how long of a race and what type of sand? for a long up say around >100m, 21'' 8 paddle on an 8" rim. the tire has more of a balloon shape and will float better on loose sand and 8 paddles from my experience with numerous hill shooter bikes will work will for approx 55-70ish whp for that distance. for a short run on more paddle will help with the launch and since the run is short the extra paddles will not hold you back like they do on a longer race. once the atv is rolling too many paddles will slow you down. from practicing numerous time with launches and watching personal videos i made the you have a large wheel and lower profile tire the tire tends to sink in the sand on a hard launch before it grabs vs a balloon tire that slowly crawls before it grips. on hard packed sand you can get away a lower profile tire and if its a short run, more paddle will get you going sooner provide you can control your launch and not wheelie over, a long swinger helps. the extreme has the same size paddle as the standard hauler just a thicker base so they do not damage as easily if you rider over hard packed dirt on the way to the sand.