Page 1 of 2 12 LastLast
Results 1 to 25 of 30
  1. #1
    RoadBikeReview Member
    Reputation:
    Join Date
    Aug 2017
    Posts
    6

    Bottom Bracket help

    I'm completely lost here, hopefully someone can help.

    Building a Chinese carbon frame for a friend, and I can't find a bottom bracket that will work. It currently has a BB30, which the OD is correct, but it wont accommodate the 24mm shimano crank shaft. I ordered a set of BB30 adapters and they make the total width too wide for to have enough crank shaft exposed to mount the left crank arm. The shell is 90mm with the plastic cups in place.

    Aside from using a SRAM crankset, what are my options? He's already bought a 6800 groupset.

  2. #2
    'brifter' is a lame word.
    Reputation: cxwrench's Avatar
    Join Date
    Nov 2004
    Posts
    11,875
    90mm is exactly how wide it should be. A normal english threaded frame is 68mm, the cups are 11mm each. 90mm. A Trek carbon road bike is...BB90...90mm. If your friends bike is 90mm w/ the adapters installed and you can't get the left arm on you're doing something wrong. I can't say what w/o seeing the bike.
    I work for some bike racers
    I've got some bikes, some guns,
    and a bunch of skateboards

  3. #3
    RoadBikeReview Member
    Reputation:
    Join Date
    Aug 2017
    Posts
    6
    Its 90mm before the adapter are installed. Sorry if I wasn't clear.

  4. #4
    Forever a Student
    Reputation: MMsRepBike's Avatar
    Join Date
    Mar 2014
    Posts
    4,738
    Quote Originally Posted by Wattup View Post
    The shell is 90mm with the plastic cups in place.
    Quote Originally Posted by Wattup View Post
    Its 90mm before the adapter are installed. Sorry if I wasn't clear.
    Still not clear.

    I'm going to throw out a guess here:

    Grab a rubber deadblow mallet.
    Hit the driveside crank arm/spider firm.
    Presto.
    Now you have enough room to install the left arm.
    Sometimes it takes a man's touch.
    use a torque wrench

  5. #5
    RoadBikeReview Member
    Reputation: bikerjulio's Avatar
    Join Date
    Jan 2010
    Posts
    7,352
    Quote Originally Posted by Wattup View Post
    Its 90mm before the adapter are installed. Sorry if I wasn't clear.
    it's not BB30 then, is it.

    BB30 = 42 mm x 68 mm.

    If you don't know what you have, how can we help?

    Suggest you try again with the description.
    We just don’t realize the most significant moments of our lives when they’re happening
    Back then I thought “well there'll be other days”
    I didn’t realize that was the only day
    https://www.youtube.com/watch?v=Y9yrupye7B0

    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.
    http://www.youtube.com/watch?v=GekiIMh4ZkM

  6. #6
    'brifter' is a lame word.
    Reputation: cxwrench's Avatar
    Join Date
    Nov 2004
    Posts
    11,875
    It's definitely not BB30...

    Chinese carbon you say?
    I work for some bike racers
    I've got some bikes, some guns,
    and a bunch of skateboards

  7. #7
    RoadBikeReview Member
    Reputation:
    Join Date
    Jun 2015
    Posts
    235
    Are you sure it's not BB86 or BB386Evo? It's not BB30 if the shell is remotely close to 90mm wide.

  8. #8
    RoadBikeReview Member
    Reputation: kiwisimon's Avatar
    Join Date
    Oct 2002
    Posts
    5,499
    a couple of pictures will help but if you can insert the long spindle into the BB from both sides of the adapter to check bearing clearances try the rubber mallet taps on the drive side crank to drive it through the non drive side bearing. If in the check you can't insert the spindle through the non drive side bearing you may have a SRAM GXP BB adapter which has 24mm bearings on the right and 22mm on the non-drive side. Pics please.

