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  1. #1
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    Calfee Eccentric Stuck

    So I loosened the two 5mm bolts on the eccentric and I could not move it at all using my fingers.
    Spoke with Calfee today and they said it might be a tight fit and that I should be able to move with the BB wrench once the BB is installed.
    I installed the BB and now using the BB wrench I can only move the eccentric about 1/8 inch using a lot of force. Only the side that I have the wrench on moves.
    It seems that everything on this frame including the seatposts and brake mounts have too tight of a tolerance. Not user friendly at all. I am not sure what to do now, maybe take the eccentric out of the frame (if I can get it out) and put some grease on it?

  2. #2
    Pants are for suckaz HandsomeRyan's Avatar
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    Is there a hole in the 'eccentric' part? If there is, stick a small allen wrench in that hole and rotate the cranks around until they push/pull the eccentric by hitting that allen wrench, then hold the crank there to keep it under tension while you tighten the pinch bolts.

    I'm not sure how clear my description was, but basically you can use the crank arm against an object stuck into that hole to gain leverage.

  3. #3
    PMK
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    We don't have a Calfee and likely never will, but that's ok.

    The idea of using grease on a metal component against a Carbon component can cause problems over time. Aluminum and carbon do not always play well together. If the grease or lube that is used is conductive, this can corrode the aluminum in place. In extreme cases as the aluminum corrodes, it may expand causing further troubles to the carbon.

    Without grease, the aluminum against carbon can have issues from sweat or moisture.

    While I don't like using silicone anywhere near composites, a silicone or similar based grease that is non conductive may be best for an application with no amount of movement, and hopefully never needs a repair.

    Just offering some ideas, maybe some of the Calfee owners know of a "special sauce" recommended by Calfee

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    I have some carbon paste that acts as a lubricant but also has tiny particles in it that reduces the amount of torque needed to keep carbon parts from slipping. Its used mainly on carbon seatposts, but Calfee told me to use it on aluminum posts as well. I am going to see if I can get the eccentric out of the frame today to access what is going on.

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    It looks like there is an aluminum sleeve in the frame that the eccentrics (one on each side) insert into.
    When I turn the eccentric with the BB wrench there a metal on metal scraping sound.
    If I could get it out I could sand it with some fine grit paper and grease it, but its so tight I can barely rotate it with the wrench
    I have no idea how to get it out. If I had some really long bolts I could screw them into the threaded side and push out against the other side.

  6. #6
    hors category TandemGeek's Avatar
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    For those who have never worked on a Calfee, they use a self-designed eccentric comprised of two CNC'd aluminum halves that are pulled towards each other and up against the eccentric shell by a pair of through-bolts.



    If you want to see a nearly life-size image of the actual eccentric halves & bolts, click on the photo strip below.



    Calfees built after March of 2009 (or there abouts) use a somewhat larger version of the eccentric mated with an aluminum sleeve that is bonded into the carbon eccentric shell; again, click on the photo strip below. As noted in Update #11 of our Calfee Journal, "[Calfee] implemented a design change to their frames to accommodate a larger diameter eccentric, larger bolts, and an aluminum sleeve bonded to the inside of the .25" larger eccentric shell opening. This change accomplished three things:

    • It provided a more solid interface between the eccentric halves and the eccentric shell to eliminate some customer issues with eccentric slippage;
    • It moved the fixing bolts further away from the bottom bracket so that they would not be obstructed by the external bearing cups used for cranks like the FSA MegaExo and Truvative GigaPipe models; and,
    • It allowed for the use of a Bushnell eccentric -- a preferred spec. for daVinci Design's tandems, remembering Calfee now produces carbon frames for daVinci as well."




    As you can tell from the second image in the photo strip above, we opted to use the Bushnell eccentric on our Calfee instead of Calfee's as they've proven to be problem free in over a decade of use 4 of the other tandems we've owned during that period of time. Why switch horses?

    So, now that everyone has some background on what we're talking about here, my guess is... and this is just a guess, you need to take your bottom bracket out, remove the two bolts and then use a large drift (a headset removal tool would work well for this) to carefully tap the halves out of the frame. Now, if you have any trepidation about how to do this without getting the eccentric halves wedged-in even tighter, call Calfee and ask for their guidance. Remember, I WON'T warranty your frame if you void Calfee's warranty by buggering up your eccentric.

