoned Loctite after your first effort. Obviously the stack up of BB ID to C-bear OD is 'tight'. You could have also used some 600# paper on the OD of the press surfaces of the C-bear. Hopefully the considerable press doesn't close down the C-bear cups and you can get the bearings in there.
    As to interpreting foreign language website....I always use Bablefish...google it. Plug in the Flemish and you should get a close translation to English.
    Keep us posted on how the Chorus install goes.
    PS: as to getting it out....it can be done but it will take a pretty substantial effort. Some very deft dremmeling for notching and stacatto blows with a punch would probably work best. FWIW impact forces move stubborn parts a lot easier than dull press force...and if you don't care about destroying the C-bear on the way out and want to preserve the frame...likely the way to go. Me personally, I would have taken the C-bear collars down a bit with fine sandpaper to reduce press.

    PS: a further tip about installing your Chorus crank. To assess lateral stack up...first install the Chorus crank without wave washer. Measure the amount of lateral play or lash without the wave washer with some calipers. Next lay a small piece of wood over the wave washer on a table. Measure the width of the wave washer uncompressed. If you divide this quantity by 2, this should approximate the amount of lateral lash without the wave washer installed. When you install the wave washer, now you know that it is neither too little or too much compressed. If you need a bit more room laterally, abandon a rubber hammer. Place painters blue tape over the edge of the C-bear, then a block of wood over the flange of the C-bear sleeve end and use a 3 lb sledge to tap the sleeve in place. Rubber hammers don't work well for this type of application and wood will protect the flange.. This will knock the C-bear in place line to line with the carbon shell wall to eliminate all gapping and maximize lateral clearance...if you need it after performing the stack up check..
    Last edited by roadworthy; 05-29-2012 at 03:48 AM.

  3. #3
    Climbin' Clyde
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    Thanks Roadworthy. I went back and did a couple sharp smacks with a wooden block, the drive side flange is now seated as flush as its going to be. Still a little "daylight" at a spot or two, but I believe this is an imperfection in the frame mold.

    The C-Bear adapter is BSA threaded FWIW. I'd heard that it was Italian threaded, and the opposing forces helped keep the assembly tight, but this is not the case.


  4. #4
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    Quote Originally Posted by Sablotny View Post
    Thanks Roadworthy. I went back and did a couple sharp smacks with a wooden block, the drive side flange is now seated as flush as its going to be. Still a little "daylight" at a spot or two, but I believe this is an imperfection in the frame mold.

    The C-Bear adapter is BSA threaded FWIW. I'd heard that it was Italian threaded, and the opposing forces helped keep the assembly tight, but this is not the case.
    Savlotny,
    Mads is the forum expert on the C-bear sleeve and a smart guy technically. I believe if you do a search for 'Mads' you will find his username. You can PM him with any questions along the way. I believe Mads taught us the C-bear sleeve is available in both english and italian threads...and he suggested the Italian thread version which of course would require the Campy cups with Italian versus English thread.
    If yours is English thread then of course it would require the Campy English threaded cups....Campy cups as you know are available both ways...I have the English threaded cups on my SL3 Roubaix which has a threaded BB.
    I look forward to your results.
    Cheers.

  5. #5
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    c-bear osbb:specialized frame+ camp crank

    Hello, Sablotny:

    I came across your posting by accident. We should be more on top of comments from forums. As we are primarily setup for b2b, therefore we have no manual/instruction. However, contact us and we will try to answer your questions as best as we could.

    I went thru last week emails and could not find your mentioned email. Could u resend info(+ @ sign)c-bear.com. We usually replied pretty quickly.

    Normally, it is not necessary to use Loctite to install our bottom bracket into new frame.

    Any questions pls contact us. Of course, u can also call us 32 (0) 11 603 208. Now u have all our contact info.

    Aria
    c-bear.com
    Last edited by c-bear; 06-26-2012 at 12:14 AM.

  6. #6
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    OP should have checked that the final width of the BB with adapter installed was within Campy specs for an English BB - 67.2 - 68.8mm. http://www.campagnolo.com/repository...UK_05_2012.pdf
    Presumably by now the crank is installed though?
    There's sometimes a buggy.
    How many drivers does a buggy have?

