MTBeer Posted June 19, 2018 Share Find me a 24376 then... And fit it for free You mean you charge for fitting bearings? How very dare you? Link to comment Share on other sites More sharing options...
Titanium Rocket Posted June 19, 2018 Share Can you get stuff from Rush Sports direct? I live close to Pmb and went there about 6 months ago, the guy said they no longer sell direct to the public ... Link to comment Share on other sites More sharing options...
PeterF Posted June 19, 2018 Share Can you get stuff from Rush Sports direct? I live close to Pmb and went there about 6 months ago, the guy said they no longer sell direct to the public ...Correct they don't but your lbs can order from them. Link to comment Share on other sites More sharing options...
DieselnDust Posted June 19, 2018 Share https://tokencycling.co.za/shop/token-pf30-thread-fit-bb-bb30-crank/ This is the one that will work properly, as per all the recommendations above. Does the token and WM PF30 threaded bb's have sufficiently tight tolerances and threaded length to cater for the extra 5mm length of a Cannondale Ai bb shell? Answer : no need to purchase the press together version Edited June 19, 2018 by DieselnDust Link to comment Share on other sites More sharing options...
Spoke101 Posted June 19, 2018 Share Find me a 24376 then... And fit it for free ABEC-3, ABEC-5, MAX?K,S,R,L,W?2RS, RS, 2Z, Z, E? :ph34r: Link to comment Share on other sites More sharing options...
RocknRolla Posted June 19, 2020 Share Please talk to me about BB in a yeti carbon frame. The wifes bike's cranks had some real difficulty spinning freely. Took the crank arms out to check the bearings. The onebearing is turning, but it feels real rough. The other bearing (non drive side) is seized up solid. Now upon inspection, what I can only assume to be cups in the carbon frame seems to be damaged on the inside ( I will take some pics and post) My questions, 1) are the cups pressed into the carbon shell? 1.1)Are the cups removable? 1.1.1) How many body parts do these cups cost? 2) Can the bearings be removed without removing the shells? 2.1) Does this require a special tool 2.1.1) How many body parts do these special tools cost? 2.1) if the shell is damaged, can this cause bearing interference, which will result in the bearing under performing? Edited June 19, 2020 by RocknRolla Link to comment Share on other sites More sharing options...
DieselnDust Posted June 19, 2020 Share If you can post pics then it's easier to answer your questions.I will say that frame alignment seems to be a massive problem in the bike industry. It's not uncommon for bb shell bearing races to be misaligned to each other and to the headset i. E. Many bikes are skew Link to comment Share on other sites More sharing options...
Eldron Posted June 19, 2020 Share The best PF BB replacement is a new bike with a T47 BB format. Faaark there are not enough words inside me to fully explain how much I hate the pressfit BB format and not enough swear words in the English to curse manufacturers for releasing that format to the world. Max Headroom, Wayne pudding Mol and Mojoman 3 Link to comment Share on other sites More sharing options...
DieselnDust Posted June 19, 2020 Share The best PF BB replacement is a new bike with a T47 BB format. Faaark there are not enough words inside me to fully explain how much I hate the pressfit BB format and not enough swear words in the English to curse manufacturers for releasing that format to the world.But why? Every other machine in the world uses press fit bearings...Successfully Edited June 19, 2020 by DieselnDust Link to comment Share on other sites More sharing options...
DuncanCT Posted June 19, 2020 Share If you want BB geek content... https://www.youtube.com/channel/UCH9263dSaOHFe25dkyGAu3Q Check out his bb's here... https://www.hambini.com/ Press fit seems to be technically the best solution but generally implemented poorly in the bicycles industry. Edited June 19, 2020 by DuncanCT DieselnDust 1 Link to comment Share on other sites More sharing options...
Eldron Posted June 19, 2020 Share But why? Every other machine in the world uses press fit bearings...Successfully Because mating plastic to other plastic then giving them both 90 offcentre cyclic loads a minute wears them out pretty quickly. Neither were designed to be wear surfaces. First they creak, then they creak more then eventually they're so lose they don't creak anymore. On the plus side you can then pop a new SF (slide fit) BB in with two fingers. Manufacturers love them because all they have to do is ream two badly off centre holes into a frame and call it done all the while telling us how much weight they saved us. DieselnDust and Prince Albert Cycles 2 Link to comment Share on other sites More sharing options...