  9. #9
    RoadBikeReview Member
    Reputation:
    Join Date
    Jul 2016
    Posts
    76
    Quote Originally Posted by ceugene View Post
    Are you sure it's not BB86 or BB386Evo? It's not BB30 if the shell is remotely close to 90mm wide.
    Yeah, my guess would be BB86 as well. Quite common on Chinese frames.

    Sent from my Pixel using Tapatalk

  10. #10
    RoadBikeReview Member
    Reputation: Lombard's Avatar
    Join Date
    May 2014
    Posts
    5,499
    Quote Originally Posted by cxwrench View Post
    Chinese carbon you say?
    Does he have an organ donor card?
    “Statistics are like bikinis. What they reveal is suggestive, but what they conceal is vital.” -- Aaron Levenstein

    "Beware of geeks bearing formulas."
    -- Warren Buffett

    "Education is what you get when you read the fine print. Experience is what you get when you don't. -- Pete Seeger



  11. #11
    RoadBikeReview Member
    Reputation:
    Join Date
    Aug 2017
    Posts
    6
    Quote Originally Posted by aske View Post
    Yeah, my guess would be BB86 as well. Quite common on Chinese frames.

    Sent from my Pixel using Tapatalk
    Thanks, I'll give that a try.

  12. #12
    RoadBikeReview Member
    Reputation:
    Join Date
    Aug 2017
    Posts
    6
    Quote Originally Posted by bikerjulio View Post
    it's not BB30 then, is it.

    BB30 = 42 mm x 68 mm.

    If you don't know what you have, how can we help?

    Suggest you try again with the description.
    I'm asking the question because I don't know what size it is. I used a micrometer to find the measurements, which I've included in my original post, in an attempt to find a solution. I don't have any experience with these Chinese frames.

  13. #13
    RoadBikeReview Member
    Reputation:
    Join Date
    Aug 2017
    Posts
    6
    Quote Originally Posted by MMsRepBike View Post
    Still not clear.

    I'm going to throw out a guess here:

    Grab a rubber deadblow mallet.
    Hit the driveside crank arm/spider firm.
    Presto.
    Now you have enough room to install the left arm.
    Sometimes it takes a man's touch.
    You could beat on this thing all day long and it's not going to budge unless you smash the carbon. The right side crank arm and chainrings are snug against the frame and I still don't have enough spindle on the other side to mount the left crank arm with the adapters in place.

  14. #14
    RoadBikeReview Member
    Reputation: bikerjulio's Avatar
    Join Date
    Jan 2010
    Posts
    7,352
    Quote Originally Posted by Wattup View Post
    I'm asking the question because I don't know what size it is. I used a micrometer to find the measurements, which I've included in my original post, in an attempt to find a solution. I don't have any experience with these Chinese frames.
    Sorry but you continue to make no sense at all. Your original post said it was BB30. (should be 68 mm wide) with no measurements. Here it is again

    Building a Chinese carbon frame for a friend, and I can't find a bottom bracket that will work. It currently has a BB30, which the OD is correct, but it wont accommodate the 24mm shimano crank shaft. I ordered a set of BB30 adapters and they make the total width too wide for to have enough crank shaft exposed to mount the left crank arm. The shell is 90mm with the plastic cups in place.
    Later you said it was 90 mm wide without cups in place.

    One does not need a micrometer to tell the difference.

    You have not posted the diameter either.

    Just saying "chinese carbon" is also fairly meaningless.

    Why not just post the width and diameter of the BB shell? Are bearings installed?

    A picture would also help.
    We just don’t realize the most significant moments of our lives when they’re happening
    Back then I thought “well there'll be other days”
    I didn’t realize that was the only day
    https://www.youtube.com/watch?v=Y9yrupye7B0

    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.
    http://www.youtube.com/watch?v=GekiIMh4ZkM

  15. #15
    RoadBikeReview Member
    Reputation:
    Join Date
    Aug 2017
    Posts
    6
    Quote Originally Posted by bikerjulio View Post
    Sorry but you continue to make no sense at all. Your original post said it was BB30. (should be 68 mm wide) with no measurements. Here it is again




    Later you said it was 90 mm wide without cups in place.

