G Glester New member Jan 28, 2015 #1 I'm gonna use a yz450f motor. It's a 2013 model. I know yamaha calls for 10w40. Should I use that viscosity or something lighter or heavier for kart racing?
I'm gonna use a yz450f motor. It's a 2013 model. I know yamaha calls for 10w40. Should I use that viscosity or something lighter or heavier for kart racing?