    One.

    So let's just say I'm drivin' this buggy...
    and if you fix your attitude you can ride along with me.

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  7. #7
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    Quote Originally Posted by c-bear View Post
    Hello, Sablotny:

    I came across your posting by accident. We should be more on top of comments from forums. As we are primarily setup for b2b, therefore we have no manual/instruction. However, contact us and we will try to answer your questions as best as we could.

    I went thru last week emails and could not find your mentioned email. Could u resend (info@c-bear.com). We usually replied pretty quickly.

    Normally, it is not necessary to use Loctite to install our bottom bracket into new frame.

    Any questions pls contact us. Of course, u can also call us 32 (0) 11 603 208. Now u have all our contact info.

    Aria
    c-bear.com
    Aria,
    What is set up for 'b2b' mean?
    I understand the C-bear sleeve is well engineered, but not having some simple instructions available for installation is a pretty serious oversight in my opinon.
    Most that sell sleeves similar but not identical to yours offer installation instruction in PDF. It doesn't have to elaborate but you should offer this as a service to those that purchase your product.
    Cheers.

  8. #8
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    c-bear osbb:specialized frame+ camp crank

    Quote Originally Posted by roadworthy View Post
    Aria,
    What is set up for 'b2b' mean?
    I understand the C-bear sleeve is well engineered, but not having some simple instructions available for installation is a pretty serious oversight in my opinon.
    Most that sell sleeves similar but not identical to yours offer installation instruction in PDF. It doesn't have to elaborate but you should offer this as a service to those that purchase your product.
    Cheers.

    b2b = business to business
    It is not an oversight.
    c-bear is originally setup with focus on bike shops as our customers. We expect the bike shops to have the technical knowledge, support and training to properly mount our products. However, as Bart is an cycle enthusiast himself, he likes to assist fellow cyclists too if they choose to do the mounting themselves. It is a free world. We always try our best to assist when questions come in.
    Being a relatively new small niche market setup, our resources are limited, we like to concentrate on product development rather than manual development(which can be time and resources consuming to be done properly - actually when necessary and whenever we can, we do develop some very crude ones - check out our facebook page example).

  9. #9
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    Quote Originally Posted by c-bear View Post
    b2b = business to business
    It is not an oversight.
    c-bear is originally setup with focus on bike shops as our customers. We expect the bike shops to have the technical knowledge, support and training to properly mount our products. However, as Bart is an cycle enthusiast himself, he likes to assist fellow cyclists too if they choose to do the mounting themselves. It is a free world. We always try our best to assist when questions come in.
    Being a relatively new small niche market setup, our resources are limited, we like to concentrate on product development rather than manual development(which can be time and resources consuming to be done properly - actually when necessary and whenever we can, we do develop some very crude ones - check out our facebook page example).
    You and I disagree on this about best business practice including selling product to the public without installation guidance. A small investment in time to develop a simple installation procedure would save you product liability and $$$. Further your presumption that bike shops know how to install any BB let alone your specific product is false. Bike shops fail to install BB's correctly even with detailed instructions. I fix a lot of their mistakes. Further BB30 and PF30 continue to evolve and most major bicycle brands and Specialized in particular continue to evolve their position and service manual PDF's which advise bike shops best procedure for installation and service. Installation aka set up is huge in terms of BB performance. So I believe your position is an oversight.

    According to the OP, the interference of the C-bear sleeve within a S-works carbon shell BB is 'excessive and now a separate bike owner has come forward and agreed with the OP. Only your company can provide a tolerance of acceptability for installation without consequences to the shell resulting from excessive force for installation. Virtually 'all mfrs' that sell a product such as yours offer an installation PDF on their website.
    Good luck
    Last edited by roadworthy; 08-08-2012 at 08:25 AM.

