Suzuki GS1000 Straight Cut Primary Gears
Whilst quiet running may be a desirable attribute in a road bike it is not necessary in a race bike.
Helical gears are effectively a very long pitch thread which imparts an opposite thrust on the crankshaft and the clutch transmission which reverses between power on and off. Not a desirable situation in a race engine.
The solution is to install “spur gears” which impart no side loads and will reduce mechanical stress and may even increase horsepower.
The crankshaft gear requires partial dismantling to install. The clutch gear is a direct replacement requiring the dismantling of the original and re-assembly and riveting to the new gear, (rivets are supplied).