Honda self-propelled hard to pull backwards

[VegetiveSteam]

Hopefully someone has a solution for this issue. I inherited a Honda self-propelled walk behind mower, model HRR216K10VKAA. serial MZCG-1342918. The self-propelled works fine. The issue is, in the grass, the drive wheels simply slide on the grass when you pull the mower backward. They won't roll backward. They will roll on concrete but with some difficulty. If it matters, it makes no difference whether or not the engine is running. It seems to be a nice mower overall, but I can't believe Honda would build a mower that would end up being so hard to use. Do any of you know of a fix for this issue? I appreciate any help. Thanks.

 

[Auto Doc's]

Sounds like self-propel cable adjustment issue. The cable is possibly a little too tight. Another possibility is the drive belt has been replaced, and it does have enough slack when not in drive mode.