8-speed chain on a 9-speed
So I converted my tour bike's 8 speed drivetrain to a 9 speed and kept my 8-speed Sram PC58 chain and the thing indexes and runs flawlessly. I thought you needed a narrower 9-speed chain. Must I use a 9-speed chain? Or am I playing with very tight tolerances here by using an 8-speed chain? Thanks.