{"id":63299,"date":"2026-08-18T09:31:30","date_gmt":"2026-08-18T07:31:30","guid":{"rendered":"https:\/\/cyclingceramic.com\/?p=63299"},"modified":"2026-09-10T15:09:10","modified_gmt":"2026-09-10T13:09:10","slug":"tipos-de-eje-de-pedalier","status":"publish","type":"post","link":"https:\/\/cyclingceramic.com\/es\/bottom-bracket-types-comparison\/","title":{"rendered":"Bottom Bracket Types Comparison"},"content":{"rendered":"\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"63299\" class=\"elementor elementor-63299\" data-elementor-post-type=\"post\">\n\t\t\t\t<div class=\"elementor-element elementor-element-6832daf e-con-full e-flex e-con e-parent\" data-id=\"6832daf\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-a1df578 elementor-widget elementor-widget-html\" data-id=\"a1df578\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"html.default\">\n\t\t\t\t\t<style>\n.green { color: #2d7a2d; font-weight: 500; }\n.red { color: #c0392b; }\n.callout { background: #f0f7f0; border-left: 4px solid #435655; padding: 16px 20px; margin: 24px 0; border-radius: 4px; }\n.bold-row td { font-weight: 600; border-top: 2px solid #435655; }\ntable { width: 100%; border-collapse: collapse; margin: 24px 0; }\nth { background: #435655; color: #fff; padding: 10px 14px; text-align: left; }\ntd { padding: 9px 14px; border-bottom: 1px solid #e0e0e0; }\n.faq-section h3 { color: #435655; margin-top: 20px; }\n<\/style>\n<script type=\"application\/ld+json\">\n{ \"@context\": \"https:\/\/schema.org\", \"@type\": \"BlogPosting\", \"headline\": \"Bottom Bracket Types Comparison\", \"description\": \"Every bottom bracket type compared: BSA, ITA, BB86, BB30, PF30, 386EVO, BBRight, T47 and T45, with the dimensions that identify each one on your frame.\", \"url\": \"https:\/\/cyclingceramic.com\/bottom-bracket-types-comparison\/\", \"datePublished\": \"2026-08-18\", \"dateModified\": \"2026-08-18\", \"author\": {\"@type\": \"Person\", \"name\": \"Ilan Lemos De Abreu\"}, \"publisher\": {\"@type\": \"Organization\", \"name\": \"CyclingCeramic\", \"url\": \"https:\/\/cyclingceramic.com\", \"logo\": {\"@type\": \"ImageObject\", \"url\": \"https:\/\/cyclingceramic.com\/wp-content\/uploads\/cyclingceramic-logo.png\"}}, \"mainEntityOfPage\": {\"@type\": \"WebPage\", \"@id\": \"https:\/\/cyclingceramic.com\/bottom-bracket-types-comparison\/\"}, \"about\": [{\"@type\": \"Thing\", \"name\": \"Bottom bracket\"}, {\"@type\": \"Thing\", \"name\": \"Bicycle frame standards\"}, {\"@type\": \"Thing\", \"name\": \"Crankset\"}], \"keywords\": \"bottom bracket types, bottom bracket standards, BSA, BB86, PF30, BB30, T47, 386EVO, BBRight, press fit bottom bracket\" }\n<\/script>\n<script type=\"application\/ld+json\">\n{ \"@context\": \"https:\/\/schema.org\", \"@type\": \"FAQPage\", \"mainEntity\": [\n{\"@type\": \"Question\", \"name\": \"How many bottom bracket types are there?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"There is no fixed count, because frame brands keep adding variants, but around a dozen standards cover almost every road and gravel bike in use. The threaded family includes BSA English, Italian ITA, T47 in its external and internal cup versions, and frame-specific threaded types such as the T45 ThreadFit used by Colnago. The press-fit family includes BB86 and BB92, BB30, PF30 and the asymmetric PF30A, 386EVO, BBRight, and direct-press frame standards such as Trek BB90. Each one is defined by shell width, shell bore or thread, and the crank spindle it accepts.\"}},\n{\"@type\": \"Question\", \"name\": \"How do I know which bottom bracket type my frame uses?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"Measure two things with the crank and bottom bracket removed: the width of the bare shell and its inner diameter or thread. A 68 mm shell with visible threads is BSA, 70 mm threaded is Italian, 86.5 mm with a smooth 41 mm bore is BB86, 68 mm with a smooth 46 mm bore is PF30, 68 mm with a smooth 42 mm bore is BB30, and 86.5 mm with a 46 mm bore is 386EVO. Then check what spindle your crankset uses, since the same shell accepts different bottom brackets for a 24 mm Shimano, 24x22 mm SRAM GXP, 28.99 mm SRAM DUB or 30 mm spindle.\"}},\n{\"@type\": \"Question\", \"name\": \"What is the difference between BB86 and PF30?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"Both are press-fit, but they are built around different spindle sizes. BB86 has a narrow 41 mm bore in an 86.5 mm wide shell and was designed around 24 mm Shimano-style spindles, with the bearings sitting inside small pressed cups. PF30 has a much larger 46 mm bore in a 68 mm shell and was designed around 30 mm spindles, which are lighter and stiffer for the same weight of material. The wider bore is also why PF30 is more sensitive to frame tolerance, since a larger diameter magnifies any error in roundness.\"}},\n{\"@type\": \"Question\", \"name\": \"Is T47 better than BSA?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"T47 keeps the large bearing diameter of press-fit designs while threading into the frame like BSA, so it accepts 30 mm spindles that a 1.37 inch BSA shell cannot easily take, and it can be installed and removed with normal shop tools. BSA remains the simplest and most widely supported standard, with parts available everywhere. Neither is universally better, and in practice you do not choose: the frame decides. What both share is that a threaded interface can be tightened to a defined torque, which is why serviceability is generally easier on both than on a pressed interface.\"}},\n{\"@type\": \"Question\", \"name\": \"Can I convert my bottom bracket to a different standard?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"You cannot change the frame shell itself, but you can often change which crankset it accepts, and that is what most riders actually need. A single shell standard is covered by several bottom brackets, one per spindle diameter, so a BB86 frame can run a 24 mm Shimano crank, a 24x22 mm SRAM GXP crank, a 28.99 mm DUB crank or, with the right unit, a 30 mm spindle crank. Converting between shell standards, such as a press-fit shell to a threaded interface, requires a dedicated conversion kit and is a workshop job.\"}}\n] }\n<\/script>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-1914efd e-flex e-con-boxed e-con e-parent\" data-id=\"1914efd\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-d2d6980 elementor-widget elementor-widget-text-editor\" data-id=\"d2d6980\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<article><section id=\"section-intro\"><p>Bottom bracket standards look chaotic because the names are marketing labels rather than descriptions. Underneath, every one of them is defined by the same three numbers: how wide the frame shell is, what the inside of that shell does, whether it is threaded or a smooth bore, and how big the crank spindle passing through it is. Get those three right and any bottom bracket fits.<\/p><p>This guide sets out every standard you are likely to meet on a road or gravel frame, groups them into the threaded and press-fit families, and shows you how to identify your own in about five minutes with a ruler.