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  1. #1
    Daniel the Dog
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    It may be time for a new bottom bracket standard

    Shimano and other drivetrain manufactures do what they can to improve the performance of the bottom bracket crankset interface; however, it is inherently flawed.

    I'm less than excited about the X design. The bearings outside the BB shell getting douched by water and widening the Q factor. Ugh! I can't fell a real world difference in stiffness in my XT outboard cranks over my old Octalink system. The wider Q factor doesn't bother me all that much.

    The Isis system sat inside the shell but the bearing were too small and fragile to last. The old square BB was durable but did flex a bit. The Octalink system is probably the most succesful thus far but fell out of favor for some uknown reason.

    It is time for different standard. Why not a bigger bottom bracket shell. Keep it at 73mm and 68mm but make the shell larger, so the bearings fit inside the shell where they are protected from the elements and keep the Q factor narrow.

    They can make the head tube bigger. Why not the bottom bracket shell?

    Your thoughts?

    Jaybo

  2. #2
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    Quote Originally Posted by Jaybo
    I'm less than excited about the X design. The bearings outside the BB shell getting douched by water and widening the Q factor.

    What the heck did you think happened to the bearings on regular BBs? There's no such thing as a "sealed bearing". At least this way they can be be cleaned and serviced relatively easily.

    I feel a HUGE difference in stiffness with the hollowtech 2 cranks. Definitely makes for a solid ride when the rest of your bike is built solidly. If you can't feel any stiffness increase with that huge axle, then you'd be just as well served with old sugino cranks on a square taper. Those UN72 BBs always lasted a long time for me anyway.

    We might need a new standard, but the hollowtech 2 system is a huge step forward. Octalink just didn't get as long a life, and it was a good system, but hollowtech 2 is better. I can take off my crankset (for cleaning) by loosening a couple pinch bolts, instead of having to get some sort of crank-remover that presses the cranks out.
    "It's only when you stand over it, you know, when you physically stand over the bike, that then you say 'hey, I don't have much stand over height', you know"-T. Ellsworth

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  3. #3
    Daniel the Dog
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    That is your opinion! I COMPLETELY disagree....

    Quote Originally Posted by Jayem
    What the heck did you think happened to the bearings on regular BBs? There's no such thing as a "sealed bearing". At least this way they can be be cleaned and serviced relatively easily.

    I feel a HUGE difference in stiffness with the hollowtech 2 cranks. Definitely makes for a solid ride when the rest of your bike is built solidly. If you can't feel any stiffness increase with that huge axle, then you'd be just as well served with old sugino cranks on a square taper. Those UN72 BBs always lasted a long time for me anyway.

    We might need a new standard, but the hollowtech 2 system is a huge step forward. Octalink just didn't get as long a life, and it was a good system, but hollowtech 2 is better. I can take off my crankset (for cleaning) by loosening a couple pinch bolts, instead of having to get some sort of crank-remover that presses the cranks out.
    However, you have a right to your opinion. The Octalink system was easy to take apart and had an outstanding reliability record with a lower Q factor. The stiffness factor is complete placebo effect. I have outboard bearings, XT and Ultegra, on both my road and mountain bike and cannot feel a difference over Octalink. I regret buying both now after riding 'em. Hollowtech system is a only being used because we need a new BB standard. The Hollowtech 2 system has had plenty of mechanical problems too. It is deeply flawed system.

    Jaybo

    PS by the way, the XT crank was self extracting. Simple! Oh, yes, you have to face the BB shell on many frames for the HT 2 system. How ridiculous is that!
    Last edited by Jaybo; 02-04-2006 at 09:01 PM.

  4. #4
    Ebo
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    I've continued to use square taper cranks. They work well enough for me and the bb's last longer than a lot of the ISIS crap out there. Oh yeah. No experience with the outboard bearing cranks. They too have had some problems, but the potential is good.

