comments:
I build my own Hardtail using a NS Surge Evo frame along with a 750W BBS02, I take it out on single track and fairly technical trails and haven't had issues like this. I came up with my own mix and match groupset, a Deore RD-M5100 derailluer, 11-48T Microshift Advent MX 10-speed cassette, and a Shimano Saint SL-M820 shifter. It shifts super fast and smooth as silk, the Deore RD has a clutch for chain retention, plus it's fairly durable and is tucked in tightly next to the frame. The Saint shifter has "instant release" allowing me to shift multiple gears in the split second that the shift sensor cuts power, and the MX cassette is made from Chromoly steel which helps prevent wear with so much power thru the drive train. I am not sure why you keep trashing derailleurs, I could see that happening in certain rare circumstances, but not as frequently as you are experiencing. It could just be because those Tourney derailleurs are fairly flimsy and sit further out from the frame and in the path of trail debris. They do make rear derailleur bash guards that bolt onto the rack mount holes near the drop outs. Might be worth trying if your frame supports it. Or invest in a proper MTB groupset designed to handle the abuse of riding on trails.