<\/p><p><a href=\"https:\/\/cyclingceramic.com\/wp-content\/uploads\/2026\/09\/CyclingCeramic-Articles-wheel-bearing-and-bottom-brackets-4.jpg\"><img decoding=\"async\" class=\"alignnone size-large wp-image-63414\" src=\"https:\/\/cyclingceramic.com\/wp-content\/uploads\/2026\/09\/CyclingCeramic-Articles-wheel-bearing-and-bottom-brackets-4-1024x1024.jpg\" alt=\"\" width=\"1024\" height=\"1024\" srcset=\"https:\/\/cyclingceramic.com\/wp-content\/uploads\/2026\/09\/CyclingCeramic-Articles-wheel-bearing-and-bottom-brackets-4-1024x1024.jpg 1024w, https:\/\/cyclingceramic.com\/wp-content\/uploads\/2026\/09\/CyclingCeramic-Articles-wheel-bearing-and-bottom-brackets-4-300x300.jpg 300w, https:\/\/cyclingceramic.com\/wp-content\/uploads\/2026\/09\/CyclingCeramic-Articles-wheel-bearing-and-bottom-brackets-4-150x150.jpg 150w, https:\/\/cyclingceramic.com\/wp-content\/uploads\/2026\/09\/CyclingCeramic-Articles-wheel-bearing-and-bottom-brackets-4-768x768.jpg 768w, https:\/\/cyclingceramic.com\/wp-content\/uploads\/2026\/09\/CyclingCeramic-Articles-wheel-bearing-and-bottom-brackets-4-1536x1536.jpg 1536w, https:\/\/cyclingceramic.com\/wp-content\/uploads\/2026\/09\/CyclingCeramic-Articles-wheel-bearing-and-bottom-brackets-4-12x12.jpg 12w, https:\/\/cyclingceramic.com\/wp-content\/uploads\/2026\/09\/CyclingCeramic-Articles-wheel-bearing-and-bottom-brackets-4-600x600.jpg 600w, https:\/\/cyclingceramic.com\/wp-content\/uploads\/2026\/09\/CyclingCeramic-Articles-wheel-bearing-and-bottom-brackets-4-100x100.jpg 100w, https:\/\/cyclingceramic.com\/wp-content\/uploads\/2026\/09\/CyclingCeramic-Articles-wheel-bearing-and-bottom-brackets-4.jpg 2048w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><\/a><\/p><\/section><section id=\"section-1\"><h2>The Three Numbers Behind Every Standard<\/h2><p><strong>Shell width.<\/strong> Measured across the bare frame shell with the bottom bracket removed. Common values are 68 mm and 73 mm on threaded frames, 79 mm, 82.5 mm, 85.5 mm, 86.5 mm and 92 mm on press-fit and wide threaded frames.<\/p><p><strong>Shell interface.<\/strong> Either a thread cut into the frame, which the cups screw into, or a smooth machined bore, which the cups or bearings press into. This single distinction splits every standard into the two families below, and it is the one that determines how the bottom bracket is installed and removed.<\/p><p><strong>Spindle diameter.<\/strong> The crankset decides this, not the frame. Four dominate the market: 24 mm on Shimano and most others, 24&#215;22 mm on SRAM GXP, 28.99 mm on SRAM DUB, and 30 mm on BB30-style cranks. A frame standard and a spindle standard are separate choices, which is why one shell type has several bottom brackets available for it.<\/p><div class=\"callout\"><strong>The mistake that causes most wrong orders.<\/strong> Riders identify their frame standard correctly and then forget the spindle. A BB86 frame is not one bottom bracket, it is four: one for 24 mm Shimano, one for 24&#215;22 mm SRAM GXP, one for 28.99 mm SRAM DUB and one for a 30 mm spindle. Both halves of the answer are needed before you buy.<\/div><\/section><section id=\"section-2\"><h2>Threaded Standards<\/h2><p>On a threaded frame, the cups screw directly into machined threads in the shell. The interface is mechanical, it can be tightened to a defined torque, and it can be removed and refitted repeatedly with standard tools.