Above: This is a head off an ST4/ST4S and Post 2000 spec S4, 748, and S4R motors. Look at the rocker pin cover between the cam covers. If the cover has 4 bolts then you have a non-ST-head desmo, meaning the belts on this page will fit. If you have 5 bolts (one on each corner and one behind the oil line in the bottom center of the cover), then you need the ST4 belts sold HERE
Bucci Brand Cam Belts with Kevlar Reinforcement - $58/set
Bucci cam belts are made by GioCaMoto. They are kevlar lined and are identical to the OEM Gates-Built belts. The OEM belts retail for $120 a set. You can grab a pair of the Bucci ones here for $60. What a deal!
These belts will fit 851-888, 916-996 bikes, and all pre-2001 748/S4 models. These Belts WILL NOT work on the ST4/ST4S or post-2000 748 and S4 models. Belt purchases are non-returnable.