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Style Works XT Universal 37 Working Version: Features and Benefits



80. Pastoral workers can thus fall into a relativism which, whatever their particular style of spirituality or way of thinking, proves even more dangerous than doctrinal relativism. It has to do with the deepest and inmost decisions that shape their way of life. This practical relativism consists in acting as if God did not exist, making decisions as if the poor did not exist, setting goals as if others did not exist, working as if people who have not received the Gospel did not exist. It is striking that even some who clearly have solid doctrinal and spiritual convictions frequently fall into a lifestyle which leads to an attachment to financial security, or to a desire for power or human glory at all cost, rather than giving their lives to others in mission. Let us not allow ourselves to be robbed of missionary enthusiasm!


Finally, if your target framework implies support for older target frameworks, preprocessor symbols for those older frameworks are emitted. For example, net6.0 implies support for net5.0 and so on all the way back to .netcoreapp1.0. So for each of these target frameworks, the Framework with version minimum bound symbol will be defined.




Style Works XT Universal 37 Working Version



.NET code quality analysis is enabled, by default, for projects that target .NET 5 or a later version. If you're developing using the .NET 5+ SDK, you can enable .NET code analysis for SDK-style projects that target earlier versions of .NET by setting the EnableNETAnalyzers property to true. To disable code analysis in any project, set this property to false.


Studio Display has three USB-C ports that deliver speeds up to 10Gb/s to connect high-speed peripherals, storage, and networking right into the display. A Thunderbolt port enables users to connect Studio Display and any connected peripherals to their Mac with a single cable. The same cable also delivers 96W of power to a Mac notebook, allowing Studio Display to even fast-charge a 14-inch MacBook Pro. And up to three Studio Displays can be connected to MacBook Pro, creating a powerful edit bay or animation workspace.


This comprehensive guide tells you everything you need to know about bottom brackets \u2014 from a breakdown of all the bottom bracket systems available and their compatibility with one another to how a bottom bracket works and how to stop a bottom bracket creaking, this guide has it all.\nIt wasn\u2019t long ago that the only major bottom bracket decisions you had to make were shell width, spindle length, and, in rare cases, English (BSA) or Italian threading. These days, it can feel as though there are as many \u2018standards\u2019 as there are bike brands, with every one of them supposedly being the best option.\nBelow we rundown each of the major bottom bracket systems currently available, along with advantages, disadvantages, notes on compatibility, and some input from their proponents on why they exist.\nWhat is a bottom bracket?\nBikeRadar\u2019s complete guide to headsets\n\n \nConventional\/BSA threaded\nBB90 and BB95\nPF86 and PF92\nBB30\nOSBB (road)\nBB30A and BB30-83 Ai\nPF30\nOSBB (mountain)\nPF30A and PF30-83 Ai\nBBRight\nBB386 EVO\nT47\nThreadfit 82.5\nSRAM DUB\n\n\n \n Before we get stuck into the nitty-gritty of each standard though, we\u2019ve put together this helpful crib sheet that runs through all of the key specifications.\nThe ultimate creaky bottom bracket fix\nRoad bike groupsets: everything you need to know\nBottom bracket standards and compatibility\nISO threaded internal\nProprietary?\u00a0NoBB shell inner diameter\u00a01.37in x 24 TPIBearing inner diameter\u00a0N\/A, internal BBs have integrated spindleBB shell width\u00a068mm road, 73mm mountain, 83mm downhill, 100\/120mm fat bikeInstallation\u00a0Threaded internal bearingsCompatibility\u00a0Square taper, Octalink, ISISOther names\u00a0BSA or BS threadedOther notes\u00a0Bottom bracket must be specced with correct shell width and spindle length\nISO threaded external\nProprietary?\u00a0NoBB shell inner diameter\u00a01.37in x 24 TPIBearing inner diameter\u00a024mm (Hollowtech II), 24\/22mm (GXP), 25mm (Ultratorque\/Powertorque)BB shell width\u00a068mm road, 73mm mountain, 83mm downhill, 100\/120mm fat bikeInstallation\u00a0External cupsCompatibility\u00a0n\/aOther names\u00a0BSA or BS threadedOther notes\u00a0External cups now exist that will take 30mm spindles\nItalian threaded\nProprietary?\u00a0NoBB shell inner diameter\u00a01.375in (34.92mm) x 24 TPIBearing inner diameter\u00a024mm (Hollowtech II), 24\/22mm (GXP), 25mm (Ultratorque\/Powertorque)BB shell width\u00a070mmInstallation\u00a0External or internalCompatibility\u00a0n\/aOther names\u00a0n\/aOther notes\u00a0Can be prone to undoing itself because non-driveside is a standard thread\nBB90\/BB95\nProprietary?\u00a0Yes (Trek)BB shell inner diameter\u00a037mmBearing inner diameter\u00a024mmBB shell width\u00a090mm road, 95mm MTBInstallation\u00a0Pressed bearings with stepped BB shellCompatibility\u00a0Designed specifically for 24mm spindles, no 30mm optionOther names\u00a0n\/aOther notes\u00a0The extra width of the BB cups is replaced with more frame real-estate\nBB86\/BB92\nProprietary?\u00a0NoBB shell inner diameter\u00a041mmBearing inner diameter\u00a024mmBB shell width\u00a086.5mm road, 91.5mm MTB. Other widths may be named according to shell dimensions: 89.5mm, 104.5mm, 107mm, 121mm, 132mmInstallation\u00a0Bearings pressed in cupsCompatibility\u00a0Originally designed for 24mm spindles, but some BBs that fit a 30mm spindle are availableOther names\u00a0PF41 (Hope \u2013 refers to BB shell diameter), PF24 (Chris King \u2013 refers to spindle diameter)Other notes\u00a0Similar to above, but a non-proprietary version with less stringent tolerances\nBB30\nProprietary?