<\/p><table><thead><tr><th>Standard<\/th><th>Shell width<\/th><th>Thread<\/th><th>Notes<\/th><\/tr><\/thead><tbody><tr><td>BSA (English)<\/td><td>68 mm road, 73 mm MTB<\/td><td>1.37 in x 24 TPI<\/td><td>The oldest and most widely supported. Drive side is reverse threaded<\/td><\/tr><tr><td>ITA (Italian)<\/td><td>70 mm<\/td><td>36 mm x 24 TPI<\/td><td>Both sides conventional thread, mainly older Italian frames<\/td><\/tr><tr><td>T47 external cup<\/td><td>68 mm<\/td><td>M47 x 1 mm<\/td><td>Threaded shell with press-fit bearing diameter, external cups<\/td><\/tr><tr><td>T47 internal cup<\/td><td>85.5 or 86.5 mm<\/td><td>M47 x 1 mm<\/td><td>Bearings sit inside the shell. The industry has moved to 85.5 mm<\/td><\/tr><tr><td>T45 ThreadFit<\/td><td>82.5 mm<\/td><td>Frame-specific<\/td><td>Colnago ThreadFit 82.5 frames<\/td><\/tr><\/tbody><\/table><p>BSA is the reference point of the whole category. Its limitation is the bore: a 1.37 inch thread does not leave room for a 30 mm spindle with a serious bearing around it, which is what pushed the industry towards press-fit in the first place.<\/p><p>T47 is the answer the industry eventually settled on. It keeps the large 47 mm diameter that a 30 mm spindle needs, and threads it into the frame instead of pressing it. One detail to check before ordering: T47 internal cup exists in both 85.5 mm and 86.5 mm shell widths, since the industry standard moved from the second to the first, and Trek frames use the 85.5 mm figure.<\/p><\/section><section id=\"section-3\"><h2>Press-Fit Standards<\/h2><p>On a press-fit frame, there is no thread. Cups, or in some designs the bearings themselves, are pressed into a smooth machined bore and held by interference fit alone. That allows a larger bearing diameter and a lighter frame interface, and it makes the frame&#8217;s machining tolerance decisive.<\/p><table><thead><tr><th>Standard<\/th><th>Shell width<\/th><th>Bore<\/th><th>Notes<\/th><\/tr><\/thead><tbody><tr><td>BB86 \/ BB92<\/td><td>86.5 mm road, 92 mm MTB<\/td><td>41 mm<\/td><td>Narrow bore, designed around 24 mm spindles, pressed cups<\/td><\/tr><tr><td>BB30<\/td><td>68 mm road, 73 mm MTB<\/td><td>42 mm<\/td><td>Bearings press directly into the frame, no cups, 30 mm spindle<\/td><\/tr><tr><td>PF30<\/td><td>68 mm road, 73 mm MTB<\/td><td>46 mm<\/td><td>Same 30 mm spindle idea as BB30 but with pressed cups<\/td><\/tr><tr><td>PF30A<\/td><td>73 mm asymmetric<\/td><td>46 mm<\/td><td>Cannondale variant, the extra width added on the non-drive side<\/td><\/tr><tr><td>386EVO<\/td><td>86.5 mm<\/td><td>46 mm<\/td><td>Wide shell plus large bore, built for 30 mm spindles<\/td><\/tr><tr><td>BBRight<\/td><td>79 mm asymmetric<\/td><td>46 mm<\/td><td>Cerv\u00e9lo standard, extra width on the non-drive side<\/td><\/tr><tr><td>BB90 \/ BB95<\/td><td>90.5 mm, 95 mm MTB<\/td><td>Frame-specific<\/td><td>Trek, bearings pressed straight into the frame<\/td><\/tr><\/tbody><\/table><p>Two practical points come out of that table. First, bore size is the real dividing line, not the name: 41 mm shells are the 24 mm spindle family, and 46 mm shells are the 30 mm spindle family. Second, the wider the bore, the more a small machining error matters, which is why the 46 mm standards have the strongest association with creaking. The cause is tolerance in the frame and in the cups, not the ceramic or steel inside them.<\/p><p>A hybrid case is worth knowing about because it confuses a lot of orders: a 41 mm press-fit shell running a 30 mm spindle crankset. We list that combination as our 4130 bottom bracket, a BB86 shell fitted for a BB30 crank. If your frame is BB86 but your crankset is 30 mm, that is the unit you need, not a standard BB86 for Shimano.