  5. #5
    Meh.
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    Quote Originally Posted by Jayem
    What the heck did you think happened to the bearings on regular BBs? There's no such thing as a "sealed bearing". At least this way they can be be cleaned and serviced relatively easily.

    I feel a HUGE difference in stiffness with the hollowtech 2 cranks. Definitely makes for a solid ride when the rest of your bike is built solidly. If you can't feel any stiffness increase with that huge axle, then you'd be just as well served with old sugino cranks on a square taper. Those UN72 BBs always lasted a long time for me anyway.

    We might need a new standard, but the hollowtech 2 system is a huge step forward. Octalink just didn't get as long a life, and it was a good system, but hollowtech 2 is better. I can take off my crankset (for cleaning) by loosening a couple pinch bolts, instead of having to get some sort of crank-remover that presses the cranks out.
    Self-extracting crank bolts. But removing and replacing the cranks too often wears out the interface between the crank and bottombracket splines.

  6. #6
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    Drainage

    The tubes drain thru the BB.Why? I use scotch over the head hole. and the seat tube will drain to the BB too. A proper fender should protect the crank and the front tranny. There is no such design.
    Isis is the lightest.They`re all the same except weight?
    Q seems irrivelent on a MTB? The inconsistant nuture of it.
    Weight is what I bet on this year with an Am. Classic BB{replacable bearing} and FSA carbon crank.
    Expensive and high maintanenance. custom fender and the scotch tape for sure.
    130gram over octilink.It was good but I did`nt want to buy another. For my $350,XTR?

  7. #7
    Gimme my MOJO!
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    Quote Originally Posted by consumerbydesign
    The tubes drain thru the BB.Why? I use scotch over the head hole. and the seat tube will drain to the BB too. A proper fender should protect the crank and the front tranny. There is no such design.
    Isis is the lightest.They`re all the same except weight?
    Q seems irrivelent on a MTB? The inconsistant nuture of it.
    Weight is what I bet on this year with an Am. Classic BB{replacable bearing} and FSA carbon crank.
    Expensive and high maintanenance. custom fender and the scotch tape for sure.
    130gram over octilink.It was good but I did`nt want to buy another. For my $350,XTR?
    This has got to be one of the most confusing posts I have ever read!

  8. #8
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    Quote Originally Posted by leleklegrunt
    This has got to be one of the most confusing posts I have ever read!
    Yeah, I have no idea what the point he's trying to make is.

  9. #9
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    I think I like my '00 lx hollowtech cranks and xt bb. I also think you're over thinking this. It's a bike not the space shuttle and the parts work amazingly well. Lastly I think that it's probably your riding style that needs the work, not the bb.

  10. #10
    Neg reppers r my biatches
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    my standard is a Phil Wood bottom bracket....bomb proof.

  11. #11
    Elitest thrill junkie
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    Quote Originally Posted by Jaybo
    It is deeply flawed system.

    Jaybo

    PS by the way, the XT crank was self extracting.
    How is it deeply flawed?

    And as mentioned above, not only does it require much more force to remove the octalink cranks, but it wears the interface everytime you remove and install em.
    "It's only when you stand over it, you know, when you physically stand over the bike, that then you say 'hey, I don't have much stand over height', you know"-T. Ellsworth

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  12. #12
    Daniel the Dog
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    That is a good point

    Quote Originally Posted by Jayem
    How is it deeply flawed?

    And as mentioned above, not only does it require much more force to remove the octalink cranks, but it wears the interface everytime you remove and install em.
    However, I had a pretty old Octalink XT 752 that never wore out the interface despite repeated removals and installs. I think I've written about why I think the external bottom bracket technology is flawed.

    All I'm saying is make the bottom bracket shell a half inch bigger. Give the shell a bit more room, so manufactures can use bigger bearings and subsequently have stronger bottom brackets. Easy.