\u00a0No (open Cannondale standard)BB shell inner diameter\u00a042mmBearing inner diameter\u00a030mmBB shell width\u00a068mm road, 73mm MTBInstallation\u00a06806 bearings pressed into frame with circlips to locate in BB shellCompatibility\u00a0Designed for specific BB30 cranks, 24mm step-down spacers availableOther names\u00a0n\/aOther notes\u00a0Narrow overall width means longer spindles can be used with appropriate spacers\nBB30A and BB30-83 Ai\nProprietary?\u00a0Yes (Cannondale)BB shell inner diameter\u00a042mmBearing inner diameter\u00a030mmBB shell width\u00a073mm (BB30A), 83mm (BB30-83)Installation\u00a06806 bearings pressed into frame with circlips to locate in BB shellCompatibility\u00a0n\/aOther names\u00a0n\/aOther notes\u00a0Asymmetric BB shell which is wider on non-driveside. Wider overall shell is also claimed to improve bearing support\nPF30\nProprietary?\u00a0No (SRAM)BB shell inner diameter\u00a046mmBearing inner diameter\u00a030mmBB shell width\u00a068mm road, 73mm MTBInstallation\u00a06806 bearings in cupsCompatibility\u00a0Originally designed for BB30 cranksOther names\u00a0n\/aOther notes\u00a0Analogous to BB30 above, but uses pressed cups (with identical bearings) for relaxed manufacturing tolerances\nOSBB (Road)\nProprietary?\u00a0SpecializedBB shell inner diameter\u00a042mmBearing inner diameter\u00a030mmBB shell width\u00a068mmInstallation\u00a0Pressed 6806 bearings with circlips in BB shellCompatibility\u00a0Designed for specific BB30 cranksOther names\u00a0n\/aOther notes\u00a0OSBB for Specialized Road bikes appears to just be BB30. An older Pressfit 61x46mm BB appears to be obsolete\nOSBB (Mountain)\nProprietary?\u00a0SpecializedBB shell inner diameter\u00a046mmBearing inner diameter\u00a030mmBB shell width\u00a073mmInstallation\u00a06806 bearings in cupsCompatibility\u00a0Originally designed for BB30 cranksOther names\u00a0n\/aOther notes\u00a0OSBB for mountain bikes appears to be PF30 (post 2010). An older 84.5x46mm BB appears to be obsolete.\nPF30A and PF30-83 Ai\nProprietary?\u00a0Yes (Cannondale)BB shell inner diameter\u00a046mmBearing inner diameter\u00a030mmBB shell width\u00a073mm (BB30A), 83mm (BB30-83)Installation\u00a06806 bearings in cupsCompatibility\u00a0n\/aOther names\u00a0n\/aOther notes\u00a0Essentially the Pressfit version of BB30A and BB30-83\nBBRight (Direct Fit)\nProprietary?\u00a0No (Cerv\u00e9lo)BB shell inner diameter\u00a042mmBearing inner diameter\u00a030mmBB shell width\u00a079mm (road only)Installation\u00a06806 bearings pressed into frame with circlips to locate in BB shellCompatibility\u00a0BBRight cranks and widerOther names\u00a0n\/aOther notes\u00a0Similar asymmetric concept as Cannondale Ai, but the shell is wider\nBBRight (Press Fit)\nProprietary?\u00a0No (Cerv\u00e9lo)BB shell inner diameter\u00a046mmBearing inner diameter\u00a030mmBB shell width\u00a079mm (road only)Installation\u00a06806 bearings in cupsCompatibility\u00a0BBRight cranks and widerOther names\u00a0n\/aOther notes\u00a0Similar asymmetric concept as Cannondale Ai, but the shell is wider\nBB386EVO\nProprietary?\u00a0No (FSA)BB shell inner diameter\u00a046mmBearing inner diameter\u00a030mmBB shell width\u00a086.5mm roadInstallation\u00a06806 bearings in cupsCompatibility\u00a0Will take 386EVO cranks and traditional external BB cranksOther names\u00a0n\/aOther notes\u00a0Matches the wide bearing spacing of a BSA external BB with a large 30mm spindle\nBB392EVO\nProprietary?\u00a0No (FSA)BB shell inner diameter\u00a046mmBearing inner diameter\u00a030mmBB shell width\u00a091.5mm MTBInstallation\u00a06806 bearings in cupsCompatibility\u00a0Will take 386EVO cranks and traditional external BB cranksOther names\u00a0n\/aOther notes\u00a0Matches the wide bearing spacing of a BSA external BB with a large 30mm spindle\nT47\nProprietary?\u00a0No (Chris King & Argonaut Cycles)BB shell inner diameter\u00a0M47 x 1Bearing inner diameter\u00a030mmBB shell width\u00a068mm road, 73mm MTBInstallation\u00a0Threaded cups with bearingsCompatibility\u00a0Cross compatible dependent on spindle lengthOther names\u00a0Thread Fit 30iOther notes\u00a0Aims to solve creaking issues of press fit systems. Essentially an oversized BSA external BB\nThread Fit 82.5\nProprietary?\u00a0Yes (Colnago)BB shell inner diameter\u00a041mm (when shell is fitted)Bearing inner diameter\u00a024mm (30mm)BB shell width\u00a086.5mm roadInstallation\u00a0Threaded BB shell takes aluminium shell, which is then fitted with BB86 bearing cupsCompatibility\u00a0Originally designed for BB86 cranksets and bearings. New integrated CeramicSpeed BB fits 30mm spindle cranksOther names\u00a0n\/aOther notes\u00a0Threaded shell can be made with better tolerances and can be replaced if it wears out. CeramicSpeed now offers a fully integrated bearing (akin to T47) that will fit 30mm spindles\nWe\u2019ve also included a section on how you can (or can\u2019t as the case may be) change between different bottom bracket standards and an explainer on why there are so many standards in the first place.\nConventional\/ISO\/BSA threaded bottom brackets\nModern, external cup threaded bottom brackets are among the most common of standards. Square taper bottom brackets also fit in most shells designed for external cup bottom brackets, but to keep things simple, we will only cover the modern standard here.\nThe idea is simple, by moving the bearings outboard of the shell, you can then use a much larger spindle. Currently, 24mm is the accepted norm compared to square-taper\u2019s relatively minuscule 17mm diameter.\nExternal bottom brackets for 30mm spindles do exist, such as those from\u00a0White Industries, allowing modern 30mm-diameter axle cranks to be used.\nShimano popularised the concept as Hollowtech II, with the introduction of the XTR M960 group in 2003 \u2014 even now it\u2019s still arguably the gold standard for bottom brackets. In fact, companies such as Santa Cruz continue to stand by it despite the plethora of other options now available.