    Once you have them out of the frame take a photo of the two halves and of the eccentric that clearly depicts the extent of any marring caused during your inititial installation and send them to Calfee so they can instruct you on how best to go about carefully removing any displace materials and/or advising if the eccentric halves need to be replaced. As for the aluminum sleeve, again, Calfee will be able to advise how to proceed with refinishing the sleeve such that you only remove any displaced material so that the sleeve will accept the two halves without binding. The tolerances on these parts are intentionally tight and don't lend themselves to being force in or out.
    Last edited by TandemGeek; 02-04-10 at 02:15 PM. Reason: Forgot link: http://www.thetandemlink.com/calfee_tandem_11.html

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    I was thinking of getting two bolts and putting them in between the two eccentrics and then turning a nut on each end to push them out.
    I will shim the bolt and nuts with a thin piece of wood or plastic to avoid scratching or damaging anything.
    I don't want to use anything that requires using a hammer or other striking tool.
    Also waiting to hear from Calfee, called several times this morning.
    The eccentric on my Santana is very loose when i loosen the allen screws that hold in place.
    I don't see a need to have it so tight.
    I am growing impatient with this.
    Last edited by jnbrown; 02-04-10 at 01:10 PM.

  8. #8
    hors category TandemGeek's Avatar
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    Quote Originally Posted by jnbrown View Post
    I don't see a need to have it so tight. I am growing impatient with this.
    Can't speak to why it may have become so abnormally tight; mine fit up just fine when my '08 frame was re-worked to add the new '09 aluminum spec' sleeve. But, by fitting up fine, installation simply required a light film of lubricant and hand fitting the eccentric halves as a test fit. If they were the least bit out of kilter, they would bind a but once they were bolted up it worked as designed.

    That said, it is not the best eccentric design by a long shot which is why I was anxious to get the frame re-worked from the even more finiky un-sleeved carbon shell with the smaller eccentric to the new standard so that I could use the Bushnell eccentric.

    Frankly, watching you work your way through this build and given your experience with Calfee's eccentric I would STRONGLY recommend you consider switching over to a Bushnell eccentric; it will be far easier to live with... on par with your Santana's grub-screw design once you become familiar with it's single bolt operation.
    Last edited by TandemGeek; 02-04-10 at 02:16 PM.

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    Got them out of the frame by turning with the BB wrench and pulling outwards at the same time.
    I just ordered the Bushnell.

  10. #10
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    Quote Originally Posted by HandsomeRyan View Post
    Is there a hole in the 'eccentric' part? If there is, stick a small allen wrench in that hole and rotate the cranks around until they push/pull the eccentric by hitting that allen wrench, then hold the crank there to keep it under tension while you tighten the pinch bolts.

    I'm not sure how clear my description was, but basically you can use the crank arm against an object stuck into that hole to gain leverage.
    +1 on that. My only change would be that you can use the crank as a lever against a rag-wrapped 5mm allen wrench in one of the eccentric bolts. Mine are very tight too, so tight that I was not able to pound them out. But when I turned them a few times that loosened them up and out they came. I have the older eccentric that TandemGeek references, I think it is an Al eccentric in a titanium shell. I see some oxidation around mine now, imagine it will be a struggle getting it out for winter maintenance drill ...

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    I have had no problems adjusting the eccentric on my 09 Calfee, seems to move freely with bolts loosened. Based on TG's input I have considered installing a Bushnell but have been stuck at the old if ain't broke don't fix it. TG how about getting me motivated with some more insight as to why the Bushnell would be a better option. Certainly you could make an argument that I won't realize it is "broke" until I am forced to make some type of adjustment at which time a replacement eccentric of any kind may not be readily available.