    I understand internals bottom brackets are not completely sealed but doesn't it make more sense to you to have them inside? Are you denying that external bottom brackets have had less than stellar durability records? You understand that Q factors are widened as a result of external bottom brackets.

    Heck! Cannondale has used a different BB technology on their road bike frames.

    It is just a thought but I understand people are slow to adapt new technology. It is one of the reason that outdated technologies continue to exist on bikes.

    By the way, I"m not trying to be argumentative but just think a bit...outside the box.

    Jaybo

  13. #13
    Elitest thrill junkie
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    Quote Originally Posted by Jaybo
    Are you denying that external bottom brackets have had less than stellar durability records?

    Yes. By and large, I think they've had excellent durability records.
    "It's only when you stand over it, you know, when you physically stand over the bike, that then you say 'hey, I don't have much stand over height', you know"-T. Ellsworth

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  14. #14
    Daniel the Dog
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    Use the search function on this site

    Quote Originally Posted by Jayem
    Yes. By and large, I think they've had excellent durability records.
    I think you may find a different opinion.

    Jaybo

  15. #15
    ballbuster
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    Quote Originally Posted by Jayem
    Yes. By and large, I think they've had excellent durability records.
    I gotta second this. I ride with lots of folks with external bearing cranks, and nobody seems to be having problems. Add to that, I live in Northern California, and we ride all year round through crazy mud.

  16. #16
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    Mass Confusion

    So I cleaned my BB. whats up with all that dirt and water in there?
    It seems to be coming in thru the tubes man.
    I gotta new bb and want to stop the infiltration.
    Are you still confused?

  17. #17
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    Quote Originally Posted by Jaybo
    I think you may find a different opinion.

    Jaybo
    I monitor the formums pretty frequently. I don't see a lot of "problems" with the external bearings. I'm still waiting for you to tell me what the "flaw" is.
    "It's only when you stand over it, you know, when you physically stand over the bike, that then you say 'hey, I don't have much stand over height', you know"-T. Ellsworth

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  18. #18
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    Quote Originally Posted by consumerbydesign
    So I cleaned my BB. whats up with all that dirt and water in there?
    It seems to be coming in thru the tubes man.
    I gotta new bb and want to stop the infiltration.
    Are you still confused?
    Drill a hole in the bb shell to let it drain out. SpeedNate posted some excellent dirx on how to do this.

  19. #19
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    More Holes? No Thanks

    Quote Originally Posted by Shawn595
    Drill a hole in the bb shell to let it drain out. SpeedNate posted some excellent dirx on how to do this.
    If I went that route,I would glue on the cable thingy on the bottom of the shell and remove the bolt that currently holds the cable thingy on. Got that? Utilize the existing hole.
    But,a big but. I dont want holes. the water is trashing my BB bearings.
    The hollow tubes leading to the shell need to be sealed.
    The shell is not "sealed".
    Everyone says my Isis Am.Classic replaceable bearings will not last very long.
    Ok, so the bike needs to drain. But thru my bearings?
    I`ll be covering up the holes of unused water cages, Under the fork the big hole gets scotch tape. To keep out water and the 100s of grams of dirt .
    The seatpost on mt HT has a hole thats perfectly in line to collect water and send it directly to the BB.
    People look at me funny for scotch taping over my hollow cranks.
    I want a fender that protects the direct assult on the drive train. For a lot of funny looks.
    Who cares ? I do long endurance rides away from the "park" anyways.

  20. #20
    Daniel the Dog
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    Use the search function

    Quote Originally Posted by Jayem
    I monitor the formums pretty frequently. I don't see a lot of "problems" with the external bearings. I'm still waiting for you to tell me what the "flaw" is.
    1) I don't like the wider Q factor. Too wide
    2) Problems with bearings blowing up (use the search function). LBS also said they have seen this in many bikes

    Use your mind and try and lose your typical argumentative approach. Think about it! How much sense does it make to have the bearings outside the BB shell. None!