\nThe \u2018new\u2019 bottom bracket standard we can all get behind\n\n Conventional threaded bottom brackets are still very popular, and for good reason. Canyon, for example, stuck with a threaded shell on its top-end Ultimate CF SLX road frame until 2012 Immediate Media\n\u201cThreaded bottom brackets are compatible with the largest range of cranks [and] some press-in bottom brackets have a reputation for creaking,\u201d Santa Cruz global marketing manager, Will Ockelton, tells BikeRadar.\n\u201cPress-in bottom brackets require special tools, which most consumers don\u2019t have [and] they can only be installed a few times before it\u2019s recommended that you replace the bearings [or cups \u2014 ed.]. Most of our bikes come with ISCG tabs, but for the few that don\u2019t, a thread-in bottom bracket still allows for chain guide mounting.\n\u201cA threaded bottom bracket is great because it isolates the bearing from the frameset,\u201d adds Matt Harvey, president of bearing, seal and bottom bracket maker Enduro.\n\u201cBecause you have aluminium threads and surfaces, you can face the shell with a cutter and make it parallel if it is not. The bearing bores are usually round already, with aluminium cups, because it is a machined surface, and if the bearing bores are too tight you can sand them out and get the fit just right for the bearings before you thread them into the frame. You cannot use a facing or cutting tool that I know of in a carbon shell.\u201d\nPros: Easy at-home service; interface surfaces can often be machined; huge selection of parts and accessories\nCons: Heavier than press-fit systems; frame design limited by relatively small-diameter and narrow shell\nCrank designs that will fit: Standard 24mm external type (Shimano Hollowtech II, SRAM GXP, Campagnolo Ultratorque and Powertorque, FSA MegaExo, Race Face X-Type, etc), square taper, ISIS, BB386EVO, BB392EVO many others. Crucially external cups that fit 30mm spindles do exist.\nA note on other threaded bottom bracket standards\nTo make matters even more confusing, there exists a number of other threaded bottom bracket standards.\nExcluding the relatively new T47 standard (more on that later), the one you\u2019re most likely to come across is the Italian threaded bottom bracket.\nTo keep matters simple, we\u2019ve put together a simple explainer on this slightly esoteric of standards here.\nWhat is the difference between an Italian and BSA bottom bracket?\nBB90 and BB95 bottom brackets\nTrek introduced the proprietary BB90 standard in 2007 on the revamped Madone and soon followed with the mountain bike-specific BB95.\nInstead of bearing pressed into aluminium cups that were then threaded into the frame, Trek pressed the bearings directly into the frame.\nBearing seats were moulded into the carbon frame structure to save weight, and bottom bracket shell width ballooned to 90mm on road bikes and 95mm on mountain bikes, creating more real estate for frame tubes and suspension pivots.\nEffectively,\u00a0the space previously taken up by the bearing cups can now be used as frame real-estate, allowing larger (and stiffer) tubes to be used.\nIs Trek all-in on T47? Why I won\u2019t miss BB90, the worst bottom bracket standard\n\n Trek\u2019s BB90 system uses the same bearings and bearing locations as a conventional threaded system, but eliminates the cups entirely. Bearings are pressed directly into precision-molded carbon seats Immediate Media\n\u201cThe most significant [advantage] is a stiffer frame,\u201d says Trek mountain bike product manager John Riley. \u201cSecondarily, BB90\/95 offers a lighter overall solution by replacing traditional alloy bearing cups with integrated carbon bearing bores. It also provides a simplified installation process.\u201d\nAside from omitting the cups, the BB90\/95 setup is functionally identical to conventional threaded bottom brackets, in that it uses the same bearings and the same bearing locations as before. Crankset compatibility is thus unchanged, although you do lose the ability to run chain guides that sandwich between the driveside cup and frame.\nThis system is not without its issues however, with shells becoming oversized (due to wear) being a relatively common problem (leading Trek to release the very slightly oversized V2 bearings to compensate).\nPerhaps partly due to these issues, Trek has, in fact, recently abandoned this bottom bracket standard on its Domane endurance road bike platform for 2020, in favour of the T47 threaded standard. It will be interesting to see if this trend carries over to future models in its range.\nPros: Lighter than conventional setups but retains compatibility with \u2018legacy\u2019 cranksets; creates a wider BB shell without affecting crank width\nCons: Can\u2019t use cup-mounted chain guides; shell is wider but still small in diameter; requires a separate bearing puller and press for service, bearing bores can wear out and loose tolerances\nCrank designs that will fit: Standard 24mm external-type only. A GXP conversion kit is also available\nBB86 and BB92\u00a0bottom brackets\nVery closely related to Trek\u2019s BB90\/BB95 system is the BB86\/BB92 standard used by Scott, Giant, Pivot, and many others.\nOnce again, the bearings and their locations are identical to those of conventional threaded bottom brackets, only they\u2019re mounted in small composite cups before being pressed into the frame.\nThe advantages are similar to those for Trek\u2019s BB90\/95; a wider bottom bracket shell that doesn\u2019t otherwise affect crank width, plus lighter weight compared with threaded alloy cups.\nFrom a manufacturing standpoint, BB86\/92\u2019s dimensional tolerances aren\u2019t as stringent as BB90\/95\u2019s, and it\u2019s easier to adapt the system into alloy frames. So long as you have a concentric bore of the right diameter, parallel faces, and a proper shell width, you\u2019re good to go.