To avoid rust particles and other gunk getting into the carbs, it is highly recommended that a fuel filter be installed on these bikes. The challenge is that there is very little room between the tank and the carbs to ensure a good downward flow of fuel. The use of a 90-degree filter seems to help and prevents kinks in the fuel line.
Close-up of a 90-degree filter showing direction of fuel flow
Filter with fuel line attached
Filter fitted with tank still raised
Filter fitted with tank in normal position
The 90-degree fuel filters can be purchased online from www.heeter.com. Click here to access the page featuring the fuel filters.