ihasabike wrote on 08/02/17 at 02:34:22:Regardless of top speed, I was under the impression we need to keep RPMs at or below about 4200 to avoid damaging heat. My bike has a tachometer and I'm hitting 4200 RPMs on my S40 at about 65 mph, which creates a quandary in the local 75 mph zones. I'm finding I need to cruise at about 4500 RPMs just to go with the flow in the slow lane.
Where did you read that 4,200 rpm is a "do not exceed" rpm? I do agree that the engine "sounds" like it is running pretty fast when you get it spinning up that fast - but I don't believe it will overheat.
When I had the Trail Tech Vapor on my bike and stock gearing, I found that on back roads and speeds below 60 mph, the head temperature stayed around 240 degrees in the hot 90 degree summer days. If I got on the highway and rode at 70-75 mph the head temps would go up to 280 degrees. The hottest head temperatures I ever got were in the 300 degree range - and they occurred when I stuck in traffic in Gatlingburg, and on a steep 1st gear climb up a gravel road when it was about 95 degrees in the shade.
I don't believe the Savage will overheat at highway speeds (not sure about that if you are like Serowbot and live where the temperature can get to 112 degrees) - however the bike can start to use oil at sustained high speeds...so you need to keep track of your oil level. You may want to consider getting a Kawasaki 25T pulley or a 140/90-15 rear tire is you do a lot of highway riding at 70+ mph.