\n\n PF86\u2019s wider shell allows the chainstays to be pushed further apart \u2013 a big advantage for \u2018cross bikes Immediate Media\n\u201cBecause of this technology, we\u2019re able to improve pedalling stiffness [by about] 10% on some of our frames, over traditional threaded bottom brackets,\u201d says Giant global marketing director Andrew Juskaitis. \u201c[PF86\/92 is] less subject to tolerances, too, and is able to take up +\/- 0.5mm of [shell width] discrepancy.\u201d\nScott US marketing and PR director Adrian Montgomery touts similar reasons for his company choosing BB86\/92 over other standards:\n\u201cWe can create frames with a wider bottom bracket shell, thus adding stiffness to the entire structure as the adjoining tubes can also be wider. We can do this without creating our own crank spindle standard because it adheres to the same spindle that a threaded BB uses. It\u2019s also lighter than a threaded BB because we\u2019ve removed the alloy material that held the bearings outside the shell [and] it costs less to do a press-fit bottom bracket in regards to manufacturing. Disadvantages? None that I can see.\u201d\nThe road standard has an 86.5mm shell width (hence BB86) whilst the mountain bike standard has a 91.5mm shell width. A number of other shell widths may also exist, though they all use the same bearing cups.\nMore recently, bearings have shown up that allow a 30mm spindle to be used. The dimensional restriction mean the bearings are generally quite small, as the system was designed around 24mm spindles. This can lead to reduced bearing lifetimes.\nThis system has a number of different names depending on who you talk to. It is also called PF86, PF92, PF24 (Chris King) and PF41 (Hope).\nPros: Same as BB90\/95\nCons: Same as BB90\/95 in theory, but in practice there are generally less issues experienced due to the less stringent tolerances\nCrank designs that will fit: Standard 24mm external-type, 30mm spindle bottom brackets are available for e.g. BB386 EVO, BB392EVO\nBB30 and OSBB\u00a0\u00a0bottom brackets\nSeveral companies have dabbled in alternative bottom bracket standards over the years (Gary Fisher, Klein, and Merlin, to name just three) but it wasn\u2019t until Cannondale released its then-proprietary BB30 system as an open standard in 2006 that something actually stuck.\nBB30\u2019s bearing cartridges press directly into a precision-fit shell, as with Trek\u2019s BB90\/95 system \u2014 albeit with the additional aid of two pairs of snap-rings\/C-Clips.\nBut here it\u2019s the shell and spindle diameters that increase in size, not the shell width.\nThe key benefits are lighter weights owing to the larger, 30mm-diameter aluminium spindle and the elimination of separate bearing cups. Plus, because the shell is still just 68mm wide, the cranks can also be made to provide more heel clearance \u2014 or, depending on the crank design, an even a narrower stance width (commonly referred to as Q factor).\n\n Proper BB30 bottom brackets require extensive and careful machining inside the shell in order to work properly \u2013 and quietly Immediate Media\n\u201cThe idea was that, since Cannondale had control of both the frame and crank manufacturing, we could use system integration to design a superior solution, even if that meant not relying on a traditional industry standard,\u201d says Cannondale vice president of R&D, Chris Peck. \u201c[Advantages are] a lighter and stiffer crank with the 30mm alloy spindle; more room in the bottom bracket area to attach larger down tubes, seat tubes, and chainstays; and very low bottom bracket weight.\u201d\n\u201c[Our] Hollowgram SiSL2 crank with SpideRing weighs 484g. By comparison, Dura-Ace 9000 weighs around 678g [we recorded 637g in our review \u2013 ed]. In addition to weight, another BB30 advantage is stiffness. By increasing the spindle diameter, you increase its resistance to twisting, which is where the bulk of the deflection in a crankset comes from. Roughly 70% of total deflection measured at the pedal comes from axle twist.\u201d\nBB30 shells, however, do require more stringent dimensional tolerances to work well, meaning that they\u2019re more expensive to manufacture. Moreover, with the notable exception of Felt, which uses a carbon tube, BB30 also usually employs an alloy shell insert that has to be bonded or co-moulded into an otherwise carbon frame.\nSpecialized\u2019s uses this standard for some of its high-end road bikes, but calls it OSBB.\nPros: Lighter weight; more resistant to axle twist; more heel clearance; larger-diameter shell and spindle; potential for narrower pedal stance width\nCons: Shell still just 68mm wide; metal-on-metal interfaces can be prone to creaking; requires a separate bearing puller and press for service; requires high manufacturing tolerances; bearing seats can\u2019t easily be faced post-manufacturing\nCrank designs that will fit: BB30, BB386 EVO, standard 24mm external-type, Specialized OSBB, BBRight. Can be adapted to almost any standard with suitable adapters.\nBB30A and\u00a0BB30-83 Ai\u00a0bottom brackets\nMore recently, Cannondale announced a variant of BB30 called BB30A. This uses a shell that\u2019s 5mm wider than the original but it\u2019s an asymmetrical layout that only adds those extra millimetres on the non-driveside. According to Cannondale, this allows for wider bearing spacing and better spindle support (which should improve bearing longevity).\nOther critical dimensions, such as bearing outer diameter and thickness, remain unchanged and there\u2019s also no difference in pedal stance width or ankle clearance (in most cases).