  21. #21
    Formerly DMR For Life
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    the problem that i see with a new standard is that sales of the new bb's will be not be high enough to offset the R&D costs...ie you have to get a new bike to upgrade and can't just upgrade your existing bike (which we all like to do)
    DMR

  22. #22
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    consumerbydesign - quit using tape and get a front fender.

    I have 3 bikes that use sqare taper. Two of them is the sealed kind and the other one can be serviced. I've never had a problem with any of the bikes. Keep in mind every one of these bikes has seen ugly nasty conditions and lots of water and mud yet the square tapers hold up fine.

    IMHO Hollowtech 2 was just another Shimano "Lets create a product to fix a problem that dosen't exist" much like Dual Control.
    My Bike: '15 Trek FX 7.2
    My Blog: http://http://kona0197.wordpress.com/

  23. #23
    Elitest thrill junkie
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    Quote Originally Posted by Jaybo
    1) I don't like the wider Q factor. Too wide
    2) Problems with bearings blowing up (use the search function). LBS also said they have seen this in many bikes

    Use your mind and try and lose your typical argumentative approach. Think about it! How much sense does it make to have the bearings outside the BB shell. None!
    And you still havent told me what the "flaw" is.

    A flaw is an improperly designed part, or void in metal/casting. This is what might cause something to fail, but when you just say that the bearings have "problems", it's vague and is not pointing out an actual "flaw".

    I don't see many people having problems with the bearings. I see lots of people complaining about certain products from time to time, but I also know that for particular products there are just lots of them out there on peoples bikes, and a few stories doesn't mean it's a bad product or has a "flaw". Original XTR hollowtech 2 cranks had some intial bearing problems, but that was a while ago and doesn't apply today. XT, LX, and XTR bearings are solid.
    Last edited by Jayem; 02-05-2006 at 07:31 PM.
    "It's only when you stand over it, you know, when you physically stand over the bike, that then you say 'hey, I don't have much stand over height', you know"-T. Ellsworth

    You're turning black metallic.

  24. #24
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    Quote Originally Posted by Kona0197
    consumerbydesign - quit using tape and get a front fender.
    Or a rear fender.. whatever. Still a funny post!

  25. #25
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    I have to agree with Jayem that the accusation of flaws sounds vague. I never got more than a year out of my octalink EN72 BB but I have a year and a half on my XT External bearings with no major issues yet. I would hardly say I can feel a stiffness issue at all but the only complaint I have about the external bearings is chainline. Q factor is a non issue for me.

    All of that said the arguement for maintenance is a valid one for me as well even though I have all the tools. I much prefer to work on an external bearing system.

  26. #26
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    Quote Originally Posted by Jaybo
    Shimano and other drivetrain manufactures do what they can to improve the performance of the bottom bracket crankset interface; however, it is inherently flawed.

    I'm less than excited about the X design. The bearings outside the BB shell getting douched by water and widening the Q factor. Ugh! I can't fell a real world difference in stiffness in my XT outboard cranks over my old Octalink system. The wider Q factor doesn't bother me all that much.

    The Isis system sat inside the shell but the bearing were too small and fragile to last. The old square BB was durable but did flex a bit. The Octalink system is probably the most succesful thus far but fell out of favor for some uknown reason.

    It is time for different standard. Why not a bigger bottom bracket shell. Keep it at 73mm and 68mm but make the shell larger, so the bearings fit inside the shell where they are protected from the elements and keep the Q factor narrow.

    They can make the head tube bigger. Why not the bottom bracket shell?

    Your thoughts?

    Jaybo
    This already exists: http://www.fullspeedahead.com/fly.as...xid=60&pid=249

    The frame manufacturers just need to start making frame for them! This new BB has an M48 thread, which measures about 1.9", as opposed to the current standard which is about 1.37". This should allow much bigger ang stronger ball bearings for better reliability.

