http://www.horseapple.com/Valkyrie/Tech_Tips/Fuel_Shutoff/fuel_shutoff.htmlRecommend the bigger 1/4" orifice DM if you have a high fuel demand setup. eg., you pull a trailer, or it's a trike or hack. Be careful to keep the fuel line level or slightly downhill. If you need more space on the fuel line say to install a filter, you can get more by changing to a brass T that screws into the DM to replace the OEM plastic one at the junction to the fuel rails. Be careful on the filter if you add one - starvation can be caused by the wrong one. On the brass T and also a pic of the bigger DM see my install at
http://www.valkyrieforum.com/bbs/index.php/topic,84264.0.htmlMy DM's on Jade and Deerslayer are set up as a fuel security system, mentioned in both links above. If the DM isn't manually turned on by pressing a hidden pushbutton, the bike will be out of fuel in a mile. Also, the DM is shut off by ignition sw, kill sw, or if the bike tips over - and the button must be pushed to turn it back on, after the ignition is on.