Tag-Along Aux Fuel Tank (joe2lmaker)

[dcarver]

Don, dude! You need to get rid of the POS yellow hard plastic line and get yourself some high quality fuel line.

That looks like Tygon

<Link>

Correct. KaitsDad found some cool Tygon in blue, the best color, but I was not patient.

Do you think that you HAVE TO wait until a gallon of gas has been used? I mean, why not just leave the valve open? I am just picturing myself forgetting all about opening the valve 30 min later, especially on Day 9.
Also wondering if putting some spacers under the cell would help? Dale suggested raising the cell a bit and I don't see what it would hurt. My Sampson on the GS sits quite high and I never had any problems with the weight. This might give a bit more head pressure, no?

I too would like to see Skoot blowing his fuel cell. Awesome!

I don't think it's necessary to raise the cell, see below.

 

[dcarver]

I found what I think is a cool over-flow vent device. I'm never going to run an IBR, so a catch tank means nothing to me. This is a fuel pick up from a Husqvarna chain saw..

The installation -

Well now, somebody has to go riding to test this new tank... who, ME? :yahoo:

Just in case..

My first test scenario -

Empty main tank.

With full aux tank, and empty main, see if xnfr rate was sufficient to keep motoring.

..So I siphoned the main tank (pretty difficult to completely empty it using siphon hose)

.. Filled up the aux tank

.. went riding

Evidently, even with about 1/2 to 3/8" (visual, not measured) of gas in the main, it will start to starve and stumble. I made it less than 6 miles when sputtering happened. I could keep it alive if running about 45 - 50 and turning left and right. But the end was near. Thinking of dry fuel pump destruction horror stories, I stopped. And opened the aux tank.

Looking into the main, flow was evident. So off I went, riding at 45-65 depending upon traffic. No problems, the aux was feeding the main sufficient to keep the fuel pump happy.

At 30.5 miles, the fuel gauge went from flashing empty to 1 bar.

Corresponding aux tank level - notice is has dropped from 4/4 full to this -

At one point in time, I saw 2 bars on the fuel gauge. Then I wicked it up and had some fun in straights and corners, running at triple+ and pushing hard. Then, the blinking gauge came back on - I guess this means I was consuming more than delivering. (but I was pushing it, hard)

Back at the Hondarosa, I measured fuel height in main and aux

Main = 1 5/8

Aux = 1 3/8

Opened aux valve, weed whacked a mountain, came back later. BTW, FJR on center stand..

Main = 1 3/4, Aux = 1 3/8 to 1 1/4, depending upon my measuring 'technique'. Call it half way between.

I then siphoned the main -

Main = 1/2" at test start

with bike on center stand, 40 minutes,

Main = 1/2.

Bike on side stand - no change.

Evidently, once you're down to 3/8 to 4/8 in main or aux, you're a done doodle.

So what is learned from all this?

1. The aux tank will flow (given *my* configuration) down to 1/2"

2. If the main is empty, the full aux flows adequately to maintain motoring speeds (worst case scenario - who is stupid enough to run the main completley dry before opening the aux? )

3. At some point in time, at low levels, the aux and main 'equalize'

The next test?

Given a nearly empty main and aux, while connected, how far can one go?

That will be tomorrow.

I hope this helps -

and will be very curious to see what others experience, especially those that run 5/16" line not 1/4" like I have. Per SkooterG's post, all gravity tanks with minimal head pressure have 'issues', requiring a learning curve of what does and does not work.

From what I've seen today, Joe2lMakers tank feeds the main as it should!

I'll test more soon.

 

[dcarver]

Forgot this -

My first one way valve was from MacMaster-Carr. It failed miserably for gravity feed use due to a high 'pop-off pressure. Too restrictive.

Then I got to thinking of my dirt bikes... they have a cool 1-way valve that allows the tank to vent yet not allow gas to escape..

I gave it the SkooterG blow test and determined it was a prime candidate for use on Aux tanks..

20 USD from your local YamaMamma dealer, any Yz426 - Yz450...

BTW - it's not a perfect fit for 1/4" line, a tad undersized. For gravity systems, no problem is my guess (and I'll test) but most likely not suitable for pressurized systems.