\nThat extra 5mm can complicate crank compatibility, however. BB30-compatible cranks that feature axle spacers on the non-driveside (such as from Cannondale and SRAM) will work just fine because all you\u2019ll have to do is remove spacers as needed to accommodate the extra width, but BB30 cranks without such spacers (such as from FSA and Specialized) won\u2019t work.\nThankfully, many newer BB30-compatible cranks now feature extra-long spindles for wider compatibility and those will install just fine.\n\n\n The new Cannondale SuperX uses the brands BB30-83 Ai standard Robert Smith \/ Immediate Media\n\n\nCannondale also introduced another bottom bracket standard in the form of BB30-83 Ai.\n\nFirst used on the brand\u2019s SuperX \u2018cross bike, the standard works in exactly the same way as BB30A, but sees the shell ballooned out to 83mm wide, improving tyre clearance and, supposedly, stiffness.\nPros: Lighter weight; more resistant to axle twist; more heel clearance; larger-diameter shell and spindle; potential for narrower pedal stance width\nCons: Metal-on-metal interfaces can be prone to creaking; requires a separate bearing puller and press for service; requires high manufacturing tolerances; bearing seats can\u2019t easily be faced post-manufacturing; not all BB30 cranks will fit\nCrank designs that will fit: BB30 (some), BB386 EVO, standard 24mm external-type, BBRight\nPF30 and OSBB\u00a0bottom brackets\nSRAM addressed BB30\u2019s stringent dimensional tolerances and associated manufacturing costs with the advent of PressFit 30 in 2009. Just as with PF86\/92, PF30 is analogous to BB30 in that the bearings and bearing locations are identical, but with the addition of intermediary composite cups that allow for looser frame tolerances.\nNot surprisingly, then, PF30 has gained widespread traction in the industry, particularly with smaller manufacturers who can\u2019t afford high reject rates.\nSpecialized uses PF30 for its high-end mountain bike, confusingly also calling it OSBB though it is a different standard to the OSBB standard found on its road bike.\n\u201cI think it\u2019s more about the simplicity of the manufacturing process,\u201d says Drew Guldalian of Pennsylvania-based custom builder Engin Cycles. \u201cBoring out a [standard] BB30 is not impossible, but in my opinion it\u2019s an unrealistic task from a manufacturer\u2019s standpoint that needs to do something to make money.\n\u201cWith the PressFit 30, they\u2019re using the same technology with the larger bearings and the same technology with the bearings living inside the frame, but they\u2019re utilizing the nylon to their advantage where you have a more realistic tolerance.\u201d\n\u201cPressFit 30 fundamentally provides all the most significant advantages of BB30 but requires much less precise machining of the bottom bracket shell area, as the bearings come inserted into plastic cups that are easier to fit into the frame and less delicate than standalone bearing,\u201d adds SRAM drivetrain product manager Chris Hilton. \u201cPF30 bottom brackets also have an integrated sealing system, which helps prolong bearing life.\u201d\nCannondale\u2019s Chris Peck provided BikeRadar with specific details. While BB30\u2019s bearing bore tolerances are 41.96 +0.025\/-0mm (meaning the bore can be slightly oversized but not undersized), PF30\u2019s requirements are 46.00 +0\/-0.05mm \u2013 exactly half as rigorous.\nSpecialized\u2018s OSBB system is nearly identical to BB\/PF30 but with a few key differences, according to the company\u2019s director of advanced research, Chris D\u2019Aluisio.\nInterview: SRAM\u2019s Chris Hilton\n\n BB30\u2019s larger 30mm-diameter spindle, compared to the standard 24mm size, allows the use of lighter alloy Immediate Media\n\u201cThe 30mm bearing is a good choice when using thinwall aluminium spindles,\u201d he says, \u201cand the narrow bearing stance (relative to outboard bearings) works perfectly with our carbon arm design needing to make the turn into the spindle. The OSBB is basically the same as BB30 but with a little tighter tolerances and a 0.5mm difference in the clip-to-clip dimension. Cranks of both systems are compatible with each other.\u201d\nD\u2019Aluisio even argues that OSBB offers alignment advantages compared with threaded shells:\n\u201cThe tolerances are not too different but the way they\u2019re measured is. They both have the same needs for concentricity and placement relative to the frame. The threads are at a disadvantage in that they need to be machined from both sides and have a hard time sharing a centerline, whereas our OSBB is machined from one side all at once \u2014 and round holes are easy to measure.\u201d\nPros: Same as BB30 but with lower costs, easier assembly, and the potential for additional bearing seals integrated into the cup\/bearing assembly\nCons: Standard-width shell; requires a separate cup remover and press for service\nCrank designs that will fit: BB30, BB386 EVO, standard 24mm external-type, Specialized OSBB, BBRight\nPF30A and PF30-83 Ai\u00a0bottom brackets\nThis is essentially the same as the BB30A and BB30-83 Ai Cannondale system described above, except that it uses bearing cups rather than bearings pressed directly into the frame.\n\n The new Cannondale F-Si uses a PF30-83 Ai bottom bracket Jack Luke \/ Immediate Media\nSimilarly, it\u2019s largely based on the PF30 design, though with a 5mm wider, asymmetric bottom bracket shell \u2014 73mm for PF30A and 83mm for PF30-83.\nPros: As for BB30A and BB30-83 Ai\nCons:\u00a0Similar to BB30A and BB30-83 Ai, though press-fit design relaxes tolerance requirements\nCrank designs that will fit:\u00a0BB30 (some), BB386 EVO, standard 24mm external-type, BBRight\nBBRight\u00a0bottom brackets\nMost bottom bracket fitments incorporate bearings that are symmetrically positioned about the frame\u2019s centerline. Much like the Cannondale design,\u00a0Cerv\u00e9lo tipped that apple cart in 2010, however, with the introduction of BBRight.