    At the risk of irritating some people I have to say I do not understand why you would spend Calfee type money for a frame and then not have a professional build up the bike. My main concerns with the tandem, particularly since I am putting a stoker at risk are safety and reliability. I don't think I can achieve those objective with the limited experience I have*.
    Living in the SF bay area does give me the luxury of picking any one of a number of competent mechanics within a 45 minute drive


    *worked in a bike shop as a kid and doing the light maintenance on the current fleet of 11 bikes

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    Quote Originally Posted by chichi View Post
    I have had no problems adjusting the eccentric on my 09 Calfee, seems to move freely with bolts loosened. Based on TG's input I have considered installing a Bushnell but have been stuck at the old if ain't broke don't fix it. TG how about getting me motivated with some more insight as to why the Bushnell would be a better option. Certainly you could make an argument that I won't realize it is "broke" until I am forced to make some type of adjustment at which time a replacement eccentric of any kind may not be readily available.

    At the risk of irritating some people I have to say I do not understand why you would spend Calfee type money for a frame and then not have a professional build up the bike. My main concerns with the tandem, particularly since I am putting a stoker at risk are safety and reliability. I don't think I can achieve those objective with the limited experience I have*.
    Living in the SF bay area does give me the luxury of picking any one of a number of competent mechanics within a 45 minute drive


    *worked in a bike shop as a kid and doing the light maintenance on the current fleet of 11 bikes
    I am not sure what you mean by professional. Somebody who works in a bike shop? How would I know they have any more experience or know how than I do? I started riding a bike at around 6. I started working on them at around 16. I built my first bike from scratch at 21. I am now 52 and have built numerous bikes from scratch. This is the first one were the parts don't fit on the frame.
    I also build my own wheels and have been doing so for 5 years. Reading what you wrote does irritate me. I feel my stoker is safer having me build the bike because I am finding all the problems that otherwise would be unknown to me. The Calfee eccentric is a poor design and on my frame the parts to do not fit. The eccentric is two separate pieces, left and right. When you loosen the bolts to adjust it and turn one side, the other side will not turn with it until the bolts twist far enough apply some torque. Then the two sides will be lined up and you will have to turn the the other side to line them up. There have also been reports of them slipping under high loads. I was told I might want to use loc-tite on the bolts. What else do you need to know?
    Last edited by jnbrown; 02-04-10 at 04:13 PM.

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    Quote Originally Posted by jnbrown View Post
    I am not sure what you mean by professional. Somebody who works in a bike shop? How would I know they have any more experience or know how than I do?
    You raise good questions, certainly my bike shop experience 35 years ago did not make me a professional let alone qualified to work on today's high end bikes. I think many home mechanics may be better qualified than than some local shops to wrench if for no other reason than the home mechanic may be more willing to take the time to read and understand directions with each new piece of equipment. As I said living in the bay area gives me plenty of options for what I believe to be professional mechanics. I would like to think that Calfee would be able to refer you to somebody that can "professionally" build up one of their frames.





    Quote Originally Posted by jnbrown View Post
    The eccentric is two separate pieces, left and right. When you loosen the bolts to adjust it and turn one side, the other side will not turn with it until the bolts twist far enough apply some torque.
    The adjustments I have done on my eccentric have been with the crankset installed, maybe the spindle eliminates the twist thereby allowing both sides of the eccentric to turn freely

    Quote Originally Posted by jnbrown View Post
    This is the first one were the parts don't fit on the frame.
    I do not belive yours is the first Calfee frame that parts did not fit on easily, I know my mechanic has had unique issues on the Calfee tandems he has built.


    Quote Originally Posted by jnbrown View Post
    Reading what you wrote does irritate me.
    I did say "at the risk of irratating people I did not understand"......, you have expalined why you feel your experience is sufficient to build a your tandem. No hard feelings.
    Last edited by chichi; 02-04-10 at 05:17 PM.

  14. #14
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    No offense taken.
    I was pretty upset today dealing with this and thus the maybe hostile response.
    I even wonder sometimes that this is more than I signed up for.
    But I see the finish approaching albeit in slow motion.

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    I also want to retract my statement about the loose allen bolts not allowing both sides of the eccentric to track.
    It seems they provide enough support to do this and the bottom bracket also locks the two sides together.
    I am still going with the Bushnell because I think it will be much easier to adjust.