    BTW: I also still use square taper on most of my bikes. I am in the process of trying to find a cheap ISIS BB to replace the one that is toast on my Palomino after like 500 miles!

    Mark

  27. #27
    Mantis, Paramount, Campy
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    All BB Shells Should Be Faced

    Quote Originally Posted by Jaybo
    PS by the way, the XT crank was self extracting. Simple! Oh, yes, you have to face the BB shell on many frames for the HT 2 system. How ridiculous is that!
    This is not just something for external bearing BB's. A Shimano UN-5x, 7x, 9x BB should have the BB faced, and old school cup and cone BB should have the shell faced. Octalink BB's should have the shell faced. Any bottom bracket that has any interface with the face of the BB shell requires a well faced shell. Some frame manufactures do this at the factory, some do not. Same goes with the headtube.
    Phil Wood and early 90's Campagnolo cartridge BB's are the only ones I can think of off the top of my head that would not require facing of the BB shell prior to install.
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  28. #28
    Cut Casing Whisperer
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    Quote Originally Posted by bikeny
    This already exists: http://www.fullspeedahead.com/fly.as...xid=60&pid=249

    The frame manufacturers just need to start making frame for them! This new BB has an M48 thread, which measures about 1.9", as opposed to the current standard which is about 1.37". This should allow much bigger ang stronger ball bearings for better reliability.
    Mark
    Exactly. The problem with outboard bearing design is that it is a hack to get to bigger and more bearings while having a large and stiff spindle. It is a hack because the best design would have the bearings in the the BB shell. But the shell diameter is not big enough so the bearings had to be placed outside the shell.

    The ideal design would have the larger bearings inside the BB shell.

    So while the outboard bearings seem to work pretty well, a larger diameter BB shell should be a better solution. See BMX standards. BMX bikes are singlespeeds and jumpers and hold up well.

    Mr. P

  29. #29
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    Quote Originally Posted by bikeny
    I am in the process of trying to find a cheap ISIS BB to replace the one that is toast on my Palomino after like 500 miles!

    Mark
    $13!

    http://www.jensonusa.com/store/produ...hlt+Bb+Oe.aspx

    Mr. P

  30. #30
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    Quote Originally Posted by Mr.P
    Thanks, but unfortunately I need a 118 spindle for an E-type.

  31. #31
    The devil is an angel too
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    Quote Originally Posted by Kona0197
    consumerbydesign - quit using tape and get a front fender.

    I have 3 bikes that use sqare taper. Two of them is the sealed kind and the other one can be serviced. I've never had a problem with any of the bikes. Keep in mind every one of these bikes has seen ugly nasty conditions and lots of water and mud yet the square tapers hold up fine.

    IMHO Hollowtech 2 was just another Shimano "Lets create a product to fix a problem that dosen't exist" much like Dual Control.
    No, it wasn't. Shimano's Octalink was an attempt to improve BB performance, by creating a stiffer interface. Some may argue about the necesity of an stiffer interface -although this need seems quite obvious for the freeride crowd- but, even from an "improvement" point of view, it is not bad. Just like threaded headsets worked just fine, threadless were an improvement. However, Shimano's marketing stupidity caused the creation of ISIS. ISIS made apparent the short commings of an increased BB spindle. For what is worth, Octalink BB's were far more durable than ISIS, a fine product indeed.

    So, Shimano copied the Bullseye concept and produced HollotechII, this time they were smart and allowed for an open standard, and they created a good product. Like everyting, it comes with a price. The main issue is the Q factor and chainline, but, as an owner of an external bearing crank, I can say that it is worth it.

    And Dual Control was Shimano's attempt to translate to mountainbiking a concept that has proven very succesful in road bikes. You may not like it, but some people do. Is like gripshift, I don't like gripshifters, others do.

  32. #32
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    It is past time for a new BB standard. ISIS is crap because the bearings are too small. External is crap because the bearing seals are insufficient. Both problems are magnified by hardcore freeriding in a wet gritty climate.