<\/p><p><a href=\"https:\/\/cyclingceramic.com\/wp-content\/uploads\/2026\/09\/CyclingCeramic-Articles-wheel-bearing-and-bottom-brackets-11.jpg\"><img decoding=\"async\" class=\"alignnone size-large wp-image-63421\" src=\"https:\/\/cyclingceramic.com\/wp-content\/uploads\/2026\/09\/CyclingCeramic-Articles-wheel-bearing-and-bottom-brackets-11-1024x683.jpg\" alt=\"\" width=\"1024\" height=\"683\" srcset=\"https:\/\/cyclingceramic.com\/wp-content\/uploads\/2026\/09\/CyclingCeramic-Articles-wheel-bearing-and-bottom-brackets-11-1024x683.jpg 1024w, https:\/\/cyclingceramic.com\/wp-content\/uploads\/2026\/09\/CyclingCeramic-Articles-wheel-bearing-and-bottom-brackets-11-300x200.jpg 300w, https:\/\/cyclingceramic.com\/wp-content\/uploads\/2026\/09\/CyclingCeramic-Articles-wheel-bearing-and-bottom-brackets-11-768x512.jpg 768w, https:\/\/cyclingceramic.com\/wp-content\/uploads\/2026\/09\/CyclingCeramic-Articles-wheel-bearing-and-bottom-brackets-11-1536x1024.jpg 1536w, https:\/\/cyclingceramic.com\/wp-content\/uploads\/2026\/09\/CyclingCeramic-Articles-wheel-bearing-and-bottom-brackets-11-18x12.jpg 18w, https:\/\/cyclingceramic.com\/wp-content\/uploads\/2026\/09\/CyclingCeramic-Articles-wheel-bearing-and-bottom-brackets-11-600x400.jpg 600w, https:\/\/cyclingceramic.com\/wp-content\/uploads\/2026\/09\/CyclingCeramic-Articles-wheel-bearing-and-bottom-brackets-11.jpg 2048w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><\/a><\/p><\/section><section id=\"section-4\"><h2>Identifying Your Own Standard in Five Minutes<\/h2><p>You need a ruler or a caliper, and the crank and bottom bracket out of the frame. Measuring over an installed bottom bracket gives you the wrong numbers every time.<\/p><p><strong>Step 1: measure the shell width<\/strong> across the bare frame, face to face. 68 mm, 70 mm, 73 mm, 79 mm, 82.5 mm, 85.5 mm, 86.5 mm, 90.5 mm or 92 mm.<\/p><p><strong>Step 2: look inside.<\/strong> Threads visible means BSA at 68 or 73 mm, Italian at 70 mm, or T47 if the thread is a fine M47 x 1 mm in a much larger opening. A smooth bore means press-fit, and you measure the inner diameter: 41 mm, 42 mm or 46 mm.<\/p><p><strong>Step 3: identify your crank spindle.<\/strong> Shimano and most others use 24 mm, SRAM GXP uses 24 mm on the drive side and 22 mm on the non-drive side, SRAM DUB uses 28.99 mm, and BB30-style cranks use 30 mm.<\/p><table><thead><tr><th>Width<\/th><th>Inside the shell<\/th><th>Standard<\/th><\/tr><\/thead><tbody><tr><td>68 mm<\/td><td>Threaded 1.37 in<\/td><td>BSA<\/td><\/tr><tr><td>70 mm<\/td><td>Threaded 36 mm<\/td><td>ITA<\/td><\/tr><tr><td>68 mm<\/td><td>Smooth 42 mm<\/td><td>BB30<\/td><\/tr><tr><td>68 mm<\/td><td>Smooth 46 mm<\/td><td>PF30<\/td><\/tr><tr><td>73 mm asymmetric<\/td><td>Smooth 46 mm<\/td><td>PF30A<\/td><\/tr><tr><td>79 mm<\/td><td>Smooth 46 mm<\/td><td>BBRight<\/td><\/tr><tr><td>86.5 mm<\/td><td>Smooth 41 mm<\/td><td>BB86<\/td><\/tr><tr><td>86.5 mm<\/td><td>Smooth 46 mm<\/td><td>386EVO<\/td><\/tr><tr><td>68 mm<\/td><td>Threaded M47<\/td><td>T47 external cup<\/td><\/tr><tr><td>85.5 or 86.5 mm<\/td><td>Threaded M47<\/td><td>T47 internal cup<\/td><\/tr><\/tbody><\/table><p>If the two measurements disagree with everything in the table, the frame is almost certainly using a brand-specific variant, and the frame manufacturer&#8217;s own documentation is the authority. Our <a href=\"\/bottom-bracket-compatibility-matrix\/\">bottom bracket compatibility matrix<\/a> resolves the frame standard and crankset combination directly, and the <a href=\"\/support\/bracket-for-bottom-brackets-cyclingceramic\/\">bottom bracket support page<\/a> covers fitting and torque once you have the right unit.<\/p><\/section><section id=\"section-5\"><h2>What Changes Once You Know Your Standard<\/h2><p>The standard determines fit. It does not determine how well the bottom bracket runs, and that is a separate decision made at the bearing.<\/p><p>Every standard in this guide is available with hybrid ceramic internals, and the friction difference has been measured independently. Friction Facts tested a CyclingCeramic bottom bracket at 0.56W against 1.57W for a standard Shimano Dura-Ace BB86 unit.