Bicycle Components & Parts

51Tooth Chainring 86mm BCD SR Stronglight NOS https://www.sheldonbrown.com/cribsheet-bcd.html 4-Bolt Cranks/Chainwheels, even spacing: For uneven spacings, see the next section of this table. Beware of near-matches! Measure! The BCD is 1.414, 1/sin 45°, times the spacing between adjacent holes. BCD (mm) Smallest Ring Between adjacent holes (mm) Application 146 44 103.2 Shimano XTR M960 Hollowtech 4-arm outer. 120 36 84.9 SRAM 2 x 10 and XX. Threaded. 112 34 79.2 Shimano XTR M950, M952 4-arm middle/outer 110 34 77.8 FSA K-Force Light, Vero Pro 104 30 73.5 Shimano XT, LX 4-arm outer 12 SPD, Sugino MX350. Some are threaded. See RaceFace compatibility table. 102 32 72.1 Shimano 2003 XTR MX960 4-arm middle, 96 30 67.9 Shimano compact triple cranksets models M782, M672, M622, M612 94 30 66.5 SRAM XO1, X1, GX, NX 90 30 63.6 FSA: K-Force Modular Supercompact, Omega Pro, Powerbox Supercompact Stealth, Road Modular, Vero Pro 88 28 62.2 Shimano M985 68 22 48.1 Shimano XTR M950, M952 4-arm inner, FSA Comet Modular 64 22 45.3 Shimano XTR M960, XT, LX 4-arm inner. See RaceFace compatibility table. 58 20 41.0 Sugino MX350 4-arm inner 4-Bolt Cranks/Chainwheels, uneven spacing: Measurements between adjacent holes of uneven patterns are adjusted to nearest whole degree of angle between bolt holes, reflecting probable correct values. The first number given is for holes either side of the crank. If there are three spacings, the last and smallest is for holes opposite the crank. BCD (mm) Smallest Ring Between adjacent holes (mm) Application 145 44 111.1, 93.2 Campagnolo Super Record, Record, Chorus 2015- outer 112 34 85.8, 72.0 Campagnolo Super Record, Record, Chorus 2015- inner 110 34 90.1, 63.1 Shimano Dura Ace 9000, Ultegra 6800, 105 5800, Tiagra 4703, 4700; Dura Ace with modification 110 34 89.0, 64.7 SRAM Apex 1. 72/108 degree angles. Shimano is 70, 110 degrees. 110 34 84.3, 77.8, 70.7 FSA Gossamer ABS, K-Force ABS, Powerbox, SL-K ABS 100 32 92.7, 64.3, 58.8 3T Torno. Must use 3T bolts. Looks like a 5-bolt pattern with one bolt missing. 96 30 78.6, 55.1 Shimano XT M8000, SLX M7000, Deore M6000, 10mm holes; XTR M9000 and M9020, M7 threaded holes. 96 36 73.5, 67.9, 61.7 FSA 96/68 SLK MTB ABS 76 26 65.8, 48.9 FSA Afterburner, Comet, K-Korce, SLK MTB ABS 76 25 62.3, 53.7, 48.9 SRAM XX1 11-speed, Cannondale, Specialized Stout. Threaded for M8 bolts. 68 22 52.1, 48.1, 43.7 FSA Comet MTB Modular, Comet triple, K-Force Modular, SL-K MTB Modular, V-Drive MTB Modular 64 22 52.4, 36.7 Shimano XT, SLX, XTR 11-speed with the "X" shaped bolt pattern. 5-Bolt Cranks/Chainwheels: The BCD is: 1.701, 1/sin 36°, times the spacing between adjacent holes, 1.052 , 1/sin 72°, times the spacing between non-adjacent holes. BCD (mm) Smallest Ring Between adjacent holes (mm) Between non-adjacent holes (mm) Application 151 44 88.8 143.6 Very old Campagnolo standard (pre '67) (Obsolete) 144 41 84.6 137.0 Old Campagnolo standard, still used for track; Sturmey-Archer FCT 135 39 79.4 128.4 Current Campagnolo standard 130 38 76.4 123.6 Standard Road double and triple (outer 2); Sturmey-Archer FCS 128 38 75.2 121.7 Nervar Sport, Star (Obsolete) 122 38 71.7 116.0 Stronglight 93, 101, 103, 104, 105 (Obsolete) 118 36 69.4 112.2 Ofmega, SR (Obsolete) 116 35 68.2 110.3 Old Campagnolo Gran Sport touring, Victory, Triomphe 110, 112 34 64.7, 65.2 104.6, 105.6 Campagnolo CT inner/middle/outer with one bolt at larger diameter behind crank 110 38 77.8, 70.7, 46.5 FSA K-Force ABS: uneven pattern, 4 bolt with extra bolt behind crank 110 33 64.7 104.6 Touring double, standard triple outer 102 32 60.0 97.0 Avocet triple inner (obsolete). Note, NOT same as Campagnolo. 100 31; 36 58.8 95.1 Merz adapter; Campagnolo triple inner (Obsolete) 94 29 55.3 89.4 Compact triple outer 93 28 58.5, 52.7, 55.3, 54.0, 52.7 Wolf Tooth "CAMO", barely noticeable uneven spacing, requires Wolf Tooth spider and bolts. 92 30 54.1 87.5 Shimano Dura-Ace triple inner 90 30 52.9 85.6 Edco, Mavic triple inner (old) 86 28 50.5 81.8 Stronglight 80, 99, 100, SR Apex (Obsolete). Chainwheels must be installed back to back, triple shifts poorly. 85 28 50.0 80.8 Old Shimano Deore, Takagi triple inner. (Obsolete) 80 26 47.0 76.1 Tevano (TA Campagnolo clone) triple inner. Bolts not interchangeable with others. 74 24 43.5 70.4 Standard ("full-sized") triple inner, used with 110 mm, 130 mm or 135 mm outer. 58 20 34.1 55.2 Compact granny 56 20 32.9 53.3 Sun Tour Compact granny (Obsolete) 50.4 n/a 29.6 47.9 TA Cyclotouriste, Criterium, Lambert, Shimano Deore, others: attachment for outer chainring; 7 mm holes. 6- and 3-Bolt Cranks/Chainwheels: The BCD is: 2.000, 1/sin 30°, times the spacing between adjacent holes (6-bolt), 1.154 , 1/sin 60°, times the spacing between adjacent holes (3-bolt) or non-adjacent holes (6 bolt) BCD (mm) Smallest Ring Between holes 60° apart (mm), 6-bolt Between holes 120° apart (mm) Application 157 78.5 136.0 Several very old Euro models 152 43 76 131.6 TA Criterium bolts between outer chainwheel and others. 143 42 71.5 123.8 Lambert. Inner ring threaded. 140 40 121.2 Campagnolo Gran Sport inner 116 36 100.4 TA Professional (10 mm holes), many old Euro steel cranks 116 36 58 100.4 TA Randonneur: bolts are between outer chainwheel and others. 112 ? 97.0 Takagi 106 32 91.8 Sugino Maxy, others w/8mm holes, SR Apex w/10mm holes. 95 30 82.3 Shimano 600, 310 88.9 (3.5") 30? 77.0 Nicklin, Cross, Williams (very old) 86 28 74.5 FSA Pro MTB 386, Comet 386 MTB 85 28 73.6 SR Custom 3 80 26 40 69.2 TA Cyclotouriste, Lambert: bolts between outer chainwheel and others. 70 24 60.6 René Herse. 10mm holes.