When it all boils down Joe, if you aren't fanging it up & down your driveway all the time, you probably stand no more chance of causing a belt or tire issue on your Spyder due to the gravel on the driveway than you do from 'normal' road use!! :dontknow:
In fact, by ryding gently & trying not to spin the drive tire or slide the steer tires as you go up & down your driveway, you probably stand somewhat
less chance of copping belt or tire damage than every single ryder in Aust faces pretty much every time they ryde
anywhere outside the CBD's of our big cities!! And there's a
whole lot of us here who do tens of thousands of miles annually on our 'non city' roads; many of us daily driving/ryding on roads that barely qualify as being called 'sealed', but we rarely hear of or experience belt or tire issues!!

I often wonder how many have
actually ever had any belt issues?!? (maybe someone should do a poll? Interested PMK?)
Yes, there's a chance of something bad happening whenever you ride... in your case, maybe a
very slightly higher chance of belt damage than for those ryders who never leave the blacktop; but realistically, you probably stand significantly more chance of falling over & breaking something while climbing on/off your Spyder than you do of damaging a tire or belt thru ryding carefully on the gravel driveway! Sure, it won't hurt you to minimise the risk by taking care, keeping your tires at appropriate pressures (going too high increases the risk of puncture exponentially, while going too low risks sidewall damage) &/or maybe even making up a belt guard yourself - but seriously, the best thing you could do for yourself is:
Ride More & Worry Less! :thumbup: