Motorcycle Repair: 1995 350 warrior, metal shavings, service intervals

Question
I just put a new top end on the machine and when I drained the old oil before starting it the oil filter is covered with metal shavings.  My question is, How can I flush the crankcase to ensure that there is no more metal shavings in the crankcase?

Answer
This is one of those time consuming jobs. Pull the drain plug and pour a solvent down through the filler hole most of it will run out the drain hole. The solvent will dilute the oil and may take some of the shavings with it. Then replace the drain plug and put in some light weight oil like 5w-20wt and run untill warmed up,drain oil and change the filter and put in correct weight oil and new filter run it untill up to operating temp and then change oil & filter again.The shavings should be less, put in fresh oil and filter then resume your riding time and service intervals. As far as the amount of solvent used try at least 1-2 qts worth. I have done the compressed air down through the filler hole to blow out excess solvent and shavings. It wont hurt it but it can be messy.