\nBBRight shares its 30mm-diameter alloy spindle, cartridge bearings, and driveside bearing location with PF30 \u2014 in fact, the bottom bracket cups are identical to PF30.\nHowever, the non-driveside bearing is pushed outward by 11mm \u2014 the same as conventional threaded, BB90, and PF86 bottom brackets. This makes it something of a hybrid between the two widely accepted systems.\n\n Cerv\u00e9lo introduced the new BBright system on the R5ca, and while it offers some sound engineering advantages, other companies have been slow to adopt it Immediate Media\n\u201cBBRight uses the 11mm space occupied by an external bottom bracket\u2019s left bearing cup to let the designer widen the frame tubes that connect to the bottom bracket shell: down tube, left chainstay and seat tube,\u201d says Cerv\u00e9lo race engineer Damon Rinard. \u201cAll these can be 11mm wider now. In the case of the chainstay, that\u2019s nearly double the width at an important and highly loaded point \u2014 the junction with the bottom bracket \u2014 which has a several-fold beneficial effect on stiffness.\u201d\n\u201cThe resulting increase in moment of inertia has gained us so much stiffness and strength that the left chainstay weighs less than the right, despite being stiffer and stronger,\u201d he continues. \u201cBecause stiffening either chainstay stiffens the frame, the net result is a substantial increase in the frame\u2019s bottom bracket stiffness, together with a small reduction in frame weight.\u201d\nRinard insists this revised bearing spacing comes with no functional downsides, either:\n\u201cThis performance boost comes with no other changes to basic dimensions: the left bearing stays in the same spot; the aluminium cup is simply replaced with carbon frame now. And since the bearing\u2019s in the same spot, the lateral position of the left crank isn\u2019t changed at all, so Q-factor is also unchanged. Your feet are in exactly the same place as before.\u201d\nBBRight is available in two incarnations. The direct fit version uses the same 6806 bearings from a BB30 bottom bracket, which are pressed directly into the frame.\nThe press fit version uses removable bottom bracket cups, similar PF30 and is used on all other Cerv\u00e9lo frames and has also been adopted by some 3T designs.\nFrom the outset, Cerv\u00e9lo introduced BBRight as an open standard that anyone could jump onto. While it seems to make good engineering sense, however, other bike companies have been slow to come on board.\nPros: Stiffer than BB\/PF30, in theory, without impacting other attributes; good crank compatibility, cheaper to manufacture than threaded or BB30\nCons: Questionable longevity; requires a separate cup remover and press for service\nCrank designs that will fit: BBRight, BB386 EVO, standard 24mm external-type\nBB386 EVO & BB 392 EVO\u00a0bottom brackets\nBB386 EVO and BB392 EVO, introduced in 2011, take the oversized principle to extremes. The bearings have the same 86\/92mm spacing, width-wise, as conventional threaded external BB, BB90\/95, and PF86\/92 formats, but it uses BB\/PF30\u2019s bigger 30mm diameter spindle.\nAs stiffness is directly tied to cross-sectional size it\u2019s no surprise that, theoretically, BB386 EVO has the most to offer, with both the added shell width and diameter that many frame-makers yearn for.\nIn addition, it uses the same bearings and cups as PF30 and BBRight and, thus, the same manufacturing tolerances and required tools.\n\n The BB386 EVO bottom bracket system actually uses the same cups as PressFit 30 Immediate Media\n\u201c[BB386 EVO] allows us to go wider, which in turn opens up big opportunities in terms of stiffness and strength in the bottom bracket\/chainstay area,\u201d says BH president and CEO Chris Cocalis (Cocalis holds the same position with Pivot Cycles, whose frames are built around the more mountain bike-friendly PF92 format). \u201cWith bigger cross-sections driving stiffness, we also have more flexibility in being able to tune ride quality with the carbon layup.\u201d\n\u201cFor us, there are no disadvantages versus a threaded design or a standard BB30. We are able to have a full carbon shell with no metal bonded into the frame, which makes for a stronger, lighter frame structure.\n\u201cWith our manufacturing methods, we also have no issues holding tolerances.\u00a0[BB386 EVO] wasn\u2019t designed as a cost reduction, but not having to post bond an aluminium shell into the frame and make sure the facing and threads are correct is slightly less expensive and much more reliable.\u201d\nCrank compatibility is another BB386 EVO strongpoint. Despite the bulbous dimensions, the shell will accept most modern crankset fitments save for dedicated BB30\/PF30 and BBRight designs.\n\u201cThe BB386 EVO cranks are compatible with almost every BB shell standard (BSA, BB30, PF30, BB86),\u201d says Jason Miles of FSA. \u201cWe currently make bottom brackets and adaptors for BSA, BB30, and PF30 frames and are working on BB86 bottom brackets. Frames with BB386 EVO shells should be able to run almost any crank. We currently make adaptors to fit Shimano, Campagnolo, and SRAM 24mm spindle cranks.\u201d\nWhile the surrounding frames should be stiffer than those built around narrower BB\/PF30 or threaded shells, Miles admits that the BB386 EVO crankset actually takes a slight step back in that regard, but only when viewed independently of the entire system. The straighter arms also have less ankle and heel clearance than those narrower formats.\n\u201cBecause the crank arms are straighter, we can make them lighter than BB30 ones,\u201d he says. \u201cBut because the BB386 EVO spindles are longer than BB30 ones, they aren\u2019t as stiff. Total stiffness is not a measure of crank stiffness alone, though. When you factor in the stiffness gains from a wider shell, the overall stiffness will be highest when BB386 EVO frames meet BB386 EVO cranks.