Recently I bought a used Savage with only 3,800 miles on it, and the right side rocker and cam were badly worn.
There have also been a couple of other bikes on the forum that have this same issue, and it got us to speculating that the damage is caused by idling the bike while it is resting on the side stand. There is a small rectangular oil well beneath the cam, and when the bike is leaned over onto the side stand, the oil is moved over to the left side (intake) cam lobe, and the right side (exhaust) cam lobe may not get any oil to dip into.
More recently I have been looking at the way the upper end is lubricated, and I believe the system also tends to starve the right side cam lobe when the bike is on the sidestand and idling. The oil is fed up through the cylinder and into the cylinder head. There are oil passages that are drilled to take the oil to each one of the cam journals and lubricate them. The left side cam journal is closed on the end, and the cam has a small notch on the left side that allows the oil to feed into the left end of the camshaft - which is hollow. The oil goes into the left side of the camshaft through a large hole, and travels along the hollow camshaft to the right side, which has a small hole at the cam gear end. As the oil travels through the center of the camshaft, it first comes to a small hole that is drilled into the base of the intake cam lobe, and it allows oil to pass through the cam to lubricate the intake rocker just before the valve begins to open....and what oil doesn't pass through this hole continues to travel to the hole that is drilled in the exhaust cam lobe, where it can flow out the hole to oil the exhaust cam lobe and rocker..........and whatever oil is left over continues to the right side of the cam and it flows out the end and lubricates the cam chain and chain guides.
So....when the bike is on the side stand and idling slowly, the oil pump is flowing very little oil, and most of that oil flow goes to the bottom end, and a small amount of oil reaches the cylinder head. What oil does reach the head first goes to the cam bearings, and then the left side cam bearing allows some oil to flow into the left side (downhill end) of the cam. The small amount of oil most likely travels to the intake cam lobe which is on the left/downhill side, and it flows out the hole drilled in the intake lobe of the cam.......most likely on the bikes that were damaged there is little or no oil left to climb up the hollow center of the cam to get to the right side exhaust lobe, and it gets starved for oil and is damaged. Once the damage begins and the cam and rockers are scored, I believe the wear accelerates and occurs even when the bike is level and up at operating speed.
So, I believe the bike should never be started and allowed to run on the side stand. The folks who like to start their bikes and let them warm up on the sidestand while they put on their gear may be doing more harm than good. My recommendation is that you put your gear on, get on the bike, turn on Raptor petcock if you have one, grab the handlebars adn pull the bike upright and fold up the sidestand, pull on the choke if you need to, and then start the bike. Warm the bike up while holding the throttle open a bit to provide a fast idle for 30 seconds to a minute - then push in the choke and ride off slowly and don't apply a lot of throttle for a mile or so and allow the engine to warm up gently. (If you need the choke to ride smoothly for a mile or two then leave it on, and push it in when the bike will run smoothly without the choke).
And it is vitally important that you keep the idle speed up above 1,000 rpm.
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