<\/p><table><thead><tr><th>Bottom bracket<\/th><th>Measured friction<\/th><th>Difference<\/th><\/tr><\/thead><tbody><tr><td>Shimano Dura-Ace BB86 standard<\/td><td>1.57W<\/td><td>Baseline<\/td><\/tr><tr><td>CyclingCeramic<\/td><td class=\"green\">0.56W<\/td><td class=\"green\">-1.01W (64%)<\/td><\/tr><\/tbody><\/table><p>We cover BSA, ITA, BB86, BB30, PF30 and PF30A, 386EVO, BBRight, BB90, T47 in external and internal cup versions, T47A, T45 ThreadFit, 4130, and the Campagnolo Ultra Torque, Over Torque and Look BB65 crank systems, each in the spindle diameters that standard accepts. If your frame standard is on that list, the fit question is solved and the only remaining decision is what runs inside it. For the full argument on whether ceramic is worth it in this specific component, our <a href=\"\/ceramic-bottom-bracket-vs-standard\/\">ceramic bottom bracket versus standard comparison<\/a> has the lab data and the honest caveats.<\/p><p>One thing the standard does affect is how the bottom bracket is installed, and that has real consequences for creaking and service life. That comparison has its own guide: <a href=\"\/threaded-vs-press-fit-bottom-bracket\/\">threaded versus press-fit bottom brackets<\/a>.<\/p><\/section><section id=\"section-faq\" class=\"faq-section\"><h2>Frequently Asked Questions<\/h2><div><h3>How many bottom bracket types are there?<\/h3><div><p>There is no fixed count, because frame brands keep adding variants, but around a dozen standards cover almost every road and gravel bike in use. The threaded family includes BSA English, Italian ITA, T47 in its external and internal cup versions, and frame-specific threaded types such as the T45 ThreadFit used by Colnago. The press-fit family includes BB86 and BB92, BB30, PF30 and the asymmetric PF30A, 386EVO, BBRight, and direct-press frame standards such as Trek BB90. Each one is defined by shell width, shell bore or thread, and the crank spindle it accepts.<\/p><\/div><\/div><div><h3>How do I know which bottom bracket type my frame uses?<\/h3><div><p>Measure two things with the crank and bottom bracket removed: the width of the bare shell and its inner diameter or thread. A 68 mm shell with visible threads is BSA, 70 mm threaded is Italian, 86.5 mm with a smooth 41 mm bore is BB86, 68 mm with a smooth 46 mm bore is PF30, 68 mm with a smooth 42 mm bore is BB30, and 86.5 mm with a 46 mm bore is 386EVO. Then check what spindle your crankset uses, since the same shell accepts different bottom brackets for a 24 mm Shimano, 24&#215;22 mm SRAM GXP, 28.99 mm SRAM DUB or 30 mm spindle.<\/p><\/div><\/div><div><h3>What is the difference between BB86 and PF30?<\/h3><div><p>Both are press-fit, but they are built around different spindle sizes. BB86 has a narrow 41 mm bore in an 86.5 mm wide shell and was designed around 24 mm Shimano-style spindles, with the bearings sitting inside small pressed cups. PF30 has a much larger 46 mm bore in a 68 mm shell and was designed around 30 mm spindles, which are lighter and stiffer for the same weight of material. The wider bore is also why PF30 is more sensitive to frame tolerance, since a larger diameter magnifies any error in roundness.<\/p><\/div><\/div><div><h3>Is T47 better than BSA?<\/h3><div><p>T47 keeps the large bearing diameter of press-fit designs while threading into the frame like BSA, so it accepts 30 mm spindles that a 1.37 inch BSA shell cannot easily take, and it can be installed and removed with normal shop tools. BSA remains the simplest and most widely supported standard, with parts available everywhere. Neither is universally better, and in practice you do not choose: the frame decides. What both share is that a threaded interface can be tightened to a defined torque, which is why serviceability is generally easier on both than on a pressed interface.