Lately I've been riding the Savage to work daily.. Leave at around 7-8am when it's a bit chilly out (45-60 degrees usually) and the bike runs like a champ, great throttle response, acceleration, and very very little foot vibrations (handle bars don't change). and the bike feels like it could climb all the way to 85mph without skipping a beat.

But on the way home between 5 and 6pm after it's warmed up (70+ dehrees).. the bike seems like it's struggling a bit in every way.. acceleration is just a tad slower, the foot vibration on the brake side is UNBEARABLE, I find myself hovering my foot on the peg for a couple seconds every 4 or 5 minutes to give it a break and at 65 the vibration just makes the bike feel like it's doinga 10,000rpms or something.

And on warm WINDY days.. anything over 45 is just an accident waiting to happen.

Right now my bike is averaging 35-45(rarely)mpg..
No aftermarket parts.. stock exhaust and everything but it's got the largest pilot and main jet in it from Lancer.. Nothing else was done to the carb, the washer mod was not done.

The fact that the bike seems to run better in the morning may point to a little more moisture in the air, almost like a little water injection. The bikes are light and fairly wind sensitive. Can't help with the source of the vibration. Is the front wheel properly balanced? Are the forks well serviced? How old are the tyres?

I had to rejet because a few months back, after the bike finally started running after many many years.. it decided that after about 2000-3000rpms it would jerk VERY violently through every gear to the point that the bike topped out at pretty much 25mph

We assumed it was because the previous owner straight piped the bike.. but after spending the money on a stock exhaust that didn't fix it (bike was WAY too loud anyways).. then after buying the jets the problem was fixed

If I can track down where I put the jets lancer sent me I may go down a size or so.

As for the forks/tires... front tire is cracking, definitely need replaced soon.. forks have never had anything done to them that I'm aware of..rear tire is practically brand new.

I never thought about the moisture being like water injection.. never even knew that was a thing..

07s40scotty wrote on 10/17/12 at 15:02:39:

+1...  you can't correct a clogged up carb with bigger jets....  it'll just get funky...

- can't think of anything that cause an increasing high freq vibe that gets worse when warm...
Old, cupped tires might do the opposite... (bubbles and cupping usually feel worse in cold tires)... ..  I'd replace the front one anyway... it might help...
Also,.. for bad vibes in general,... check the motor mounts, especially the top one on the head cover...