I have seen accessories for the Honda Exhaust systems but not for the Yamaha.
Here is a
LINK for the Honda Generator...
My 2kW Honda gets rather warm when running. I don't think I would ever run it in an small enclosed area just because of the generated heat...
There is also the other reason for putting deadly CO FUMES into the trailer enclosed areas. This is a silent death sentence... If I point my 2KW Generator towards my trailer I can trip the Co DETECTOR just running the generator from my truck tail gate area... This is some serious stuff...
My 2KW Honda generator sits secured to my covered tailgate corner in my truck. When I need to use it I pull it out onto the tail gate... My generator is out of sight when secured and goes where I go...
In my case I only use my 2KW Generator to power up my 30A Shore Power Cable to run my on-board CONVERTER/CHARGER unit to charge up my trailer battery bank. Since my Converter/Charger is a smart mode type this takes around three hours of generator run time to get my 50% 255AH depleted battery bank back up to its 90% charge charge state. Then I am good again to run all of my 12V items from the battery bank and selected 120VAC items from my small 600w PURE SINE WAVE Inverter.
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Roy Ken