I definitely agree with the question of IFI releasing them early, but there obviously is some market interest with the different sized wheels. I have to disagree with the argument of increased costs causing FIRST not to include them. Exhibit A: The kit bot itself. The material in the frame itself has over 1000 square inches of 1/8 aluminum in it, whereas a 6" wheel probably has like 100 square inches of 1/8. so, with two wheels included, that less than 1/5 of the kit bot material. They could probably use scraps!
That notwithstanding, they probably don't actually cost 30 bucks to make ( I know you were just using an example...but I'm in a number mood.) At a high price, which IFI probably won't have in bulk, 1/8" aluminum costs like 9.7 cents a square inch. .097*100=$9.70. Add in 7 dollars for two good 1/2" bearings, and the total is 15.70. I don't know how much wedgetop costs, but lets say 3 bucks to cover a wheel. Add in a bit of hardware and we're still only at 20 bucks. Thats as much as we paid for a spare side rail.
So, assuming IFI only gives us two, with two skyways in front, thats 40 bucks added onto the cost, minus whatever the skyway's cost FIRST. Sounds like a good deal to me for what you would get out of it by helping teams out!

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