    Why not increase the diameter of the BB shell to use some readily-available, cheap, strong, replaceable cartridge bearings with good seals? (like the ones in hubs, frame pivots, headsets)

  33. #33
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    Pinarello M.O.S.T. BB

    Has been around for a while.

    They know a thing or two about building bikes.

  34. #34
    Daniel the Dog
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    Nonsense

    Quote Originally Posted by Shayne
    This is not just something for external bearing BB's. A Shimano UN-5x, 7x, 9x BB should have the BB faced, and old school cup and cone BB should have the shell faced. Octalink BB's should have the shell faced. Any bottom bracket that has any interface with the face of the BB shell requires a well faced shell. Some frame manufactures do this at the factory, some do not. Same goes with the headtube.
    Phil Wood and early 90's Campagnolo cartridge BB's are the only ones I can think of off the top of my head that would not require facing of the BB shell prior to install.
    I give you on you people! If the bike industry lived in your worlds, we would still be riding the old cruisers. I have never had a bike BB shell faced. Ever. An Octalink shell doesn't need facing. Why?

    Jaybo

  35. #35
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    what dictionary are you reading?

    Quote Originally Posted by Jayem
    And you still havent told me what the "flaw" is.

    A flaw is an improperly designed part, or void in metal/casting. This is what might cause something to fail, but when you just say that the bearings have "problems", it's vague and is not pointing out an actual "flaw".

    I don't see many people having problems with the bearings. I see lots of people complaining about certain products from time to time, but I also know that for particular products there are just lots of them out there on peoples bikes, and a few stories doesn't mean it's a bad product or has a "flaw". Original XTR hollowtech 2 cranks had some intial bearing problems, but that was a while ago and doesn't apply today. XT, LX, and XTR bearings are solid.
    We would still be in England if it were guys like you. No vision! Are you an accountant by chance?

    Jaybo

  36. #36
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    Quote Originally Posted by Jaybo
    We would still be in England if it were guys like you. No vision! Are you an accountant by chance?

    Jaybo
    Well, I'd just say that you're fighting change just to try and stand up for something, not really caring whether or not it's valid.
    "It's only when you stand over it, you know, when you physically stand over the bike, that then you say 'hey, I don't have much stand over height', you know"-T. Ellsworth

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  37. #37
    Daniel the Dog
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    Wink Solid argument there....

    Quote Originally Posted by Jayem
    Well, I'd just say that you're fighting change just to try and stand up for something, not really caring whether or not it's valid.
    How can I debate that argument? Laughing. Sure, it makes sense to put the bearings outside the BB shell because the shell itself is too small to allow for a decent size bearing set to fit into. Sounds logical to me! Widen the Q factor....with many reports of failure. All makes perfect sense

    Jaybo

  38. #38
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    Technically It Does

    Just because you choose not to do it doesn't mean it shouldn't be done.
    Any bottom bracket that has parts (ie lockrings or cups) that touch the face of the bottom bracket shell require the frame to be faced.
    It is true that you don't NEED to face any bottom bracket shell it is just a recommended step. If the faces are not parallel to each other and perpindicular to the threads no BB (as described above) will install 100% correctly. Either the cups or lockring wont seat totally and will eventually loosen or the cup can twist slightly or deform which can lead to preloading the bearings or bending the spindle.
    A Shimano square taper cartridge or an Octalink BB won't work any better on a poorly prepped frame than an external BB will.
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  39. #39
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    Quote Originally Posted by Jaybo
    ....with many reports of failure. . . .

    Jaybo
    The proof is in the pudding. Got any pudding to share? I've got way more mileage on external well sealed bearings than I ever got on any internal BB. Seems like generalizations to prove your point without specifics.

