Auxilliary Fuel Tank Venting - Yamaha RSV with Hannigan Conversion

Auxilliary Fuel Tank Venting - Yamaha RSV with Hannigan Conversion

Looking for some help understanding the venting of the auxiliary fuel tank on a Hannigan conversion. If I fill the auxiliary fuel tank on a hot day, gas expands and spills near right, rear wheel. Noticed today that filler pipe attaches to neck of tank with a radiator type hose. Upper band clamp was hand tight, and this is where fuel leaks. Bottom band clamp is very tight. Tightened the upper clamp today to stop the leaks, but now concerned about where fuel will expand since I removed this outlet. Is there some other venting. Does anyone know? Thanks!

Going to loosen up the top band clamp. Believe Hannigan meant it to be a release valve.

leo3wheel said:

Going to loosen up the top band clamp. Believe Hannigan meant it to be a release valve.

Click to expand...

Have you inspected for a release vent in the fuel cap area?

Looks like a solid chrome cap.

leo3wheel said:

Going to loosen up the top band clamp. Believe Hannigan meant it to be a release valve.

Click to expand...

i dont believe for a second anyone would use a loose clamp as a vent... why not contact hannigan??

Hi Leo sorry to hear you are having trouble. I would contact Hannigan and ask them how they vent that tank or if you are supposed to leave some head space. You have had that trike awhile, are you just now having trouble?

Hi Paul, Had our trike 10 years. Full auxilliary tank overflowing has been an issue since beginning. Recently changed rear brake pads and was watching for leaks. Well, weather has been super hot, so auxilliary tank overflowed. Took rear tire off to make sure bleeder was dry. While there, could see signs of gas leaking at filler tube. Tried to tightenen clamps, and found upper clamp was very loose. Tightened clamp and put wheel back on. Then wondered if I did the right thing. Don't want to introduce problems, especially since I'm going on a long trip this weekend. Worried about excessive pressure in auxilliary tank or problems transferring fuel to main tank. So went back in and loosened clamp again. Turns out another Hannigan owner has had same issues. Started thinking that maybe Hannigan set it this way intentionally. Will have to check with Hannigan, but right now my focue is on Northeast Rally this weekend. Cheers!