Alloy or steel basket, sintered or organic friction plates ? Life will also be very affected by the way the bike has been ridden. I have seen alloy basket clutches finished by 6000 miles. More sympathetic riding gets 14,000 plus. Steel baskets/sintered friction do more miles. Andy
No idea what the 999R OE clutch is. My 748R slipper has a steel basket and sintered friction plates but my 1098R slipper has an Ergal (aluminium alloy) clutch and organic friction plates. I’m still on my original 748R clutch at about 12 or 13000 miles but my second 1098R clutch at less than 7000 miles. Andy