Anyone besides me got over 8500 miles on thier 400 yet? If so do you guys think it's really nessasary to ck the valves every 3500 miles or do you think at some point it would only be nessarsary to ck them every 7000 or more. Have some of you cked them at 600, 4000, 7500 ect. and found that they didnot need adjusting? It seems like they are getting cked an awful lot.