  16. #16
    hors category TandemGeek's Avatar
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    Quote Originally Posted by mburchard View Post
    I think it is an Al eccentric in a titanium shell. I see some oxidation around mine now, imagine it will be a struggle getting it out for winter maintenance drill ...
    Hmmm, probably not. Up and until they enlarged the eccentric shell opening and fitted the aluminum sleeve the eccentric shell was simply a cylindrical void in the hand-laid front bottom bracket, hence the long-standing issue with eccentric slippage under loads: just not a lot of bite given that composites aren't all that hard. So, unless they did something special to your Calfee, there is no sleeve in there... just nicely finished composite material that may or may not have any top coating. Our frame was nude, and so was the interior of the eccentric. Anyway, that oxidation may well be galvanic corrosion if the anodizing has worn thin or through. If so, it might be a good idea to see what Calfee recommends as periodic maintenance to keep the corrosion at bay.

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    hors category TandemGeek's Avatar
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    Quote Originally Posted by jnbrown View Post
    The Calfee eccentric is a poor design and on my frame the parts to do not fit.
    I'm not sure I'd call it a poor design, it's just not one of the best.

    As for parts not fitting, the only thing I can say is, welcome to the world of hand-made, custom bikes. I've had five custom-made frames of my own from three builders over the years and each one has had it's own 'personality' in terms of how it went together. The same has been true of many other boutique customs that I've helped folks get sorted out. This was, after all, the motivation and purpose behind my Calfee Journal which shared in gory detail the things that made our Calfee as well as a few components a bit qwerky; expect the worst and hope for the best. Pretty much like having a custom home built or commissioning a piece of art.

    Chasing threads, facing bottom brackets and head tube, reaming seat posts and wearing out your calipers and gauges checking to make sure parts will fit, then carefully test fitting are all part of the game. When something doesn't thread or insert the way you think it should, STOP! I learned this the hard way with bottom brackets having cross threaded half a dozen over the years.

    Anyway, like I said, sharing some of those 'growing pains' that come with building up and sorting out a truly custom, one-off bike was the purpose of our Calfee Journal and, frankly, I suspect everyone who's built up or sorted out a Calfee tandem could probably add a chapter of their own. Such is the nature of the beast.

    So, all I can say is, be patient and enjoy the process. You'll have just as many if not more challenges ahead once you start riding the bike and working out all of the kinks, and there will be kinks.

  18. #18
    hors category TandemGeek's Avatar
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    Quote Originally Posted by chichi View Post
    ... if ain't broke don't fix it.
    Good policy when it comes to machines. Seriously, if you or anyone else has not had any problems with their Calfee eccentric then keep-on keepin' on.

    As I said, it's not a poor design and not everyone has problems with them. The newer version should be even less prone to problems because of the things I mentioned earlier regarding better 'bite', better compatibility with the newer oversized bottom bracket designs and more robust bolts. In fact, the Calfee eccentric is ideally suited for the newer bottom brackets given how they tend to work (compressing against the eccentric when torqued) compared to the older types of Square Taper, Octalink and ISIS BB's that tend to work against the Calfee eccentric (pushing outward from the center of the eccentric as they are torqued).

    The latter is what I encountered given my use of Phil Wood tapers and that's where the Bushnell begins to shine. Like most other eccentrics, the Bushnell is build around a solid core into which the eccentric is installed. So, unlike the Calfee eccentric that can only be removed from the frame after you've removed the bottom bracket, the Bushnell allows you to remove the eccentric and bottom bracket as a single unit by simply removing one of the crank arms:



    It also allows for the use of a closed eccentric shell and then fills the entire void as it's tightened to form a tight fit around nearly the entire circumference of the shell. Many of the other designs compromise the integrity of the shell by using a split shell with pinch bolts to squeeze the frame around the eccentric or grub screws that use asymmetric pressure to push the eccentric against the opposite sides of the shell while deforming the face of the shell with the two grub screws. Again, these other designs work just fine, but they do so using inelegant designs that simply make the Bushnell more attractive and functionally superior. There is no need to compromise the shell, it does not mar itself or the shell the way grub screws do, and it uses a single bolt to both tighten and release the eccentric in an always simple and predictable manner.