<\/p><\/div><\/div><div><h3>Can I convert my bottom bracket to a different standard?<\/h3><div><p>You cannot change the frame shell itself, but you can often change which crankset it accepts, and that is what most riders actually need. A single shell standard is covered by several bottom brackets, one per spindle diameter, so a BB86 frame can run a 24 mm Shimano crank, a 24&#215;22 mm SRAM GXP crank, a 28.99 mm DUB crank or, with the right unit, a 30 mm spindle crank. Converting between shell standards, such as a press-fit shell to a threaded interface, requires a dedicated conversion kit and is a workshop job.<\/p><\/div><\/div><\/section><section id=\"section-conclusion\"><h2>Bottom Line<\/h2><p>Bottom bracket standards are not as complicated as the naming suggests. Measure the shell width, look inside for a thread or a smooth bore, measure that bore, then identify your crank spindle. Those three answers name your standard and select your part, and no amount of brand terminology changes them.<\/p><p>Once the fit is settled, the only variable left is what runs inside the shell, where an independently measured 64% friction reduction is available in every standard. For threaded frames, that means a <a href=\"\/shop\/bottom-bracket-bsa-shimano\/\">BSA unit<\/a>, an <a href=\"\/shop\/bottom-bracket-ita-shimano\/\">Italian unit<\/a> or a <a href=\"\/shop\/bottom-bracket-t47-86-shimano\/\">T47 internal cup unit<\/a>. For press-fit frames, a <a href=\"\/shop\/bottom-bracket-bb86-shimano\/\">BB86<\/a> or <a href=\"\/shop\/pf30-shimano\/\">PF30<\/a> unit in the right spindle diameter. All are handmade in France on Grade 3 Si3N4 balls with a 4-year warranty. If you are unsure which line matches your frame, the <a href=\"\/bottom-bracket-compatibility-matrix\/\">compatibility matrix<\/a> answers it in two clicks.<\/p><\/section><\/article>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t","protected":false},"excerpt":{"rendered":"<p>Bottom bracket standards look chaotic because the names are marketing labels rather than descriptions. Underneath, every one of them is [&hellip;]<\/p>\n","protected":false},"author":1939,"featured_media":63422,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"wpai_generated_summary":"","footnotes":""},"categories":[1479,264],"tags":[],"class_list":["post-63299","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-guide","category-workshop"],"acf":[],"_links":{"self":[{"href":"https:\/\/cyclingceramic.com\/es\/wp-json\/wp\/v2\/posts\/63299","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/cyclingceramic.com\/es\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/cyclingceramic.com\/es\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/cyclingceramic.com\/es\/wp-json\/wp\/v2\/users\/1939"}],"replies":[{"embeddable":true,"href":"https:\/\/cyclingceramic.com\/es\/wp-json\/wp\/v2\/comments?post=63299"}],"version-history":[{"count":3,"href":"https:\/\/cyclingceramic.com\/es\/wp-json\/wp\/v2\/posts\/63299\/revisions"}],"predecessor-version":[{"id":63435,"href":"https:\/\/cyclingceramic.com\/es\/wp-json\/wp\/v2\/posts\/63299\/revisions\/63435"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/cyclingceramic.com\/es\/wp-json\/wp\/v2\/media\/63422"}],"wp:attachment":[{"href":"https:\/\/cyclingceramic.com\/es\/wp-json\/wp\/v2\/media?parent=63299"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cyclingceramic.com\/es\/wp-json\/wp\/v2\/categories?post=63299"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cyclingceramic.com\/es\/wp-json\/wp\/v2\/tags?post=63299"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}