  10. #10
    Climbin' Clyde
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    To follow up on some of these recent posts:
    1. I purchased the C-Bear adapter from Bike-Discount.de, from Vaetuning's link posted on another thread. There were no BSA/Italian thread options shown, but this was fine as the adapter comes with BB cups. As I would learn later, the adapter fit inside the BB shell is tight enough that I don't believe threading the BB cups will cause the assembly to 'undo' itself. (On a related note, after many years and 20+ Shimano BB installs, Shimano cups typically thread very tight and I've only used 'dots' of Loctite on them. These Campy cups thread relatively loosely. From Campy's installation videos, this also seems to be the case - loose threads typically combined with a heavy dose of Loctite).
    2. As the adapter is sold to consumers by a bike store, I assumed this meant for consumers to buy and install themselves. There is no mention made that these are for shop installation only.
    3. The high pressing force I experienced may be due to the Loctite I used. There were two decals inside the BB shell which I removed - I knew the tolerances would be tight, I just didn't realize how tight. Possibly if I had used only grease from the get-go, things would have gone more smoothly. However, if I used only grease, the adapter may be more prone to twisting when installing the BB cups. I don't know.
    4. My components should be arriving any day, then I'll complete the build. So far the adapter seems to work and be as advertised, but I would have appreciated instructions with the unit.


  11. #11
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    We are working on info on installation.

    Aria
    c-bear

  12. #12
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    Aria,

    Once you've completed your installation instructions, for the sanity of all the subscribers and readers of this thread, i wonder if you could either provide a link to it or post the details here please ?

  13. #13
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    Quote Originally Posted by bigmac View Post
    Aria,

    Once you've completed your installation instructions, for the sanity of all the subscribers and readers of this thread, i wonder if you could either provide a link to it or post the details here please ?
    Yesterday, I responded to bigmac's post the following reply but somehow did not get publicized. Here it is again.

    My apology for my tardiness.

    I have the rough structure of the installation instruction. However, it is not close to presentable yet. But for those who cannot wait, how about first review the crude instruction we posted on c-bear facebook and google+ pages:

    http://www.facebook.com/cbearCeramicBottomBracket (see posting on 22 March 2012)

    https://plus.google.com/100949116021004291585/posts (see posting on 17 April 2012)

    One guy from other another thread (SL4 Pro frame OSBB and campy ultra torque crank) describes ďFirst, the conversion kit consists of 2 parts - one long cylindrical sleeve, which is pressed into the OSBB from the right side of the frame.
    Furthermore the kit contains one plate / collar with a grove / recess machined into the inside, which goes towards the frame on the left side.

    When you have pressed the sleeve into the OSBB from the right side, you still need to pull the sleeve a little further to the left, which you can do by placing the collar against the OSBB on the left side, and then tightening the 2 ITAL cups - WHICH BOTH HAVE RIGHT HAND THREADS - therefore you are able to both pull the sleeve all the way into its place, and securing the collar to the sleeve in one operation, without the risk of only rotating the Sleeve!!Ē

    For new frame, no loctite/glue is necessary.

    Aria

  14. #14
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    install c-bear osbb campagnolo

    Quote Originally Posted by bigmac View Post
    Aria,

    Once you've completed your installation instructions, for the sanity of all the subscribers and readers of this thread, i wonder if you could either provide a link to it or post the details here please ?
    My apology for taking excessively long time to prepare an installation guide.
    Initially I planned to complete with video clip, which I arranged from day 1. With my reputation at stake, while still waiting for the video clip, I have to take backup plan B quickly. With permission from sablotny to use his photos, I now have an open-source installation guide available http://www.c-bear.com/en/osbb-en/cam...c-bearings.php. Any comment, suggestion, addition and/or correction are welcome. Interestingly, Martin (UK) suggested to freeze the sleeve to ease the insertion.

    Aria
    c-bear

  15. #15
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    Funny, I was just about to post a suggestion where you put the sleeve in the freezer before assembly. I don't think this have been mentioned before but I see you have it in the instructions. In addition you could also use a hair dryer and carefully heat upp the BB area.

    Instructions look good but shell width is actually 61mm according to Specialized and not 62mm.

    It seems like a very tight fit. What is the OD on the C-Bear sleeve, 46.?mm

  16. #16
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    Long post!

