Above you’re looking at a side-by-side comparison of the factory supercharger pulley and the new billet pulley from Kspeed, which is a direct replacement for stock wheel. As you can see, the factory pulley is quite a bit heavier, and for those who already know, are prone to rusting.
The Kspeed pulley comes in at half the weight, which means a quicker spool time and (in the case of the 108mm pulley) 1.2psi more boost, putting the total closer to 18psi. Kspeed makes each of their pulleys from aircraft grade billet aluminum alloy and has them anodised for superior protection from salt and corrosion.
Kspeed offers two sizes of their lightweight pulleys too: the 109mm pulley can “go on any ski, and is a cheaper replacement option than [stock],” according to them. While you’ll see a slight boost increase, you won’t get the “full effect” until you reflash the ECU. The 109mm costs $212 AUD.
For those looking to really increase the boost of their supercharged Kawasakis, Kspeed’s 108mm pulley is their race spec offering. For this one, you MUST run 98-octane fuel (Australia) or 93-octane (USA). It also comes with a new idler to reduce belt slack. The 108 is priced at $250 AUD.
