The last two times I've ridden my CB (25 miles one-way, and 54 miles one-way), I've basically gotten the insides of my thighs cooked (my skin was red and it was very uncomfortable after about 20 minutes).
Now, it has been very hot out, as it usually is in southern Arizona during summer (> 108*F), so that's probably a contributing factor, but I was just wondering if anyone else has had this problem. Coming back from the last go 'round, I couldn't wait to get off the bike. The CBR gets really hot, too, but the heat wafts up from the engine at stops, not while riding.
I don't sit particularly close to the tank, however I do keep my knees pinned to the tank as much as possible because it affords better control of the upper body. Both trips were mostly highway @ ~70mph most of the time. I filled the tank before coming back last time, because I've noticed in the past that cool gasoline in the tank does a decent job of insulating me from heat, but that didn't matter this time. At no time did the engine oil overheat light come on, so I have to imagine the engine was within normal operating parameters with regard to temperature. I'm guessing the engine is making the tank very hot, since that's the only thing my legs are touching. This is the first time I'm noticing this, but I don't recall how often I rode in the extreme heat last summer, if at all.
Thoughts?
While I can't speak directly to the CB1100 since I don't own one yet... I can say that when it's over 90 degrees here I feel the heat coming off of any bike that I ride unless it's my little 400 Twin. I think it's any larger displacement engine will throw heat off toward the rider. I feel it only a little on my legs but not to the point where my skin gets red. But I do always wear either Kevlar reinforced pants or a riding suit. I don't think your bike is cooking the gas in the tank, it's more likely that the heat is rising from the engine and flowing around the outside of the tank, making it seem to you that the tank and it's contents are heated.
Just my thoughts.
Wow, you are a pretty tough guy riding in that kind of heat.

I don't enjoy it much around here when it's over 90, let alone 108! Given that a steak is cooked rare at 120-125, it seems it wouldn't take much engine heat on top of ambient temp. to fry you pretty good.
I think it's your riding conditions as I was commuting 115 miles a day with none of your described symptoms.
The few times I've been out in really hot weather (> 108F in the Utah Desert), I've found that leather wear gave decent protection from the heat. I could feel how HOT the outside of the clothing was getting. To keep cool meant stopping often to dump water inside my clothes. It sure didn't take very long for it all to evaporate even from inside the jacket and pants. I imagine that I was quite a spectacle at times stopping at a gas station to buy a large cup of ice which I would then just dump inside the front of my jacket and down the inside of my pants, ah relief !
(edit to clarify) Both the jacket and the pants were leather. Also on that particular trip I was on the road in that heat for about 200 - 250 miles. I carried a LOT of water with me, mainly for evaporative cooling.
It hasn't been that [i]hot in Florida, but the temps have been in the 90's with a heat index of 100+. I have noticed heat from the engine flowing along my legs at slower speeds, but not to the point of discomfort like you describe.
However, on Saturday for the first time ever, I got the legendary TINK TINK TINK sound after a long ride as the bike cooled off in the garage.
in high heat, wear pant, light ventilated leather jacket and high boot will protect your skin and legs.
(08-05-2014, 05:41 AM)cbdtran_imp Wrote: [ -> ]in high heat, wear pant, light ventilated leather jacket and high boot will protect your skin and legs.
I always wear a leather jacket (white, perforated Alpinestars), perforated leather gloves (also Alpinestars), boots (Sidi), and full-face helmet (Shoei) and long pants, albeit just blue jeans.
Just the insides of my thighs, the part touching the tank, are getting cooked. Everything else is fine*.
* As fine as one can be in this kind of weather - obviously one will will sweat no matter what, but I'm used to that.
I usually ride in temps of 90s and I have noticed that the heat from the CB is noticeably hotter than my previous bike (a Honda water cooled Shadow 750 cruiser). The increase in heat is noticed in slow traffic as well as when riding on the freeway going 50 mph but the heat is not unbearable. So I would imagine riding in temps of 108 would be uncomfortable.
The CB also takes much longer to cool off after my rides. I do not have a garage so I rely on a cover to protect the bike from the elements. With the CB, I usually need to wait about 4 hours after riding before I can put the cover on the bike whereas with my previous Shadow it would take about half the time to cool. I guess that is the nature of the beast with air cooled engines.
(08-05-2014, 05:46 AM)AzBob_imp Wrote: [ -> ] (08-05-2014, 05:41 AM)cbdtran_imp Wrote: [ -> ]in high heat, wear pant, light ventilated leather jacket and high boot will protect your skin and legs.
I always wear a leather jacket (white, perforated Alpinestars), perforated leather gloves (also Alpinestars), boots (Sidi), and full-face helmet (Shoei) and long pants, albeit just blue jeans.
Just the insides of my thighs, the part touching the tank, are getting cooked. Everything else is fine*.
* As fine as one can be in this kind of weather - obviously one will will sweat no matter what, but I'm used to that.
I always wear a leather jacket (white, perforated Alpinestars), perforated leather gloves (also Alpinestars), boots (Sidi), and full-face helmet (Shoei) and long pants, albeit just blue jeans.
Just the insides of my thighs, the part touching the tank, are getting cooked. Everything else is fine*
* As fine as one can be in this kind of weather - obviously one will will sweat no matter what, but I'm used to that.
I ride in heavy Kevlar-lined jeans, and feel no engine heat at all. They are plenty warm just having them on, but maybe insulate from external sources? I do remember one time, when I first got the CB, I rode in shorts (I know, I know...), and engine heat really cooked my shins, even while moving. So I learned another reason to always wear proper gear pretty fast.