That is normal.
Two reasons.
1. The pump for the Aux Fuel System is electrically powered. When your trike is in motion, it's finite electrical power supply is being utilized to the max demand. With "supply" being static and "demand" being at its highest/peak, the power sent to each system is limited and therefore those systems on the outskirts of the trikes Grid are at a minimum. The electric fuel pump's output is working at a lower rate due to lower electrical input. Conversely when at stand-still idle, there is plenty electrical supply and minimum demand from the systems operating so the pump gets all it needs to operate a its maximum capacity.
2. The HMS Aux Fuel Assembly ties into the bike's existing fuel return line to the Primary Tank. When at Idle, the normal fuel supply hardware and assemblies are operating a minimum flow rate so the aux tank can "intervene & introduce" its supply at the easiest and fastest rate. When at full operating speeds and rate of flow, it is harder for it to interject itself into that return feed as the bike's normal fuel system requires and assumes the vast majority of the available conduit/hardware.
Hope this helps. To discuss further on this or any question you may have at this time or in the future, please don't hesitate to give us a call.
UPDATE. I called Roadsmith and described the parts I needed. Without hesitation, the parts person said, "Oh, you must have a Hannigan". The parts with instructions are being shipped this coming week. I will report on how it works out.
UPDATE: I received the parts from Roadsmith. If anybody else would like to do this modification, it is part number A-200-40 (REV A). If you are handy with tools, you should not have a problem. I finally was able to get in a ride and the fuel transferred on the move with no problem. I'm guessing it only took about 5 minutes or so to complete the transfer.
Don't get me wrong, I love my Hannigan. My wife is very comfortable and she says the ride is smoother than she thought it would be. I give it a 99.9% rating. If they were to change the fuel routing, I would be able to give it a 100%.
Hannigan doesn't like to fool around with the factory fuel tank, but this mod works like a charm. I added a 6 minute timer to mine so when it's done transferring the pump automatically shuts off so the pump won't run dry if you forget to flip the switch off.UPDATE: I received the parts from Roadsmith. If anybody else would like to do this modification, it is part number A-200-40 (REV A). If you are handy with tools, you should not have a problem. I finally was able to get in a ride and the fuel transferred on the move with no problem. I'm guessing it only took about 5 minutes or so to complete the transfer.
Don't get me wrong, I love my Hannigan. My wife is very comfortable and she says the ride is smoother than she thought it would be. I give it a 99.9% rating. If they were to change the fuel routing, I would be able to give it a 100%.
Please let everyone know how this works out. I would also appreciate a name and phone number as to where I can get the same parts and instructions.