Review on 🚴 Funn Zippa Lite MTB Chain Guide Review: ISCG05 Mount, 26T-36T, Bicycle Chain Protector by Yung Kaelin

Over the years we have installed and run chain guides from E13, MRP, Specialized, Race Fave and more to fit a variety of chainrings without the 50T 12 speed cog to scrub. I installed this 8/21 on a 2016 Stumpjumper with a 1x12 Sram GX drivetrain. A stuck rear derailleur was preventing the chain from falling off on its own until my son started rattling a lot more and fell off from time to time. With the FUNN guide installed, it hasn't crashed again and we've got about 150 miles and a few days of DH and bike park jumps (NorthStar) behind us. Works very well. It turns out that this year's carbon Stumpjumpers actually have trouble mounting most stock ISCG05 guides, due to the raised "bottom bracket" lip protruding too close to the guide face. The solution requires 1.5mm shin washers behind the rail to mount flush. It's a solid solution and there is still a lot of tweaking to do to center the guide over the chainring...but at first I was really frustrated that it just didn't fit. In short, this is actually a specific problem that everyone but these chain guides have on this frame.