Join Date: Apr 2012
Location: 9000 ft. ASL in Southwest Colorado, USA
Thanked 3,643 Times in 1,938 Posts
About ten years ago, when motocross switched from using 250 two strokes to 450 four stroke motors I was hoping that some of that technology would be used to create a lightweight, road going single with 40-50bhp. so far only KTM have shown any inclination to go down that route.
No doubt the current crop of 450cc four stroke motocross engines are a testament to the kind of power & performance can be achieved from a mid sized single cylinder. However, those engines are not built to withstand sustained operation over time at higher RPM's, which is a primary consideration for a road going bike. They are very "high strung" purpose built motors, where motocross & supercross tracks rarely demand more than 5 to 10 seconds of WOT over the longest straights before a rider is backing off for a tight corner, or when in mid-air over a big jump.
Former Factory Test Rider/Technician