i dunno, camlifter, i don't see a problem with clutches burning up, or really anything for that matter.
i mean, it'd be smart to bring along spare parts, especially chains, tubes and tires, and a whole 'nother complete motor, just in case, but my experience with my bikes shows i'm not gonna burn out a clutch in one day of racing.
i run my bikes full throttle all day long, flat out downhills, uphills, and in some areas where there's not a stop sign for miles.
i don't think any parts would "wear out." if something was gonna break, most likely it'd be a defective part or a flat tire.
i want to bring the bike i'm building now down there, and by then it'll probably have a thousand miles or more on it. i think once the bike's built, it should be broken in, and ridden hard before it hits the salt, just to work out all the kinks.
depending on the rules, i might hop-up a 50cc china motor, but i figure if i can't set an official record with either motor, i'll stick with the 66 for more speed.