    Moreover, the most recent generation of the Bushnell eccentric (#4) was completely re-worked by Todd Shusterman of daVinci designs who improved movement, spec'd a larger bolt to make it more durable, removed all of the excess material to make it extremely lightweight and spec'd a hard anodized finish that, once again, made it more durable (and black!). Below is a photo of Version #3 on the left and Version #4 on the right.



    Unfortunately, Todd's contributions to the redesign are barely even a footnote on R&E's marketing materials. Cest la vie. Again, Dennis Bushnell truly did come up with a better and more elegant eccentric and it's gotten better and better with each update. And, before anyone gets excited about the weight, believe it or not the Version #4 Bushnell eccentric at 129 grams is only 13 grams heavier than the new, larger Calfee eccentric.

    But, as I said at the outset, your philosophy is sound: If it ain't broke, there's no need to fix it.

  19. #19
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    Quote Originally Posted by TandemGeek View Post
    Hmmm, probably not. Up and until they enlarged the eccentric shell opening and fitted the aluminum sleeve the eccentric shell was simply a cylindrical void in the hand-laid front bottom bracket, hence the long-standing issue with eccentric slippage under loads: just not a lot of bite given that composites aren't all that hard.
    You are right, no shell. Mine fits VERY tightly. Guess at some point will loosen up, though, and then it goes back for the same mod you had done. Rear section of our frame is back to Calfee now so I can mount the Gates timing belt and rings ...

  20. #20
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    I'm beginning to feel bad since mine just went together, real easy and I'm not a "bicycle mechanic."
    It doesn't get harder, you just go slower.

  21. #21
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    knock on wood we have not had any issues to our late 2008 build but if it does we will send it back to Calfee for the update. It has been a fantastic ride so far and we travel with it often so it gets taken apart frequently but it has not required much adjustment on the eccentric for a long time. As per Craig"s instructions to me I just roll the timing chain on. Calfee did the initial build on ours so maybe they fine tuned the eccentric.

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    Anyone can assemble a bike with the machining quality of the parts we buy. If it was machined wrong it wont fit. I'd say you have a tolerance problem that needs attention. It's not rocket science and I'm amazed at some of the things people bring there bikes in for. I do work at a bike shop.

  23. #23
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    Quote Originally Posted by TandemGeek View Post
    Good policy when it comes to machines. Seriously, if you or anyone else has not had any problems with their Calfee eccentric then keep-on keepin' on.

    As I said, it's not a poor design and not everyone has problems with them. The newer version should be even less prone to problems because of the things I mentioned earlier regarding better 'bite', better compatibility with the newer oversized bottom bracket designs and more robust bolts. In fact, the Calfee eccentric is ideally suited for the newer bottom brackets given how they tend to work (compressing against the eccentric when torqued) compared to the older types of Square Taper, Octalink and ISIS BB's that tend to work against the Calfee eccentric (pushing outward from the center of the eccentric as they are torqued).

    The latter is what I encountered given my use of Phil Wood tapers and that's where the Bushnell begins to shine. Like most other eccentrics, the Bushnell is build around a solid core into which the eccentric is installed. So, unlike the Calfee eccentric that can only be removed from the frame after you've removed the bottom bracket, the Bushnell allows you to remove the eccentric and bottom bracket as a single unit by simply removing one of the crank arms:

    It also allows for the use of a closed eccentric shell and then fills the entire void as it's tightened to form a tight fit around nearly the entire circumference of the shell.

    But, as I said at the outset, your philosophy is sound: If it ain't broke, there's no need to fix it.

    TG, that Bushnell is obviously a nice item, and has made our list of future items for our Co-Mo.

    I am curious though, many of the recommendations posted tend to point towards contacting the oem for a solution. In regards to installing an expansion type eccentric into a carbon bike, even though yours now has an insert, what was Calfees thoughts on possible disbonds occurring in the local area of the Bushnell wedge? The oem Calfee design utilizes a compression concept which is normally preferred in composite structures. Expansion designs, can cause issues with composites, just curious if they endorsed the Bushnell and will warranty any disbonds or related issues after not using the Calfee eccentric.

    Not a rant nor attack, rather a curiosity about how they viewed this. Myself, as a composites guy, have some guidelines we tend to try and adhere to, one of which is minimizing stresses to create other possible failures, typically delaminations and disbonds. Obviously the answer is I could call them myself, but we know that won't happen as it's not that important to me.

