I was having a conversation about this the other day on another chat site.
I've done several "Band-Aid" fixes in the past to help get more heat from my warmers, great stuff foam inside the bars, add a layer of gasket material, etc. They help, but IMO the stock warmers still don't put out a whole ton of heat.
I remember about 10 years ago riding my F7...Bars would get so hot they would give you 2nd degree burns if you didn't turn them down, but they why do the bars on our newer sleds suck so much?
Simple answer and all it take a circuitry. The Firecats used to have 4 hand warmers positions: off, low, med, high. Same style heating element as our current sleds. But the difference is, when on "high" both the high and low resistor elements are energized providing far more heat than having just one on at a time.
I wish there was a simple way to wire this up. One method would be to get the old style hand warmer block from a firecat. What would be even better is if someone could design a little block of some sort, like what comes with the heat demon handwarmers that would give us more control over the heat output of the warmers.
I'm looking into some options...more to come