    OK, so I'm about to install my C-Bear sleeve. However I am a bit concerned about the tight tolerances described in previous posts. I hope someone can chime in and sort it out.

    As far as I know you divide fits into different categories. The following applies to steel shaftĖhole fits, but youíll get an idea of the tolerances compared to the sleeve we are discussing.

    Loose fit - Use for all possible hole - shaft applications where function will permit.

    Free Fit - Running fits with speeds of 600 R.P.M. or over and journal pressures of 500lbs/sqin or over. Wobble or shake between mating parts very slight. Part will turn and slide freely.

    Medium Fit - Running fits under 600 R.P.M and journal pressures under 600lbs/sqin and for sliding fits. Wobble or shake between mating parts noticed only on parts with short bearing length.

    Transitional Fit (Snug) - Closest fit which can be assembled by hand and necessitates work of considerable precision. Should be used where no perceptible shake is permissible and, where moving parts are not intended to move freely under a load.

    Interference Fit - Considerable pressure is required to assemble these fits and the parts are considered more or less permanently assembled. Bushings and similar uses.

    For all fits one can calculate the tolerances needed for the desired fit and working temperature, but for many common materials this has already been done and presented in tables.

    So for the interference fit and a 46mm/1.81inch hole the table give Interference Max-Min .0025 - .0005 inches. The sleeve is actually 0.1mm/.0039inch, so itís even tighter than the maximum recommendations for steel. I consider bringing it down to .0010 inches before even trying to press. If it turns out a sloppy fit Iíll just use Loctite 9466 A&B. This will be a permanent solution but so is the press fit I think. Maybe I'm overly concernd, but I just don't want to risk destroying the frame. What do you think?

    Also Iím including a pic on how to solve the problem with BSA cups. I want BSA cups because the drive side can unwind unless really tight with ITA threads. Friend of mine ruined the frame threads because he didnít notice the cup coming out on a ride. Just one less thing to worry about. Spanner hook was made from 3mm mild steel and ground to 2.5mm at the the hook to not interfere when tightening the cup.
    Attached Thumbnails Attached Thumbnails C-Bear OSBB >> Campy Adapter Install-hook-spanner.jpg   C-Bear OSBB >> Campy Adapter Install-shell-dia.jpg   C-Bear OSBB >> Campy Adapter Install-sleeve-dia.jpg  
    Black bikes are nice, but red ones are faster.

  17. #17
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    Hi Steffo,
    I will give you my technical opinion. Optimally there should be a very light press fit...very slight interference between .0005-.001" diametral interference.
    Specialized BB carbon hole has a tolerance and so does the C-bear sleeve...so there will be variance from part to part. The carbon BB hole is designed for plastic bushings which can tolerate more press because the bushings have a much lower modulus of elasticity (they compress aka elastically deform) much more than the C-bear sleeve. So press is critical. Too much press is no good and as you do, I believe the C-bear sleeve is oversized as your findings agree with the OP. The OP in my opinion applied too much force to press it together. Not his fault...but rather C-bear for having their nominal diameter too large as you show. They need to reduce the nominal diameter slightly. So I believe you are on the right track. Reduce the diameter of the C-bear sleeve by machining or even sanding by hand or turning the sleeve on a lathe or chuck it on a drill press, attach with an arbor etc... such that you reduce the diameter to very slight press. With a light press you are then free to use an agent like Locitite 641 to hold it together which is servicable and not permenant.. No reason to have a permanent solution. I believe the OP will struggle with getting his apart if he ever tries to which isn't the end of the world but needless really. With light press and green Loctite you can get it both together and apart fairly easily.
    I do believe the C-bear is the best solution for Sworks frames but C-bear needs to address this issue.
    Let us know how it goes.
    PS: I like your solution of slotting the sleeve flange to resolve the tightening issue with BSA which I agree is directionally correct and why English BB's basically superceded Italian BB's. I hope C-bear sees your proprosal and not only reduces sleeve diameter but also considers incorporating slots into future C-bear sleeves.
    Last edited by roadworthy; 08-08-2012 at 08:19 AM.

