I read the discussion on the product spare fuel
I agree with most people about get gas when it reads 1/4 tank
Although I do have a great use for spare fuel.
I ride bikes and many have no gauge, one has a reserve valve that tells you get gas.
I have a BMW with only a light that comes on, but you can ride more than 50 miles after the light is on.
I bought the 32 oz metal gas container sold at sears and other hardware stores for lawn mowers.
I fit this in the trunk or side bag and it takes some of the worry out of “Will I make it HOME?”
If you ride a motorcycle with no fuel gauge, and you think you might not make it home, and you aren’t riding across Death Valley, you probably shouldn’t be riding a motorcycle. I say that will all seriousness.
I ride a 2005 Honda Shadow Aero. It’s got a 745cc engine and a 3.7 gallon fuel tank with a 0.9 gallon reserve, and no fuel gauge. I know that when I am commuting in stop-and-go traffic, I can ride about 120 miles before I have to switch to the reserve, so I usually buy fuel every 100 miles to save myself the trouble. When I take long distance rides on this motorcycle, with a full-size windshield, lower air deflectors, and loaded saddle bags, I can ride about 90 miles before I have to switch to the reserve, so I stop for fuel every 80-100 miles.
If you know your motorcycle, you should know how far you can make it before you have to switch to the reserve fuel source, and it should never be necessary to carry extra fuel. The single exception would be if you are riding across a secluded section of highway, like in Death Valley. You shouldn’t need to carry extra fuel for everyday riding just because you don’t have a fuel gauge.
I never ride past a gas station without stopping when I am riding on reserve fuel, and that’s kept me from stranding myself.
One last thing I would like to add is that taking a long trip on a motorcycle is a little like backpacking. Space for luggage and gear is so sparse, and so valuable, you don’t want to carry anything you don’t plan to use. Carrying spare fuel in these circumstances seems wasteful to me. I’d rather use that space for a first aid kit, or tools, or dry clothes, or camping gear, or many things that are more likely to be needed on a long trip.