This was my world for a long time...I still have 20 baitcasting rods and reels. IMO the type of rod and reel is WAY more important than the brand. A top-notch rod/reel used for the wrong application is the same as having crappy gear.
A crankbait rod isn't going to handle spinnerbaits very well. Also, the ideal reel for crank bait fishing will have a different gear ratio than the ideal gear ratio you would want for spinner baits.
A good crankbait rod should be a slower action rod with a bigger parabolic bend or curve. Crankbaits put a lot of bend in a rod and the way fish eat a crankbait makes it necessary for the rod to be forgiving on the strike, so you don't rip those trebles through the fish's mouth. Lots of guys prefer glass over graphite for that reason.
When it comes to a reel, I always liked a 5.3:1 gear ratio for cranking. Crank baits need to be retrieved a little slower than a spinner bait and a slower geared reel allows you to turn the crank at the same speed as you would a 6.4:1 or 7.3:1 reel while getting the desired retrieval speed. The right crank bait rod could serve as a rattle trap rod as well a swim jig rod.
A spinner bait rod should be a heavier rod and faster action. The ideal reel will be a 6.4:1 or 7.3:1 reel. Spinner baits will be fished more around heavy cover and their giant hook doesn't pull out like a smaller treble will. A spinner bait is also going to be heavier than a crank bait, most of the time, so a heavier rod with a faster action is better for casting.
When you get a spinner bait bite, often times you need to move that fish away from cover fast which will require a powerful rod and a reel that can pick up line fast. In addition, most of the time you are retrieving a spinner bait at a faster pace than a crank bait, so a faster reel is better.
A good spinner bait set up can double as a jig rod, texas rig pitching rod and in some cases a decent buzz bait, spook, or other top water bait rod.
Be careful...its' pretty easy to end up with 40 rods/reels and find yourself in a tournament circuit one day.... it's a slippery slope and hard to recover from
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