  18. #18
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    Thanks for the input Roadworthy!

    Here's what I did:

    I prepared the frame by removing the QC stickers and did some light sanding of the burrs around the screw hole. Then I clamped the sleeve between two washers and used a drill to spin it. With some 300 grit emery cloth cut in strips and a file to support and ensure a flat surface I carefully removed 0.07-0.08 mm. The final diameter before fitting was 46.02 -46.03mm. This is a press fit of approx .0008-.0011". I could barely press by hand until the drive side engaged. Then I used a rubber mallet and gently tapped the rest of the sleeve into place supporting the frame NDS. The sleeve NDS surface appears to be rather rough in the pic but its is just because of test fitting.

    Everything went smoothly and I personally think this fit is secure enough. Now I can always tap it out again should the need arise. If it starts to click or clack I'll just pull it apart and apply some Loctite.

    The length of the sleeve is perfect. There's a tiny gap on the NDS, just enough to make sure there's no pressure applied to the carbon shell. If you remove the bottom cable guide and look inside the frame you'll see there's absolutely nothing in there to take up axial forces except the thin carbon shell which is glued into the even thinner tubing walls. That was also part of my worries using this surface to support the washer when pressing. Besides any opportunity for lateral movement of the sleeve will be gone as soon as some dust and grit has gathered in between there.

    I think C-Bear came up with an excellent solution on how to fit Campy cranks but IMO they need to consider changing the tolerances for the fit.

    The new Record groupset will arrive at my doorstep tomorrow. I have a feeling this will be a great weekend.
    Attached Thumbnails Attached Thumbnails C-Bear OSBB >> Campy Adapter Install-dscn2470.jpg   C-Bear OSBB >> Campy Adapter Install-dscn2469.jpg   C-Bear OSBB >> Campy Adapter Install-dscn2473.jpg   C-Bear OSBB >> Campy Adapter Install-dscn2478.jpg   C-Bear OSBB >> Campy Adapter Install-dscn2483.jpg  

    Black bikes are nice, but red ones are faster.

  19. #19
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    Fit of C-Bear OSBB Sleeve

    Hello Steffo

    And I think you should "gently tap out" your sanded down sleeve - throw it away, and order a new one - this time around you should the install it as it has been explained several times on this forum!!

    What you have done to the sleeve makes it kind of useless!!

    The fit of 0.1mm is exactly correct, and should not be fiddled with!

    I have installed several of these sleeves now, without any issues at all - to remove them you just reverse the install.

    DO NOT USE LOCTITE WHEN INSTALLING THE SLEEVE - install it as it has been explained previously on this forum - period!!

    Please remember that several endusers look at this forum for real advice - not something somebody thinks out - these products have been tested rigorously before they where launched to the market!!

    With respect

    Mads

  20. #20
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    Steffo,
    I think I know what you are going to do. Not listen to Mads...lol.
    I know you have a mechanical background so will make an appeal to you. That sleeve the way you have it will be rock solid for the simple reason the lateral compressive force on the loose left hand flange will draw the sleeve through the BB and tight against the right hand flange inside wall.. Once the left hand side Campy threaded cup is installed...in addition to the very light press you have, that sleeve will be rock solid.
    I hope you try it and prove Mads wrong...what I would do.
    Cheers.

  21. #21
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    Agree ^ Maybe go ahead and bond it in?
    Last edited by RubeLogic; 08-08-2012 at 08:05 PM.

  22. #22
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    First of all let me say I posted this to show other members what I did, not to tell them what they should do. It is up to each and every one to draw their own conclusions but if this has confused any potential sleeve buyers Iím sorry. Based on my personal experience working as a mechanical engineer I think the fit is too tight the way itís delivered. Of course you can press things with 0.1mm tolerance but for this diameter letís just say itís a lot and carbon fiber isnít a very ductile material. The sleeve is only supposed to hold the cups with support from the BB shell, not transfer any twisting forces.

    Iíve had a conversation with Aria and Bart at C-Bear about my concern and they said the sleeve had to be designed to fit the majority of cases. They also said it is a rather tight fit and to be prepared, physically and mentally. Well I guess I failed on the mental part.