  40. #40
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    For those that doubt the flawed design of the ISIS system, just go to the product reviews section for Bottom Brackets. Almost every ISIS BB listed has a score less than 3.0, with many below 2.5. The Shimano ones seem a little better, but the listings for them are confusing, so it is hard to tell. Also, and I find this interesting, one of the companies that helped develop the ISIS standard never produced a Bottom Bracket because they figured out that the bearings just could not be made durable enough to put their name on: Chris King.

    The new outboard bearing designs may work better, but it is still a Rube Goldberg to get around the fact that the current BB shell standard is too small for the spindle sizes they want to use. And it creates other problems like Q-factor, chainline and sealing, which may or may not be a problem in certain applications. I do like the spindle/crank interface though.

    They really should just make the shell bigger and use bigger internal bearings and the new crank interface. I think that would be the ideal solution. Also, the bigger BB shell would make for a stronger frame in the BB area because you have more meat to weld to. Until that time, I will be sticking with the old reliable, square taper, for most of my bikes.

  41. #41
    Daniel the Dog
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    Quote Originally Posted by Asahi
    The proof is in the pudding. Got any pudding to share? I've got way more mileage on external well sealed bearings than I ever got on any internal BB. Seems like generalizations to prove your point without specifics.
    Go here:

    http://www.peterverdonedesigns.com/b...ombrackets.htm

    The bearings last longer if you pull 'em apart and put decent grease in them. Not much room for grease though due to a marginal design.

    Jaybo

  42. #42
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    I'm not sure what I am looking for at that link. I was looking for perosnal individual testimoy of failures in the last year or 2. I've not seen very many complaints of the bearing design despite the claims that there is a problem. Are there links on MTBR of those discussing there issues? Seems like if it was a big problem (like ISIS) then there would be lots of threads about it (Like ISIS).

  43. #43
    Daniel the Dog
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    I was probably hard on the old outboard bearing cankset

    The bearings near the pedals certainly adds to the stiffness of the crankset. I just can't feel it. None of you agree with my call for a new standard. Oh, well, I guess that is why I ain't an engineer.

    Jaybo

  44. #44
    Cut Casing Whisperer
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    Quote Originally Posted by Jaybo
    None of you agree with my call for a new standard. Oh, well, I guess that is why I ain't an engineer.

    Jaybo
    There are about half a dozen posts in this thread saying a bigger BB shell should be better than the current standard.

    Mr. P

  45. #45
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    Perfect lets have a new BB standard!!! I can't wait!!! Just think that will give all the frame building companies a chance to adjust to the new standard. They would have to recalculate chain lines, chain stay lengths, and geometry issues. Forcing new hub standards. It will force little companies like Evil, Gammut, BlackSpire and others to have to redesign the chain guide and ISCG. Then that would have to force all the BB and Crank manufactures to have to comply and redesign. Then forcing a new tool standard. Forcing everybody to new standards that may inherantly be flawed.

    All the while in the name of customer convienece they force a price mark up. All for the few who could not do their regular maintainance. All for the lazy few who would not take a few minutes to clean up the bike after a ride. All for the few who did not want to learn to regularly check ups the bike.

    Oh well.... lets do it. It would make for some exciting new trade shows....Interbike 2008 here it comes!!!! Lets do it to support the corperate giants (Shimano) who can force and impose new standards at the expense of the little guys and customers. Lets do it... since they can easily retool their factories in no time, where as the little guys have a harder time keeping up with all the new implemented standards. We all know how much we love those guys. I think that I want to send them a Valentines card.
    Bikeless Rider

  46. #46
    Daniel the Dog
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    That is true

    Quote Originally Posted by Mr.P
    There are about half a dozen posts in this thread saying a bigger BB shell should be better than the current standard.

    Mr. P
    I was just trying to get people thinking and giving their opinions. When you do so, some people get all pissy because they are married to certain products and technologies. Maybe the outboard bearing systems works. Maybe? I still think there may be a better way. I just think bike companies are slow to adapt new technologies. Well, except for Cannondale.

