changing exhaust cam dynamics?

[Anonymous]

i am rebuilding a 1982 gs 650g, and i was curious as to wether or not it is possible and/or a good idea to retard the exhaust cam a tooth to try and create valve overlap, increasing crossflow at higher rpm's. i dont even know if its an interference fit engine or not. anyone?

thanks, Ian

[Billy Ricks]

Altering timing by one tooth is going to probably change timing by around 10 degrees, just depends on how many teeth are on the sprocket. If you want to play with timing slot the gears.

[Anonymous]

what do you mean by slotting the gears?>

[Billy Ricks]

Elongating the two holes in the gears that are used to bolt the gears to the cams so you can adjust cam timing. You have to be careful when playing with cam timing. You can end up with pistons slamming into valves.