 

[dcarver]

Left the aux valve open last night, bike on side stand - all gas flowed to main tank! :yahoo:

 

[dcarver]

Had a few hours before Easter dinner and company so I rigged up an external seat latch release device. My hands and fingers are too manly to release rider seat with aux tank and Bill Mayer saddle. Also,I envision a back rest, which would completely block access.

My first idea was to use some real cool wire 'rope', looped at each end, one end attached to the release tab, the other to grab and pull with. That idea failed miserably, so plan 'B', although less eloquent, was fully functional and implemented.

So, here it is, my idea, in all her glory..

Drill a pass-through hole.

Connect ty-rap to lever arm after first removing rubber 'boot' from arm. Ty-rap end to latch slot.

Note - this pix from abandoned idea..

Drill pass-through hole through plastic side plate.

Final installation -

If doing it again, the first hole would smaller diameter and to the right. I miscalculated the clearance from the plastic seat base bracket and metal thing I drilled the hole into. Then again, the larger hole lightened the bike by .185 grams thus improving top end speed!

Yeah, yeah, you machinists types will probably come up with some high dollar zoot suit stainless steel knurled and polished shaft... :****: :lol:

 

[dcarver]

The next item on the list was to install my yz426 one way check valve into the gas delivery line. This item is the cats meow excepting it's a *tad* undersized. Also, I learned that the QD fitting should be located somewhere else than under rider seat for easier tank removal, so I relocated it.

Here's the installed yzValve

It sealed no problem with 2 small zip ties.

 

[BIODSL]

I found what I think is a cool over-flow vent device. I'm never going to run an IBR, so a catch tank means nothing to me.

Just to clarify here, Chalmers requires a catch tank in his rallies as well (1088, Ten 'n Ten).

Interesting thread, DC. Thanks for keeping us up to date. Isn't aux fuel the best? Once you have it, there's no going back.

 

[daddyman]

OK, a little guidance desired here.

For an overflow catch tank, for IBA rules, are we talking about something like this installed along the vent line from the aux tank to the road?

Clicky

If not, please point me in the correct direction. I've been ok following the guidelines to this point... I think. <_<

 

[SkooterG]

Just to clarify on BIODSL's inaccurate clarification. Chalmer's rallies are the only rallies that require a fuel cell catch can. The IBA does not. Nor is it required in the IBR.

If you are running one of Chalmer's rallies and need to add a catch can, it doesn't have to be anything technical. Baby bottles have been popular in the past. Then there is always my favorite: Clicky

 

[daddyman]

Thanks for the clarification. I wanted to make sure as it seemed to me that the section indicated that as long as the fuel vented out away from the tire, etc. it would be good.

Would there be any reason to use the overflow tank, other than providing a small tank for vented fuel to collect rather than spilling on the road?

 

[RenoJohn]

Just to clarify on BIODSL's inaccurate clarification. Chalmer's rallies are the only rallies that require a fuel cell catch can. The IBA does not. Nor is it required in the IBR.
If you are running one of Chalmer's rallies and need to add a catch can, it doesn't have to be anything technical. Baby bottles have been popular in the past. Then there is always my favorite: Clicky

Just to clarify on SkooterG's INACCURATE clarification of BIODSL's kinda-accurate clarification.

All MERA rallies, including the UTAH 1088 do NOT require a catch can. *IF* you are using an tip-over valve such as the one I incorporated in my new aux fuel cel.

This tip over valve prevents gas from coming out of the vent in the event of a tip-over. In normal conditions it acts as a traditional vent. While acceptable as shown, I will have a fitting and vent tube on this ven when this cel goes prime-time.

 

[Go Far]

I don't have a copy of Chalmer's rules but isn't one of the issues with bikes filling up the night before a rally- then having the warming, expanding gas run all over the hotel parking lot? I have an in line filter in my vent hose, and that has qualified as my catch can.

Just to clarify on BIODSL's inaccurate clarification. Chalmer's rallies are the only rallies that require a fuel cell catch can. The IBA does not. Nor is it required in the IBR.
If you are running one of Chalmer's rallies and need to add a catch can, it doesn't have to be anything technical. Baby bottles have been popular in the past. Then there is always my favorite: Clicky

Just to clarify on SkooterG's INACCURATE clarification.