    One does not need a micrometer to tell the difference.

    You have not posted the diameter either.

    Just saying "chinese carbon" is also fairly meaningless.

    Why not just post the width and diameter of the BB shell? Are bearings installed?

    A picture would also help.

    I didn't say I needed a mic to tell the difference. Yes, he installed BB30's (which is why I said it has BB30), which have an OD of 42mm. Being as you seem to be a self-proclaimed bike guru, I thought you would have this information. The only reason I even mentioned that it was Chinese is because it's not like I can go to a manufacturers website or customer service for help. If this doesn't make sense to you, how about to refrain from commenting? Ever consider that approach, opposed to being a smartass?

    The shell is 90mm. Diameter is 42mm. Crank spindle is 24mm. What can I put in there that will work? That's all I'm asking.

  16. #16
    RoadBikeReview Member
    Reputation: bikerjulio's Avatar
    Join Date
    Jan 2010
    Posts
    7,352
    Just a student of BB standards trying to help.

    I'm not aware of any standard that meets what you say you have there. BB386EVO is closest but that would have the BB30 bearings in cups pressed into a 46 mm dia shell. The adapters for Shimano look like this for that 386EVO Adapter for 24mm Spindle Cranks (Shimano, FSA, etc.)
    We just don’t realize the most significant moments of our lives when they’re happening
    Back then I thought “well there'll be other days”
    I didn’t realize that was the only day
    https://www.youtube.com/watch?v=Y9yrupye7B0

    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.
    http://www.youtube.com/watch?v=GekiIMh4ZkM

  17. #17
    RoadBikeReview Member
    Reputation: kiwisimon's Avatar
    Join Date
    Oct 2002
    Posts
    5,499
    Quote Originally Posted by Wattup View Post
    I'm asking the question because I don't know what size it is. I used a micrometer to find the measurements, which I've included in my original post, in an attempt to find a solution. I don't have any experience with these Chinese frames.
    OP, post some pics of your measurements and the BB area please. Do you have a camera? Honestly a picture is worth a thousand words and this thread is already way too confusing. You asked for help, we tried to but from the get go your description was confusing. What make is the make and model of the frame and adapter?

  18. #18
    RoadBikeReview Member
    Reputation:
    Join Date
    Apr 2012
    Posts
    282
    I assume the problem is attempting to use a BB386EVO adapter intended for 86 mm shell on this press-in bearing 90 mm shell. I have no experience, but just looking at things it seems like the adapters will add a couple mm width on each side.

    scott s.
    .

  19. #19
    'brifter' is a lame word.
    Reputation: cxwrench's Avatar
    Join Date
    Nov 2004
    Posts
    11,875
    Quote Originally Posted by Wattup View Post
    I didn't say I needed a mic to tell the difference. Yes, he installed BB30's (which is why I said it has BB30), which have an OD of 42mm. Being as you seem to be a self-proclaimed bike guru, I thought you would have this information. The only reason I even mentioned that it was Chinese is because it's not like I can go to a manufacturers website or customer service for help. If this doesn't make sense to you, how about to refrain from commenting? Ever consider that approach, opposed to being a smartass?

    The shell is 90mm. Diameter is 42mm. Crank spindle is 24mm. What can I put in there that will work? That's all I'm asking.
    HTFU. You've half-asked so many questions it's no wonder none of us can help you. If the frame's bb shell is indeed 90mm wide w/ a 42mm hole in it you're not going to be able to install a Shimano 24mm axle crank...as far as I know. And I know a lot about bikes.
    I work for some bike racers
    I've got some bikes, some guns,
    and a bunch of skateboards

  20. #20
    RoadBikeReview Member
    Reputation:
    Join Date
    Jul 2013
    Posts
    265
    Cannondale should be f'n boycotted until they go bankrupt for all of the trouble they caused by sparking these new BB standards - absolutely none of which have been shown to offer any benefit whatsoever over the tried and true English threaded BB that has served us flawlessly for decades.