\u201d\nPros: Theoretically the best in terms of frame stiffness; reduced manufacturing costs; generous crankset versatility\nCons: Heel clearance isn\u2019t as good as BB30; requires a separate cup remover and press for service\nCrank designs that will fit: \u00a0BB386 EVO\/BB392 EVO specific, standard 24mm external-type (can be adapted), BBRight,\u00a0BB30 (axle width dependant),\nT47\u00a0bottom brackets\nDesigned in conjunction with Chris King and Argonaut Cycles, T47 \u2013 announced in 2015 \u2013 is the most recent offering hoping to become the next standard. T47 bottom brackets, aka Thread Fit 30i, use the same 46mm internal diameter as PressFit 30, but they thread into frames rather than being pressed in.\nThis standard is also sometimes known as Threadfit 30i.\n\n Chris King and Argonaut Cycles\u2019 threaded T47 is the latest BB on the block Courtesy\nThe design comes about as a solution to the well documented creaking issues associated with oversized press-fit systems. While these issues are near always the result of poor tolerances, the T47 standard promises to fix the creaking issue without sacrificing the benefits of an oversized interface.\nAs it stands, this new standard may just become the hot new thing among smaller manufacturers of metal bikes.\nThe need for a heavier metal interface looked like a limiting factor for mass-produced carbon bikes, but with a manufacturer like Trek on now on board (as mentioned above, its 2020 Domane features a T47 BB) that could all be about to change.\nPros: Vast crankset compatibility, open standard, threaded design easy to service and prevent from creaking, same dimensions as PF30\nCons: New tooling needed for manufacture, requires metal threads, weight\nCrank designs that will fit: All (dependent on axle width)\nColnago ThreadFit 82.5 bottom brackets\nThreadfit 82.5 is not really a new standard in that it is compatible with BB86 cranksets and bearings.\nRather than press the BB86 bottom bracket directly into the frame, the ThreadFit system threads an aluminium shell into the frame first, which provides the interface for the bearings to sit in.\n\n Colnago Threadfit 82.5 uses an oversized, threaded bottom bracket shell Jack Luke \/ Immediate Media\nAccording to Colnago, this allows dimensions and tolerances to be controlled more accurately. Additionally, it allows the bottom bracket interface to be replaced easily if it wears over time or after multiple bottom bracket replacements.\nWith the release of the C64 bike, Colnago, in collaboration with CeramicSpeed, designed a ThreadFit 82.5 bottom bracket that fits the bearings directly into the shell that threads into the frame \u2014 effectively a proprietary T47 design. This also allows a larger 30mm spindle crank to be installed.\nPros: As for PF86\nCons: As for PF86\nCrank designs that will fit: Standard 24mm external-type, Shimano, SRAM GXP, Campagnolo and 30mm spindle cranks for CeramicSpeed bottom bracket\nSRAM DUB bottom brackets (Durable, Unifying Bottom Bracket)\nDUB (Durable, Unifying Bottom bracket) may sound like a new standard, but really it\u2019s a new axle diameter specification for mountain bike cranks (in 2019, SRAM also started rolling out DUB cranksets in the road line-up).\nSRAM claims that the focus on optimising the bearings resulted in a spindle diameter of 28.99mm. This places is right between SRAM\u2019s old 24mm GXP cranks and 30mm spindles of modern cranks.\nThankfully DUB has been designed with major bottom bracket standards in mind, allowing the cranks to be fitted to the most common designs with the choice of the appropriate bottom bracket.\n\n SRAM DUB has bottom brackets for most standards, that thankfully all fit the same DUB cranksets Alex Rafferty \/ SRAM\nDUB is compatible with BSA threaded, PF86, PF92, BB30 (73mm shell) and PF30 (73mm shell) bottom brackets and cranksets are completely interchangeable between the different standards.\nThis is achieved by placing the bearings at the same axial location along the bottom bracket axis \u2014 in the case of BB30 and PF30 bottom brackets, that results in the bearings being located outboard of the frame.\nPros: Claims of improved sealing and durability, compatible with major BB standards, cross-compatibility for DUB cranksets\nCons: Proprietary system\nCrank designs that will fit: DUB\nWill my cranks fit my bike?\nWhile cranks designed specifically for your bottom bracket will fit, at some point you may want or need to adapt \u2018non-standard\u2019 cranks to your bottom bracket. It\u2019s hard to confirm compatibility without looking at the specific combination of crankset and bottom bracket, but there are some rules of thumb we can apply.\nGenerally, your replacement cranks may have the same or smaller spindle diameter, and the same or longer spindle length than the system your bottom bracket is designed around.\nFor example, a BB30\/PF30 bottom bracket has the narrowest shell width of any of the standards, whilst being designed for large 30mm spindles. That means it should be able to take most cranks with appropriate adapters and spacers to take up the \u2018space\u2019 of a narrower and\/or longer spindle.\nHowever, it\u2019s worth bearing in mind that using a stack of spacers may not be the optimum solution for performance (read stiffness) and reliability.\nOn the other hand, a BB30 crankset, being specifically designed for a BB30 bottom bracket is generally not adaptable to many other systems, due to the short spindle length matching the narrow shell width. Newer BB30 cranks have started using longer spindles to make them a bit more versatile.\nAt the other end of the spectrum, Trek\u2019s proprietary BB90\/BB95 bottom bracket is designed around a wide shell and narrow spindle, meaning it is limited to traditional 24mm spindle cranks.