Heat "Shields"
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From: Fort Myers
Heat "Shields"
After a leg burn yesterday decided to pull of the heat shields and wrap the pipes underneath putting the shields back on afterwards. As you're aware, the heat shields are mounted with 3 screw clamps completely contacting the pipes and obviously transferring the heat through those solid metal connections. For those that are anti-wrap has anyone just wrapped underneath the clamps to cut down the metal to metal heat transfer??
Hard to say how this would play out. It seems to me there are two main ways the heat is getting from the pipe to the heat shield:
1. conduction, through the metal-to-metal contact clamps, and also via the pipe heating the air, which then heats the heat shield.
2. radiation (infra red coming off the pipe, heating the shield directly).
In its standard trim, a heatshild will get some conduction via the clamps, and a bunch of radiated heat from the pipe. But conducted heat via the air is minimised by the wind (when you ride) blowing the warm air away, and the 'open' design of the heat shilds allowing the hot air to convect away even when the bike is stopped ('hot air rises' kind of thing...).
I'm guessing but it seems to me that applying wrap to the pipe under the heat shields would likely reduce the radiated heat, but (as the wrap would act likle a blanket tending to trap the hot air in the space between the pipe and shield), the conducted heat might actually increase.
Might be interesting to do the experiment - get a thermometer reading of the shield, wrap it then test it again...
1. conduction, through the metal-to-metal contact clamps, and also via the pipe heating the air, which then heats the heat shield.
2. radiation (infra red coming off the pipe, heating the shield directly).
In its standard trim, a heatshild will get some conduction via the clamps, and a bunch of radiated heat from the pipe. But conducted heat via the air is minimised by the wind (when you ride) blowing the warm air away, and the 'open' design of the heat shilds allowing the hot air to convect away even when the bike is stopped ('hot air rises' kind of thing...).
I'm guessing but it seems to me that applying wrap to the pipe under the heat shields would likely reduce the radiated heat, but (as the wrap would act likle a blanket tending to trap the hot air in the space between the pipe and shield), the conducted heat might actually increase.
Might be interesting to do the experiment - get a thermometer reading of the shield, wrap it then test it again...
Last edited by Davdoodles; Dec 23, 2015 at 05:44 PM.
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From: Minnesota
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From: Doghouse... mostly
You ride the bike for a few hours non stop and those heat shields are gonna be a lot hotter than 125, I'll guarantee it.
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Joined: Dec 2015
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From: Fort Myers
I'm sure you're right..my test was only after 10 minutes of hard riding and about 3 minutes of idling. I have found significant heat reduction on wrapped pipes in other applications especially experimental aircraft. I barely brushed my leg on it while digging for my key after it was heat soaking in the Harley lot for 10 minutes. I'm hoping to just cut it down some. I'm sure I'm not the first to sport a burn mark. I can understand the always wear long pants guys that live in a state with 2 weeks of summer (half of which rains). I actually agree with them and on any trips in excess of 50 miles I do that. But I'm not giving up shorts for local trips.
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From: Minnesota
Sorry, but you will to get more leg burns.
Look at it this way dude, if there was a way to completely keep the pipes on these thing cool enough to not burn anyone,, it would be common knowledge and the factory would probably already be doing it.
Sooner or later you'll figure out that pipe burns hurt.
Look at it this way dude, if there was a way to completely keep the pipes on these thing cool enough to not burn anyone,, it would be common knowledge and the factory would probably already be doing it.
Sooner or later you'll figure out that pipe burns hurt.