    Jaybo

  47. #47
    Elitest thrill junkie
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    Quote Originally Posted by Jaybo
    The bearings near the pedals certainly adds to the stiffness of the crankset. I just can't feel it. None of you agree with my call for a new standard. Oh, well, I guess that is why I ain't an engineer.

    Jaybo
    Maybe not in in the way you think; I think the guy above summed it up pretty well. If you change the standard, there's so much other stuff that has to change. If you're (not pointing out anyone specifically) the type of person that complains about new standards and having to "upgrade" to new equipment, this will be a worst-case senario for you, as there are so many other things that have to change. Outboard bearings do make the best of the situation, and I would agree it's not a perfect solution, but too much other stuff would have to change if we changed the BB standard, and it would be a never-ending soure of headaches and new standards IMO.
    "It's only when you stand over it, you know, when you physically stand over the bike, that then you say 'hey, I don't have much stand over height', you know"-T. Ellsworth

    You're turning black metallic.

  48. #48
    Cut Casing Whisperer
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    Quote Originally Posted by wyrm
    Perfect lets have a new BB standard!!! I can't wait!!! Just think that will give all the frame building companies a chance to adjust to the new standard. They would have to recalculate chain lines, chain stay lengths, and geometry issues. Forcing new hub standards. It will force little companies like Evil, Gammut, BlackSpire and others to have to redesign the chain guide and ISCG. Then that would have to force all the BB and Crank manufactures to have to comply and redesign. Then forcing a new tool standard. Forcing everybody to new standards that may inherantly be flawed.
    Good point. I didn't think about the implications down to the tools. BUT... Outboard bearing is a new BB standard. Which means calculating new chain lines, and tools.

    Eccentric bottom brackets seem to be doing alright. No one is complaining about the bigger shell and "recalculate chain lines, chain stay lengths, and geometry issues"

    BMX bikes seems to be fine with the larger standard. No complaining there.

    And since when are bikes about sicking with a standard just because is was a standard established 15-20 years ago. The reason why we pay big bucks for bikes is for the latest engineering. You can buy an old standards bike, they are at Walmart.

    Every few years a frame designer will try a new linkage system, and that will "recalculate chain lines, chain stay lengths, and geometry issues" as well as new tooling and education.

    Another example is head tube sizing. Should we have stayed with 1"? Now there is 1.125" and 1.5" Not a lot of complaints I can see.

    I agree that there would be pain in the changing standards process but, I think saying never is impossible. The question is when and best implementation.

    Mr. P
    Last edited by Mr.P; 02-09-2006 at 10:35 AM.

  49. #49
    Cut Casing Whisperer
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    Quote Originally Posted by Jayem
    If you change the standard, there's so much other stuff that has to change.
    I curious about your thoughts about what I posted above about changing the standard, to sum up:

    "I think saying never is impossible. The question is when and best implementation."

    http://forums.mtbr.com/showthread.ph...84#post1565584

    Mr. P

  50. #50
    I ride a Swarf
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    another vote for a bigger shell standard.It will allow the bigger stiffer shorter axles. yeah the bearings are closer together, but so will the axle ends be too so the flexing leverage is canceled out to a degree. The bearings will probably be cheaper too. Most importnantly is the Q-Factor.

    External bearings work but are a bit of a fudge in my opinion. I'll prbably stick with my octalink setup even if it mean that the BB was the last bit of shimano on my bike (it and my xt cranks might be the lsat bits too if i get a rohloff speedhub). Roox make cranks for the octalink standard.....mmmm and they look lush too hehe.

    I'd even like a narrower q than holotech 1 xt cranks offer (getting shorter spindles for my eggy pedals to help).

    I wonder how many of the ppl worrying about a better BB standard ride with 1 1/8 headsets, suspension forks, rear suspension, non steel frames, 29 inch wheels, disk brakes...etc.

    Stu
    What exactly is a rigid hard tail?

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