You are reading a single comment by @bashthebox and its replies.
Click here to read the full conversation.
London Fixed Gear and Single-Speed is a community of predominantly fixed gear and single-speed cyclists in and around London, UK.
This site is supported almost exclusively by donations. Please consider donating a small amount regularly.
bashthebox
The rear dérailleur travel is the same for 8, 9 and 10 speed (they just squeeze more sprockets into the same width by narrowing the chain), so you can use an 8 or 9 speed RD on a 10-speed cassette. In fact, you can probably get away with a 6 or 7 speed RD too, as they had only about 3mm less travel and there was always some wiggle room to allow for dropout geometry variation, hence the limit screws. Potentially, using a lower speed RD makes shifting slower/less precise as the cage plates get progressively further apart as you drop down the speed range, but it only really gets bad if there is a large mismatch.