OldKD, not all of that is entirely true!
"1. You will wreck your engine."
Why would you assume that an engine that is guaranteed by the manufacturer to run 50hrs could not cope with a 2.5, 6, or even indeed 24 hrs? You just up the oil/fuel ratio to help engine run longer, use different plug, jetting, etc.
"2. You will wreck your tyres."
Don't you? You are indeed right in assuming the SL8's or SL6's would not last more than about 100laps, but then Rotax's are used in endurance and they do use harder compound tyres to last the race. It's like cracking a nut, you wouldn't use a sledgehammer to do the job of a nut cracker would you?
"3. You will wreck your body."
Is the track any different if you drive a 2T from a 4T kart? What's one thing got to do with the other? Since when you have to go "slower" to last an endurance race? You think that the 24hr Le-Mans cars are going slower than they would if they were doing a sprint race? Flat out they go!
"4. You will probably use up all your pocket money and your parents will need a second mortgage to pay to put it all right."
Now here's where you're getting closer to the truth, although the only extra spending is in the engine rebuilds!
"It would be cheaper to dump your kart and buy a new one."
Once again, you wouldn't use a supple sprint chassis for an endurance race! Refer you back to the nut and the sledgehammer!
All in all thanks for the compliments though, finally a Prokart driver that has been man enough to admit that the real racing is to be had in a 2T machine! Thanks OldKD!
All that aside you are right, there are less Rotax endurance races than Prokart and they never race together in the same class. The Prokarts are indeed just made for the endurance!
To the extent that other than Llandow and IOM there aren't many other clubs that have a regular sprint class on the race calendar! I haven't come across any in my travels yet!
To end it all have a look at this website:
http://www.openendurancechampionship.co.uk/oekc02.htm
Dan
PS. Not sure if you are aware that a British team has this summer set a new record at distance travelled in a kart during 24hrs. It was done in a 2T gearbox kart, they used 3-4 engines and 4 drivers. Prokarts were used only to retrieve the machine back to pits when it ceased or broke down!