It's getting fuel; has spark. Will work on some others.
Two things come to mind, both fuel (not spark) related:
1. Choke: The VKA has an autochoke that responds to heat (or a lack of it). If the autochoke is not working properly, it could be staying stuck closed when it should be open. This would result in a too rich condition and causing problems. To check: (a) engine must be completely cold. (b) inspect choke plate; it should be closed. (c) gently force it open with small screwdriver; the spring should make it close again. (d) If not, check the springs and make sure they are all connected properly. Next, you can further confirm the choke is working by (a) Start and run the engine at full throttle for 3 full minutes. (b) shut it down, wait a full 20 minutes. (c) Check the choke again, and it should be fully closed.
2. Debris in the Carb: <sigh> I have personally struggled with this demon on my HRX twice this season already. Even the *smallest* bit of gunk can cause poor running or no running conditions. First time, I tried cleaning the carb, and never could get it to start. Second time, mower was surging and would not idle. Cleaned the carb okay, and now all good. My point? Well, if all else fails on a poor running engine, and spark is good,
replace the carb. I say this only 'cause you can spend
hours trying to fix one, or a little $ for a whole new one that bolts right on. FYI, "debris in the carb" is not a factory defect, so no warranty. The list price on a new carb is only $18.21, and I'd go ahead and replace the gaskets too; here's a shot from the parts catalog; red arrows point to the carb for your mower and suggested gaskets to replace. Any Honda dealer can get you these parts.
Caveat #1: Actual retail prices of parts are set at the sole discretion of the individual Honda dealer.
