Auxiliary Fuel Tank

#1
I've been reading around here for the majority of the day and at this point I am in need of some guidance.

Correct me if I am wrong but the gist I got is there is 2 ways of adding an auxiliary fuel tank.

1. Drill into the tank and make an additional pep cock to run a hose to the main tank from the auxiliary.

2. Add a T connector to the vent hose and gravity feed?

-the height between the aux space and the main tank is significant enough that unless i need to get up to injector pressure, gravity feed will be sufficient.

If anyone could help point me in the right direction or provide the information needed to get this completed. I'd really like to have a larger range instead of resorting to a Jerry can, I have a few days longer than a month and I've tried to approach this problem before and given up.

I'm planning to get started in Iron Butt this summer with a trip from Northern WA to Southern CA. I currently have a 2005 GSX-R 600 with lets just say minimal fuel capacity. (I know, get a more suited bike for the ride.... However I enjoy the thrill of doing things outside the norm.)

Main tank (4.5gal tank)
Auxillary tank (3-5 gallon tank) (rear seat mounted 14" x 14" area)
 

DrNeo

Premier Member
#2
Beebowbow -

You're correct.The third option is to "T" into the fuel rail return line. If "T-ing" isn't an option, most people drill a plastic tank, but I assume your tank on the GSX-R is either steel or aluminum?

I'd be curious about what MPG you're currently getting... most would be hard pressed to stay in a sport bike tuck for more than 150/200 miles at a time. A decent gas stop should take you no more than 10 minutes tops. (A lot of top-level riders are in/out in under 8).

Even at a speed limit of 65mph, you still have ~8.5 hours of "off-bike" time in a standard SS1000.
 
#3
Tank: Steel

Based on some further research and process of elimination that no other method will work, I'm going to be popping a hole in the tank.
(ordered a bulkhead with some O'rings and some permatex gasket to get a solid seal)

MPG :
6th gear with a tail wind - 40mpg
Typically 30-34mpg though.

No fuel gauge only a warning light at ~.75gal reserve which comes on around 100miles.

I can get fueled up at a gas station in no more than 5 minutes in my current stock state. However I'd rather dictate my stops on when i would like to stop as opposed to being forced to stop at a gas station for every rest stop and then a gas station per ~80miles just to be on the safe side. At the end of the day my #1 priority is not SS1000, I'm just looking to have fun touring on a not-your-typical-tourer and I don't want the only sights i see to be different gas stations. I'm riding from WA > SoCal without any time restrictions and then on my way back SoCal > WA i plan to attempt SS1000.
 

thekaz

Premier Member
#4
Tank: Steel

Based on some further research and process of elimination that no other method will work, I'm going to be popping a hole in the tank.
(ordered a bulkhead with some O'rings and some permatex gasket to get a solid seal)

MPG :
6th gear with a tail wind - 40mpg
Typically 30-34mpg though.

No fuel gauge only a warning light at ~.75gal reserve which comes on around 100miles.

I can get fueled up at a gas station in no more than 5 minutes in my current stock state. However I'd rather dictate my stops on when i would like to stop as opposed to being forced to stop at a gas station for every rest stop and then a gas station per ~80miles just to be on the safe side. At the end of the day my #1 priority is not SS1000, I'm just looking to have fun touring on a not-your-typical-tourer and I don't want the only sights i see to be different gas stations. I'm riding from WA > SoCal without any time restrictions and then on my way back SoCal > WA i plan to attempt SS1000.
If you check out the model of bikes that have finished the IBRs I think you will be surprised ;)
I have done most of my IBA rides on a ZX12R which has a range of near zero LOL
Drilling a tank and adding a fitting is more work but is the best way IMO
 

OX-34

Premier Member
IBR Finisher
#5
beebowbow,

I've drilled the tank and fitted a bulkhead fitting on a half a dozen steel bike tanks and that way works just fine. Add an aux with some form of inline tap and you're ready for miles and miles of smiles.

There is another way. In your first post you mentioned the option of 'T'ing into the vent line. That does work but it may require a few fiddly fuel lines. You don't have to 'T' into the vent. Just take the vent line off the Suzuki tank and attach the outlet fuel line from your aux tank. No tap required. The Gixxer tank can be loosened and tilted back to stand just about upright to reach the vent line (next to the overflow line). The bike tank now vents via the aux tank vent.

When both tanks are full and you ride away from the gas station the fuel is pumped out of the bike tank by the fuel pump. That sucks fuel from the aux straight into the bike tank litre for litre. At the same time air is drawn (litre for litre) into the aux vent line from outside. Once the aux is empty the bike tank starts drawing in air straight through the aux.

The filling procedure is strict. Starting with the aux empty (it was empty in your shed) first fill the bike tank and put the cap on. Fill the aux and put the cap on.

Do not open the bike tank unless you are positive the aux is empty - otherwise fuel will pour out the moment you open the cap.

Do not fill the aux unless you are positive the bike tank is full. Otherwise you may create a vapour lock as there is a big bubble of air at the top of the bike tank.

That air can't get out and the aux fuel can't easily get in. If the bike seems to be starved of fuel out on the road when you know you have gallons on board this is the likely cause. Carefully open the bike cap and you will hear air hissing. Wait a bit and the fuel from the aux will start to flow and fill the bike tank to the top. Cap it before it overflows.

Mounting on a sports bike can be easy. Buy a spare pillion seat from eBay or a wreckers. Drill straight though it and bolt appropriately. Add some 'no tools' brackets to access the pillion grab rail mounts/bolts or just use some strong cam buckle straps to hold the tank rigidly. Removing the tank to take it back to canyon carving mode is then quick and easy with the key plus those simple mounts. Put your oem pillion seat back on. Leave the aux outlet line as your vent if you are regularly going to do LD rides on the Gixxer, otherwise just lift and tilt the bike tank and swap the aux and vent line back again.


This only a Givi box, but it will be something like this.

 

cacomly

Premier Member
IBR Finisher
#6
On my 2007 Sportster I had a bung welded into the bottom of my tank since there was no easy way to get to the back of a bulkhead fitting.
 
#7
Two bits of advice from my actual experience: If you drill into a steel tank for the fuel line addition, once you have the proper location, use JB Weld to completely seal the tap. Rubber oil rings can and will leak. Also, don't fill the tanks and leave the bike sitting in the hot sun or you may see fuel pouring out of the vents. DAMHIK.