  21. #21
    RoadBikeReview Member
    Reputation: kiwisimon's Avatar
    Join Date
    Oct 2002
    Posts
    5,499
    I've never bought a Cannondale, bought plenty of US made bikes but.

  22. #22
    RoadBikeReview Member
    Reputation: bikerjulio's Avatar
    Join Date
    Jan 2010
    Posts
    7,352
    Quote Originally Posted by scott967 View Post
    I assume the problem is attempting to use a BB386EVO adapter intended for 86 mm shell on this press-in bearing 90 mm shell. I have no experience, but just looking at things it seems like the adapters will add a couple mm width on each side.

    scott s.
    .
    don't think so.

    BB90 is 90.5 mm wide with 37 mm moulded in bearing seats, taking a 37 mm od x 24 mm id bearing. Trek standard designed specifically for Shimano cranks.

    OP has insisted that it's 90 mm wide with BB30 size bearings, and we have pointed out that there's no such thing. Assuming he's correct about bearings the closest would be 86.5 mm wide BB386evo. Hence my advice.
    We just don’t realize the most significant moments of our lives when they’re happening
    Back then I thought “well there'll be other days”
    I didn’t realize that was the only day
    https://www.youtube.com/watch?v=Y9yrupye7B0

    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.
    http://www.youtube.com/watch?v=GekiIMh4ZkM

  23. #23
    RoadBikeReview Member
    Reputation: bikerjulio's Avatar
    Join Date
    Jan 2010
    Posts
    7,352
    Quote Originally Posted by aske View Post
    Yeah, my guess would be BB86 as well. Quite common on Chinese frames.

    Sent from my Pixel using Tapatalk
    BB86 is designed for Shimano and would not require adapters. So why would OP have a problem?
    We just don’t realize the most significant moments of our lives when they’re happening
    Back then I thought “well there'll be other days”
    I didn’t realize that was the only day
    https://www.youtube.com/watch?v=Y9yrupye7B0

    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.
    http://www.youtube.com/watch?v=GekiIMh4ZkM

  24. #24
    RoadBikeReview Member
    Reputation:
    Join Date
    Jul 2016
    Posts
    76
    Quote Originally Posted by bikerjulio View Post
    BB86 is designed for Shimano and would not require adapters. So why would OP have a problem?
    I'm just guessing wildly. Would be nice with some pictures...

    Sent from my Pixel using Tapatalk

  25. #25
    RoadBikeReview Member
    Reputation:
    Join Date
    Apr 2014
    Posts
    129
    Quote Originally Posted by Waspinator View Post
    Cannondale should be f'n boycotted until they go bankrupt for all of the trouble they caused by sparking these new BB standards - absolutely none of which have been shown to offer any benefit whatsoever over the tried and true English threaded BB that has served us flawlessly for decades.
    What does Cannondale have anything to do with any of this?? Do you know how many different headset standards there are? People always want lighter, stiffer, faster bikes & the manufacturers complied. You cant't offer the public those things without breaking some eggs.

    Bigger bottom bracket shells = greater stiffness & allows larger tube shapes for aerodynamics. The same thing happened with the headtube area. All this stuff was going to happen regardless. But I do understand your intent if somewhat misguided.

Page 1 of 2 12 LastLast

Similar Threads

  1. Help needed - can't get crank off bottom bracket
    By CRM in forum Components, Wrenching
    Replies: 12
    Last Post: 12-14-2004, 10:47 AM
  2. Bottom Bracket situation, Please Help
    By Coppi1952 in forum Components, Wrenching
    Replies: 7
    Last Post: 10-06-2004, 09:47 AM
  3. Bottom Bracket Help
    By paramountz in forum Components, Wrenching
    Replies: 2
    Last Post: 07-12-2004, 05:01 PM
  4. Help with stuck bottom bracket
    By mfuchs in forum General Cycling Discussion
    Replies: 3
    Last Post: 05-19-2004, 04:30 PM
  5. Bottom Bracket Help
    By morkm in forum Components, Wrenching
    Replies: 3
    Last Post: 02-29-2004, 04:43 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •