Are these 380 and 410 monsters over bored or over sleved cylinders from a smaller machine or designed for the displacement? I know we do a lot of work on banshee's (or RZ 350 for the road only guys) and the biggest problem with big over bores is as the cylinders get bigger the transferes get smaller. Pretty self defeating! your almost better to run stock displacement and run it to the moon! Thats why I love my 300 because Honda designed the port layout for 300cc's. But hey you know theres no replacement for displacement!!!
_________________
1995 A kit TZ 250
1994 Rothmans NSR 300sp SOLD
1998 RM 250 freestyle/motorcross
1998 Meathanol burning CR 500 AF super retard/motorcross/sand dunes/play bike