Ohama is not my game so if there is a flaw in my logic, please point it out.

You have 16 outs. You are 33% to catch the straight and win the pot, although maybe just a share of it. The pot is just right making it a coin toss.

A flush draw is on the board meaning some of your outs may be gone. Do you assume he has two spades and take away 5 outs or figure he has a 1 in 4 chance of being on a spade draw effectively taking away one out. Either way you are no longer getting pot odds.

What about implied odds? If you hit the straight will you get paid off? Probably not if he is an experienced vet. You left out seat position. If you are first to act and bet he will probably fold. If you check he will probably check. If you are second to act and bet he may call if he thinks you are bluffing.

What could your opponent have? He raised preflop. I put him on highs cards with straight and/or flush possibilities. Since he may be drawing to one of the same straights I am that greatly reduces my return.

I fold.

PS Don't you have just 670 left?