\nVarious other bottom bracket standards lie between these two extremes. Take these guidelines with a pinch of salt and always be sure to double check what you can fit before committing to a new crankset.\nHow do I change to a different crankset?\nAs you\u2019ve likely noticed in the footnotes above, most of the bottom bracket standards offer a fairly wide range of options in terms of crankset choice. And, not surprisingly, several companies are at the ready to help you make those changes.\nCurrent players in the mix-and-match field include Wheels Manufacturing, Rotor, Praxis Works, Enduro Bearings and even house brands of third-party distributors such as Quality Bicycle Parts\u2018 Problem Solvers.\n\n Numerous adaptors are available to convert from one bottom bracket system to another Immediate Media\nChanging between setups typically requires some type of adapter. Or, in ideal cases, bottom bracket bearing assemblies that directly convert from one system to another, such as Praxis Works\u2019 BB\/PF30-to-24mm assembly.\nIn general, though, the guideline is the same: try to minimise the number of parts involved. More parts added on top of each other results in greater tolerance stack-ups, plus more interfaces that could potentially creak.\nWhy are there so many bottom bracket standards?\nThere\u2019s nothing wrong with threaded bottom brackets, per se, and it\u2019s worth noting that none of the proponents of alternative systems cast threaded systems as being fatally flawed. They do, however, note the system\u2019s inherent limitations in terms of frame design, which is why more companies \u2014 particularly ones striving to be on the cutting edge \u2014 continue to embrace non-threaded formats.\nHow companies decide to go about that \u2014 and precisely what design features they want \u2014 is the real issue, because everyone seems to have their own ideas on how to achieve the same goals (less weight, more stiffness, and lower manufacturing costs).\n\u201cThe explosion of bottom bracket standards reflects the various design objectives and manufacturing competencies of individual frame and component brands,\u201d says Eric Doyne, US PR representative for Shimano. \u201cShimano sees and values the importance for consumers to be able to easily source a frequent consumption article like the bottom bracket.\n\u201cThe explosion of standards is not good for consumers or dealers,\u201d Doyne continues. \u201cThe bottom line is that bike companies are driving the standards. Threaded systems have very few limitations \u2014 they are easily cleaned and repaired at the shop level, and they do not affect the bearing fit.\u201d\nIn concept, at least, all of the standards we\u2019ve covered are functionally sound. But the realities of relaxing tolerances can create other issues.\nFor example, save for Shimano, Rotor, Specialized, and some FSA models that use adjustable effective crank arm-to-crank arm distance, most of these alternative systems require wave washers or compressible spacers to account for inherent shell width variability (Magic Motorcycle used precision micro-shims back in the day, and some third parties offer similar systems for modern cranksets).\n\n The explosion of new bottom bracket standards has also required the introduction of new tools to go with them Immediate Media\nThings work okay if the installation is done correctly. But, if not, you could still end up with lateral play under load (possibly resulting in dropped chains) or bearings that are too heavily preloaded (decreasing bearing lifespan).\nWeather-sealing can be a problem, too. Integrated cup and bearing systems at least have the potential for good barriers against dirt and moisture, depending on the design, but bottom bracket standards that rely solely on bearings pressed directly into the frame sometimes have to make do with the typically inadequate seals on the bearing cartridges themselves.\nSome designs even offer discipline-specific advantages. For example, BB30 offers the narrowest potential Q-factor, while wider shells allow for greater chainstay spacing, for more tire clearance on mountain bike hardtails and cyclocross frames.\nFinally, there are aesthetic considerations. Road companies often gravitate towards BB30 for the sleek, narrow form factor, while smaller builders dealing primarily in steel might prefer the more proportional look of a threaded shell. Carbon companies looking to maximise their stiffness (or stiffness-to-weight) figures generally just want to go bigger in some way.\nAs to which bottom bracket standard is \u2018best\u2019, the answer is undeniably straightforward: it depends.\nThis article was first published in March 2013 and was most recently updated in January 2020","image":"@type":"ImageObject","url":"https:\/\/images.immediate.co.uk\/production\/volatile\/sites\/21\/2019\/03\/01_ultimate_guide_to_bottom_brackets-1552559704935-kk78dn83ckn0-65e4441.jpg?quality=90&resize=768,574","width":768,"height":574,"headline":"The complete guide to bottom bracket standards","author":["@type":"Person","name":"Benedict Pfender"],"publisher":"@type":"Organization","name":"BikeRadar","url":"https:\/\/www.bikeradar.com","logo":"@type":"ImageObject","url":"https:\/\/images.immediate.co.uk\/production\/volatile\/sites\/21\/2019\/03\/cropped-White-Orange-da60b0b-04d8ff9.png?quality=90&resize=265,53","width":182,"height":60,"speakable":"@type":"SpeakableSpecification","xpath":["\/html\/head\/title","\/html\/head\/meta[@name='description']\/@content"],"url":"https:\/\/www.bikeradar.com\/advice\/buyers-guides\/the-complete-guide-to-bottom-bracket-standards\/","datePublished":"2019-03-14T00:01:00+00:00","dateModified":"2022-10-21T16:39:39+00:00"}] The complete guide to bottom bracket standards Want to know your BSA from your BB90? 2ff7e9595c


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