I have a 7'4" MH, Moderate rod and am wondering if that is too flimsy for bing used as a topwater (walking baits) rod. Thanks

I'd consider it to be a bit stiff for topwaters, unless you plan on using it for tossing frogs on pads. But thats me, I prefer a med action for topwaters

Not necessarily , It really depends on the rod I have a mhm rod that works fine for top water.

I have one that I use for rats and things alike

Super spooks, 5" lunker punkers, buzzjets.   All could be used on that rod.

I would use a rod with a little faster action for topwater.   Moderate action rods have more give in them than I like when working the bait.  It may be a matter of preference but when I want to put some action on the bait I do not want half the rod flexing.    The other side of the coin is that the moderate action rod will help keep a fish pinned better.  I typically use fast action rods with a soft tip for my topwater baits, power is dependent on the weight of the bait and conditions I am fishing in.

U mention walkn dog, 7'4 is to long unless u r 6'6 or taller.

26 minutes ago, chadmack282 said:

U mention walkn dog, 7'4 is to long unless u r 6'6 or taller.

 

Totally can walk a bait with a long rod, just don't go straight down with your movement, go diagonally down to the side.

A good all around length for twitch baits , Sammy's , Gunfish , etc. would be a 6'6" M Fast used with #20 to #30 lb. braid or #12 to #17 lb. mono .

 

I went looking for a topwater rod once.  But I couldn't find one that floats.

Depending on the manufacturer those specs should be good for bigger sammies and spooks, though I usually stick with a 6'6" or 7' for those techniques . Ive founder softer action rods can be sped a bit up with braid. You're wrists dont have to fight a stretchy line like mono to walk the dog, but you still have some give in the rod to keep a fish pinned. That rod with mono = alot of stretch and inertia to move the bait. As someone whos dang near got carpal tunnel from topwater baits, braid helps with the torque on the wrists on long casts.

I don't currently use this rod for topwater, its my spinnerbait/ soft plastic swimbait/ crankin' rod. I don't have the funds to buy one rod for every application and am trying to narrow my future arsenal down to 4 bait casters and one spinning rod for all techniques that I use most. I have this MH Mod rod and always heard that for topwater you are supposed to use a lighter rod so i thought that this possibly could be my topwater rod. I would be mostly throwing spooks (both jr and regular)  and  whopper ploppers.

I think it would be fine as long as you'll be fine with the length. If you can't impart enough action using mono try a braid. 

I like a med mod/fast for 1/2 ounce walking baits, then step it up to a MH fast for 3/4 and up. If you need more stiffness use braid, if you want more flexibility use mono. 

Don't read too deep into what anyone tells you. Get out and fish what you've got and you'll decide what you think is appropriate for you.

90% of the time I fish from a kayak so I have to walk the dog with the rod parallel to the water. Rod length is not a problem, at least for me.