Originally Posted by
SoSmellyAir
Why not? I am just curious, not trying to be argumentative. The two 1X specific features which I have read the most about: (1) a chain ring with alternating narrow and wide teeth; and (b) a rear derailleur with a clutch and/or damper, are designed to reduce the possibility of dropping the chain on bumpy cyclocross / gravel rides. If the OP does not ride on very bumpy surfaces, then a chain guide (e.g., as shown in my 1X conversion thread) may be sufficient, right?
1x also usually means a very wide range cassette. As 1x was catching on in popularity a few years ago, it became popular to pair a large cassette (>40t) with a 10sp derailleur with a rated capacity of 36t max, possibly with a longer b tension screw or a wolftooth link. This was/is a pretty good option to modify an existing bike to 1x. It works, usually okay, but it is definitely worse than a derailleur intended for a wide range cassette.
Given the pretty low cost of 1x drivetrains these days, I'm just recommending against hacking a wide range 10sp cassette with a clutched Sram or Shimano derailleur not rated for that size of you're buying new parts anyways—its just a poor value.
If you want a simple, city bike 1x setup with, say, a 9 sp 11-36, a narrow wide chainring and possibly a chain guide, it'll work totally fine with an inexpensive, nonclutched derailleur rated for that size (or reasonable close to it. )