Easy Rider
Santa Cruz Scooter Works
The 6.4 has a differnt ignition. We prefered the 5.8 because it revs higher. The 6.4  had slighty a little more low end but couldn't hit the last power band. I think the S6 - S 9.4 hp is a 50cc motor but I'm not 100% sure.
	
		
			
		
		
	
				
			
	

			
			
			
			
			
			