Can I convert the Oil Tank on a Wave Venture to a "Reserve Fuel Tank"

[WFO Speedracer]

Connect the Tanks in Series with the Small Tank holding the only Vent Check Valve. Install the Large Tank Vent Check Valve onto the Small Tank.

The Small Tank does not need any Fuel Pickups.

So connect the Oil Tank Bottom Nipple directly to the Large Fuel Tank VENT Nipple. This will allow the Oil Tank to Gravity Feed the Large Fuel Tank.

Only one Vent is needed since both Tanks are connected. As the Large Tank Fuel is consumed, the Vacuum will draw from the Small Oil Tank. If the Vacuum becomes excessive, the Small Oil Tank Vent will allow Air into the Dual-Tank System.

Should refill the Large Tank First and then the Small Tank.

The Rider from Mexico did this on his X-2 to extend riding time. And it worked.

That will work also that is how they do it on auxiliary motorcycle tanks either mounted to the handlebar or numberplate

 

[E350]

@WFO Speedracer the benefit of this arrangement is that there is still a "reserve" selector switch and a reserve port (longer fuel pickup in the system) because the fuel pickups stay where they are now in the oem larger/original fuel tank:

Connect the Tanks in Series with the Small Tank holding the only Vent Check Valve. Install the Large Tank Vent Check Valve onto the Small Tank.

The Small Tank does not need any Fuel Pickups.

So connect the Oil Tank Bottom Nipple directly to the Large Fuel Tank VENT Nipple. This will allow the Oil Tank to Gravity Feed the Large Fuel Tank.

Only one Vent is needed since both Tanks are connected. As the Large Tank Fuel is consumed, the Vacuum will draw from the Small Oil Tank. If the Vacuum becomes excessive, the Small Oil Tank Vent will allow Air into the Dual-Tank System.

Should refill the Large Tank First and then the Small Tank.

The Rider from Mexico did this on his X-2 to extend riding time. And it worked.

But what about bored&stroked's concern?

Doing that would mean the return for the carbs would have to force the gas back into the large tank basically under pressure from the weight of fuel pushing down?

 

[WFO Speedracer]

@WFO Speedracer the benefit of this arrangement is that there is still a "reserve" selector switch and a reserve port (longer fuel pickup in the system) because the fuel pickups stay where they are now in the oem larger/original fuel tank:


But what about bored&stroked's concern?

I believe you are putting way too much thought into this , the simplest way is make it a dedicated Primer tank, the other ways will work, I wouldn't worry about the return line the treturn is already under pressure if it wasn't it wouldn't return, piggybacking the tanks does not interfere with the way they operate separately .

 

[E350]

Position is less verticle more side by side: