You'd think I could find this information on the web somewhere but this time Google is truly not my friend... :depressed:
My UltraStar is pretty much stock, with the Cuyuna engine and two 1.75 gallon tanks forward of the seat, under my legs, and the little rectangular Mikuni pump. To this setup I've added an additional 1.5 gallon tank behind the seat, which drains into the main tanks. I haven't had any trouble with this setup, but...
There are several different float / needle sizes available for the Mikuni VM32 carburetor on my engine. The one I have is the smallest (1.5mm), and is intended to be used with a fuel pump. The larger sizes are for gravity feed. I'd like to replace the three tanks with a single 5 gallon tank mounted above the engine, using gravity feed to eliminate the fuel pump (one more potential point of failure). However, I can't find anywhere the information on how much height is required for adequate fuel flow. I wouldn't think it's much, since motorcycle tanks (the VM32 is a popular motorcycle carb) are mounted very close above the engine, but it'd be nice to know the actual spec.
Moving the tank this way would free up the space in front of the seat for a small storage area... sometimes you really want that warmer jacket for the flight home on a chilly day, as I found out last month...
-Dana
What has four legs and an arm? A happy pit bull.
My UltraStar is pretty much stock, with the Cuyuna engine and two 1.75 gallon tanks forward of the seat, under my legs, and the little rectangular Mikuni pump. To this setup I've added an additional 1.5 gallon tank behind the seat, which drains into the main tanks. I haven't had any trouble with this setup, but...
There are several different float / needle sizes available for the Mikuni VM32 carburetor on my engine. The one I have is the smallest (1.5mm), and is intended to be used with a fuel pump. The larger sizes are for gravity feed. I'd like to replace the three tanks with a single 5 gallon tank mounted above the engine, using gravity feed to eliminate the fuel pump (one more potential point of failure). However, I can't find anywhere the information on how much height is required for adequate fuel flow. I wouldn't think it's much, since motorcycle tanks (the VM32 is a popular motorcycle carb) are mounted very close above the engine, but it'd be nice to know the actual spec.
Moving the tank this way would free up the space in front of the seat for a small storage area... sometimes you really want that warmer jacket for the flight home on a chilly day, as I found out last month...
-Dana
What has four legs and an arm? A happy pit bull.