While it's probably technically possible,

  1. it's likely not worth the money to, as even a budget fork can easily cost $100-200 on its own, and cheaper ones often have poor rebound that just kind of kicks you back like a pogo stick instead of just absorbing bumps
  2. may not be advisable anyway as I doubt the frame was designed around it

The head tube angle is a fairly steep 71°, and when suspension compresses the nose dives down a bit to make it even steeper, so it could have a tendency to feel like it's trying to throw you over the bars under sudden stopping or unexpected obstacle. A suspension fork also is necessarily longer to allow for wheel clearance throughout the travel, so it's going to push the front end higher as well. I'm not a professional mechanic though, so might be best to consult a shop, or if any REI techs want to jump in this thread to weigh in. You'd only get a small amount of travel at best though.

Another option you could try looking at is there are some suspension seatposts out there that could take the edge off of bigger jolts.

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