    PK
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    Some single bikes and a couple of KTM's
    And most important, someone special that enjoys them with me (except the KTM's)

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    hors category TandemGeek's Avatar
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    Quote Originally Posted by PMK View Post
    In regards to installing an expansion type eccentric into a carbon bike, even though yours now has an insert, what was Calfees thoughts on possible disbonds occurring in the local area of the Bushnell wedge?
    Did you miss this part of the earlier dialog?

    Calfees built after March of 2009 (or there abouts) use a somewhat larger version of the eccentric mated with an aluminum sleeve that is bonded into the carbon eccentric shell; again, click on the photo strip below. As noted in Update #11 of our Calfee Journal, "[Calfee] implemented a design change to their frames to accommodate a larger diameter eccentric, larger bolts, and an aluminum sleeve bonded to the inside of the .25" larger eccentric shell opening. This change accomplished three things:

    • It provided a more solid interface between the eccentric halves and the eccentric shell to eliminate some customer issues with eccentric slippage;
    • It moved the fixing bolts further away from the bottom bracket so that they would not be obstructed by the external bearing cups used for cranks like the FSA MegaExo and Truvative GigaPipe models; and,
    • It allowed for the use of a Bushnell eccentric -- a preferred spec. for daVinci Design's tandems, remembering Calfee now produces carbon frames for daVinci as well."
    So, in fact, the ability to retrofit our Calfee to accept the Bushnell eccentric was a Calfee solution. I believe my understanding is correct in that Calfee redesigned the eccentric in part so it would accommodate the Bushnell eccentric, based on feedback from daVinci Designs as well as to address some other fitment issues as noted in my journal entry's quote above and earlier in this thread.

    As for the tie-in with daVinci Designs (noting both Calfee & daVinci are first and foremost design firms), you may or may not recall that Greg Lemond ordered what I believe was his 3rd Calfee tandem a couple years back, but he wanted this one fitted with daVinci's ICS system. Thus, the first ICS Calfee was born and shortly thereafter daVinci began to offer daVinci-branded Calfee-made tandems. daVinci had been a long-time user of the Bushnell eccentric and, as noted above, even had a major hand in re-engineering the Version #4. The solution has proven to be a win-win for everyone as the OEM Calfee eccentric is now an improved design and Calfee owners can, if they so choose, use the Bushnell eccentric.

    My Calfee was the first (and the only one to my knowledge) one to be retrofit to the new design. In fact, the folks in the Calfee shop (the James Gang) decided to let Craig perform the surgery which involved drilling out the original eccentric opening in our frame to accommodate the new aluminum sleeve. In talking with Craig and James, the bonded-in eccentric sleeve more than compensated for the loss of material in terms of the strength of the bottom bracket area. There are no indications to date that suggest otherwise.

    As for being a source of disbonds, remember that the Bushnell is not a wedge-type eccentric. It uses two expanding lobes that, as previously mentioned, expand to allow the OML of the eccentric to match the IML of the eccentric shell / sleeve on the frames for which it was designed. The latter causes the holding power to be distributed around the circumference of the sleeve instead of just a few hot spots. While I'm sure there is some external loading against the carbon shell when the eccentric is tighten, those loads aren't all that high and pale in comparison to the asymmetric ones put into the bottom bracket area from a rider's pedal inputs. Moreover, and in this regard, think about how much surface area Calfee's OEM eccentric halves are concentrating all of that asymmetric energy on (especially before the aluminum sleeve was added) compared to how that energy would be distributed by the Bushnell installed in the aluminum sleeve.

    Just some food for thought.
    Last edited by TandemGeek; 02-06-10 at 08:35 AM.

  25. #25
    PMK
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    Sorry TG, I did not interpret your DaVinci / Bushnell reply to fully carryover to the Calfee, my bad.

    In regards to the Bushnell, I do agree it spreads the loads across a greater area than a wedge style eccentric, but still is an expanding type device.

    As I compared the expanding type to the clamping style Calfee designed, the obvious difference is that Calfee has the load compressing an aluminum insert and not the composites.

    No big deal on my end, just was asking.

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