Essential Gear

The wetsuit question/answer will depend on the water temperature for your race(s). 

Tri-specific clothing is almost a must for racing (yes I realize some use other pieces but in general tri specific clothing is preferred) - that could be a one-piece tri suit OR a tri short/top combination. Really an individual preference on that one.

If you're considering wearing a SCUBA or surfing wetsuit for a race, I wouldn't recommend it.  As I understand it they have significant design differences from one designed for swimming.  That said, you may or not actually need a wetsuit depending on your race.

A tri suit or tri top/tri shorts is basically a must for racing.

Easy to answer, but to get a good answer, we really need expected air temps, water temps, and distances for your first few prospective races.

The answer is easy really, get a cool set of Oakley's so you look good.  

OK, from an essentials standpoint assuming the water temp is ok sans wetsuit the only thing I'd say you "need" is a pair of tri shorts.  You'll see many guys do the swim/bike with just shorts on and throw a T-shirt on for the run.

If you want a top too then it's a personal preference thing as far as a Tri Suit versus a Tri Top.  I bought a Tri Suit last year and will be going 2 piece this year because it was a royal pain to go to the restroom in the Tri suit.

Hahaha!

Your surfing wetsuit should work just fine for your first race or two... or three or more... If you decide you really like triathlons, then look into a tri-specific wetsuit. For starters? Tri shorts.

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