The rs1 is pretty fuel efficient. 130-140 miles on a tank of you stretch it. One thing I noticed about my rs1 is when I have 1 bar it only takes around 7.5 gallons to fill. So it's still got a bunch of fuel. I have stretched it to 135miles a few times and was still on 1 bar. As for rotopax I have used them B4 but they are pretty small. Normally 2.5 gallon or less. I don't c any reason why you couldn't put one or 2 on the rh side or on the back with a mount

 

I used a Gzila Designs offset Rotopax mount to install a 2 gallon Rotopax on the LH side. Thankfully, the Lord was smiling on me and everything just barely fit! However you do it, avoid mounting the tank on the RH side over the exhaust manifold.

The trail ride we were going on was about 100 miles and I was concerned the machine might not make it. But, I checked the mileage over an 80 mile run and was getting about 17 mpg. So with a 2 gallon reserve, burning 7 gallons will get you about 119 miles (forest roads combined with elevation climbs of about 2000 ft).

 

Made a side mount 3 gal works great
jeff

 

thanks for the pics. The 3 gallon may be a good option. I mainly need to haul extra fuel for my sons atv on long rides