5 steps to replacing chainrings. New and old drivetrains. Bike Service School. Lesson 9. скачать в хорошем качестве

5 steps to replacing chainrings. New and old drivetrains. Bike Service School. Lesson 9.

0:00 drivetrain problems 0:51 1. teeth number 3:31 2. chainring mount 7:41 3. chainline / offset 8:54 3 mm boost offset 9:50 chainline measurement 10:55 O.L.D. explained 13:57 4. chainring model 14:31 dremel hack 16:10 5. Shimano 12s only 17:27 YOUR TEST B.C.D. Bolt Circle Diameter = P.C.D. Pitch Circle Diameter How to calculate B.C.D.: 5 bolt chainring A x 1.701 = B.C.D. ("A" is center-to-center dimension between bolt) EXAMPLE 64.7 mm x 1.701 = 110 mm B.C.D. 3 bolt chainring A x 1.155 = B.C.D. Where to buy: Shimano 12 speed chainrings https://amzn.to/3L1UWZ7 Sram 12 speed Boost chainring https://amzn.to/4c0bFYk Sram 12 speed 6 mm non - Boost offset https://amzn.to/3XEOI95 Shimano 12 speed Deore cranksets https://amzn.to/3z31cwP