    Mads, I appreciate your comments but when you say the fit of 0.1mm is exactly correct it is according to what? If this sleeve has been tested rigorously before being launched to the market, where are the references?

    I consider myself being an end-user like the majority on this forum and I do not adopt every suggestion, modification or whatever written here but I think its interesting to read how things can be solved with different approaches. This is not the first time a finished product has been modified by a forum member. After all this is part of why we are here, to discuss technical solutions and different alternatives. Opinions may diverge, thatís just the way it is.

    Hopefully I will receive all the parts I need to assemble the bike this weekend and take her for a test ride. Yes itís a She, just look at the head tube. I think Iím gonna name her Marilyn LOL.
    Black bikes are nice, but red ones are faster.

  23. #23
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    You are spot on Steffo and completely agree and our backgrounds teach us that.
    As stated, I give credit to C-bear for its sleeve design but believe the press to be much too high. Yes, C-bear must design the sleeve to be worse case in sizing...safeguard against worse case tolerance stack up of small sleeve dia. in production + big OSBB bore dia. but the latter is held to a very tight tolerance and no doubt C-bear can hold sleeve dia. to +/- .0005". A guess is C-bear used the delrin bushing OD as a nominal when sizing the sleeve. This is wrong as the compessive strength between the delrin bushings and metal sleeve aren't even close and the lateral press will go up exponentially for the same size sleeve as Sablotny discovered and you wanted to prevent. I would have done the same as yourself. Further C-bear doesn't know the long term consequences of pressing a metal sleeve into a high modulus carbon shell with .004" of press. I am sure you don't want to find out and neither would I. This as you stated isn't even done with metal to metal bushing in bores.

    Further the lateral retention of the C-bear sleeve is far superior to plastic cups pressed into a carbon BB which the carbon OSBB was designed for...and really what makes the C-bear design so effective. The metal sleeve doesn't need a high level of interference as with plastic bushings which don't have lateral retention other than the axial preload of the crank. My personal belief is the sleeve could even be designed nominally 'line-to-line' with sleeve OD and ID of carbon bore the 'same' for a slip fit and the lateral retention of left hand cup torqued per spec to 25.8 ft-lbs would hold the sleeve in place rock solid.

    I look forward to your build with Record. Pretty exciting to build such a nice bike and I look forward to your pictures and riding impressions. Let me know if you have any cabling issues with Record as I have been there and done that. You can expect fantastic shifting performance with Campy and your bike with hidden cable routing..mine shifts flawlessly.
    Cheers.
    PS: a tip for best rear derailleur shifting is...a generous cable loop in back and I did not use an in line cable adjuster for the rear deraileur...only for the front derailleur. You can easily adjust rear cable tension at the rear derailleur but best to maintain an in line adjuster to tune the trim for the front derailleur.
    Last edited by roadworthy; 08-09-2012 at 04:43 AM.

  24. #24
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    Quote Originally Posted by RubeLogic View Post
    Agree ^ Maybe go ahead and bond it in?
    Shouldn't be a need but a good fall back position in the event there is any creep which is not uncommon with metal on carbon interfaces. In fact the industry has morphed on this recently and many times spec'ed Loctite for carbon shells. C-bear isn't the first BSA shell to market. Sram has been making one for a while now. They spec Loctite 609 for their sleeve. Also many use Loctite on delrin bushings per usual OS carbon shell aka PF-30 installations...depending on tolerancing.
    So Steffo has a good fall back with Locitite but I like his thinking of trying it first without. The lateral retention of the left hand Campy thread on cup is so strong, that sleeve should not creak even if sized line-to-line with the carbon shell bore.

    A last comment is I would NEVER use a full strength Loctite for this application....but ONLY a servicable green Loctite in the event you want to get it apart.
    Cheers
    Last edited by roadworthy; 08-09-2012 at 08:13 AM.

  25. #25
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    I'm loving my C-Bear sleeve. The BB is so wonderfully stiff now, just like it should be.

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