DieselnDust Posted June 19, 2020 Share Because mating plastic to other plastic then giving them both 90 offcentre cyclic loads a minute wears them out pretty quickly. Neither were designed to be wear surfaces. First they creak, then they creak more then eventually they're so lose they don't creak anymore. On the plus side you can then pop a new SF (slide fit) BB in with two fingers. Manufacturers love them because all they have to do is ream two badly off centre holes into a frame and call it done all the while telling us how much weight they saved us. That's spot on! Its implemented poorly by many manufacturers. Problem with threads is the same *&^wits will tap threads off centre too! Threaded BB's were designed when BB's had loose balls and a cup and cone arrangement for the cups and axle. You could then preload the bearings properly.The Italian BB's had the threads cut through the BB from one side so the Threads were always aligned because the thread tapas still engaged while the other side was being cut. One single operation and both sides were always aligned. (unless the appi cut them then all bets were off.) BSA BB's had to have the threads cut from each side and often suffered misalignment issues. But because the axle was free floating between the bearings and the bearing surfaces had to "run in" this was generally not a problem. Easily sorted at the first service by a little adjustment. The bearings would wear the correct running path into the race.Today with separate cups that have bearings pressed in on either side and then either threaded in or pressed in, bearing misalignment is still an issue if the threads or pressfit surface are not aligned. Pressfit is easier to correct though.To me, press fitting a bearing into a cup then threading the cup into the frame seems daft. Just as daft as pressing bearings into a cup then pressing the cup into the frame is equally daft. This is just a cheap way to crook misalignment till the bike has been ridden for many miles. I think LOOK have the best system. They mould an alloy sleeve into the frame. That sleeve is made as one part and manufactured to correct bearing tolerances on their BB65 and now BB386. Their BSA bikes also had a moulded in sleeve where the threads are cut in a single operation.Most of these frame manufacturers don't allow correctly for shrinkage of the carbon resin. Trek has a recent history of really poor BB design. BB92 was an absolute joke I wouldn't buy any of their bikes with that system. Bearings too small and often misalignment press fit surfaces or not round. I hope for their sake that they have a threaded alloy sleeve moulded in and then Cut the T47 threads from both sides with the frame not moved around to get the other side cut. If cut in separate operations they'll have a high risk of a misaligned threads that will create a misaligned BB that will be a bigger nightmare to correct. Time will tell. I still like the idea of the BB30 system but Cannondale really stuffed up the execution with maintaining a 68/73mm BB shell when they could have made the shell much wider. That original alloy BB30 shell was clever. Prince Albert Cycles and Eldron 2 Link to comment Share on other sites More sharing options...
DuncanCT Posted June 19, 2020 Share https://www.youtube.com/watch?v=3l6EcBg9EPA&t=663s Link to comment Share on other sites More sharing options...
DuncanCT Posted June 19, 2020 Share Because mating plastic to other plastic then giving them both 90 offcentre cyclic loads a minute wears them out pretty quickly. Neither were designed to be wear surfaces. First they creak, then they creak more then eventually they're so lose they don't creak anymore. On the plus side you can then pop a new SF (slide fit) BB in with two fingers. Manufacturers love them because all they have to do is ream two badly off centre holes into a frame and call it done all the while telling us how much weight they saved us. Are these not just examples of a poorly implemented press fit system? Maybe the argument should be that the tolerances and best practices for a proper press fit system are out of reach of a lot of frame manufacturers and that threaded BB's hide the problems better. Also what is more important to you: quiet, maintenance free use or the lowest possible friction losses? Good example is the Hellbender Neo bottom bracket. It has soild oil bearings. Great for longevity but at the cost of some watts. #marginalgains I understand that press fit is a better system but for the above reasons would rather have a threaded bb frame. Side rant: BB30 systems you are mating the bearings steel inner race to aluminum axle, so if there are any problems, the axle is going to get chewed up. Shimano/BSA systems have a "composite" bushing between the bearing and axle. Edited June 19, 2020 by DuncanCT DieselnDust 1 Link to comment Share on other sites More sharing options...
DieselnDust Posted June 19, 2020 Share Are these not just examples of a poorly implemented press fit system? Maybe the argument should be that the tolerances and best practices for a proper press fit system are out of reach of a lot of frame manufacturers and that threaded BB's hide the problems better. I understand that press fit is a better system but for the above reasons would rather have a threaded bb frame. Side rant: BB30 systems you are mating the bearings steel inner race to aluminum axle, so if there are any problems, the axle is going to get chewed up. Shimano/BSA systems have a "composite" bushing between the bearing and axle. Yebbo goggo...Bearing runout will eat that axle alive. Fortunately you can feel it pretty quickly. With Cannondale cranks the axle as considered expendable. SRAM cranks ......well no hey. You need a new non drive side and for the price a new crank is cheaper. I wish SRAM would go back to the separate axle. FSA....OMG.......I had one where the drive side was bonded on skew. Crank had a visible wobble. Agents at the time would not warranty it. I could not sell it so I turned it into a pizza cutter which a pal "borrowed"...If doing a BB30 crank get a cannondale Hollowgram. Axle is R1500(?) Way cheaper than a new crank.Or stick to 24mm or 25mm axle cranks. Why are cranks so hard to get right? SRAM GXP is appears uses an undersized bearing on the non drive side 7/8th of an inch when the axle is 22mm.. Their 30mm axle cranks are nice and stiff. DUB is a step up. Anyone remember Shimano Octalink? If you want examples of BSA threads that are not aligned find yourself an Octalink cartridge BB and thread it in. It almost never comes out the other side in the centre of the BB shell. Prince Albert Cycles 1 Link to comment Share on other sites More sharing options...
DuncanCT Posted June 19, 2020 Share Apparently "SRAM used a fixed Non drive End bearing to avoid a Shimano patent infringement" for GXP. Not a great system either. Link to comment Share on other sites More sharing options...
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