All MERA rallies, including the UTAH 1088 do NOT require a catch can. *IF* you are using an tip-over valve such as the one I incorporated in my new aux fuel cel.

This tip over valve prevents gas from coming out of the vent in the event of a tip-over. In normal conditions it acts as a traditional vent. While acceptable as shown, I will have a fitting and vent tube on this ven when this cel goes prime-time.

 

[Joe2Lmaker]

I have an in line filter in my vent hose, and that has qualified as my catch can.

That was my plan too.

Vent out the top of the tank into the bottom of a largish fuel filter out the top of the filter and the line routed back past the tire.

edit: the loop in the line doubles as a tip over valve.

 

[SkooterG]

Would there be any reason to use the overflow tank, other than providing a small tank for vented fuel to collect rather than spilling on the road?

None whatsoever. The FJR's main tank has two paths (hoses) to ground - one for the vent, one for the overflow.

Just to clarify on SkooterG's INACCURATE clarification of BIODSL's kinda-accurate clarification.

Ouch!

I have just had my ass handed to me by a hick from Nevada. Who's riding my bike!

 

[RenoJohn]

Ouch!
I have just had my ass handed to me by a hick from Nevada. Who's riding my bike!

Had to pounce, not often I get to clarify the clarification done by my true idol.

edit: the loop in the line doubles as a tip over valve.

Not sure how many folks would consider a loop in a vent tube a tip-over valve ....but if you say so (??)

 

[Udjeni]

I don't know much about this, other than that I have a gravity feed aux tank with which I have had flow problems from time to time (so SkooterG's posting on the topic earlier was very interesting), but the above picture set off alarm bells in my mind. It seems to me that little kink in the fuel line, on the main tank's side of the cable-tie, is looking for trouble. That little air bubble you can see sitting there seems to me to be enough to cause an air lock, preventing fuel from flowing from the aux tank to the main tank under certain conditions.

Is this the final routing of that fuel line, or is this just a temporary setup while you are testing out things? I would be nervous routing the line so close to places where it can get squeezed/deformed each time the seat is removed (or rather put back). But that's just me and what do I know? :huh:

 

[Joe2Lmaker]

Not sure how many folks would consider a loop in a vent tube a tip-over valve ....but if you say so (??)

I don't make this stuff up.

If properly placed, a 360° loop in the vent line is an optional rollover check valve.

It's in some racing rulebooks.

The JAZ website also recommends 360° loops in the vent line.

There must be somebody following this who understands how it works. :dntknw:

I just adapted the idea to work with a fuel filter (acting as the vent's air filter) doubling as a puke tank.

It seems to me that little kink in the fuel line, on the main tank's side of the cable-tie, is looking for trouble. That little air bubble you can see sitting there seems to me to be enough to cause an air lock, preventing fuel from flowing from the aux tank to the main tank under certain conditions.

I think dcarver is trying keep the fuel line in the same plane (as much as possible). I see the air in the line, but I don't see any pinch point or kink.

 

[dcarver]

I don't know much about this, other than that I have a gravity feed aux tank with which I have had flow problems from time to time (so SkooterG's posting on the topic earlier was very interesting), but the above picture set off alarm bells in my mind. It seems to me that little kink in the fuel line, on the main tank's side of the cable-tie, is looking for trouble. That little air bubble you can see sitting there seems to me to be enough to cause an air lock, preventing fuel from flowing from the aux tank to the main tank under certain conditions.

Is this the final routing of that fuel line, or is this just a temporary setup while you are testing out things? I would be nervous routing the line so close to places where it can get squeezed/deformed each time the seat is removed (or rather put back). But that's just me and what do I know? :huh:

The air bubble was due to both main and aux tank being empty at pix taking time. I wanted to test to see if bubble would be fully pushed out (up to main) under conditions of empty main, full aux. It did. I didn't need to thump the line or anything, just turn the aux valve on and away it went. Just part of the testing process.
The routing is still a work in process, not finalized yet - although I've had roughly this routing for all of 2 days and 110 miles.. :lol: so by CBA terms, it's damn near certified! :exhappysmiley:

 

[Udjeni]

OK, kink might not have been the right word, but the right one escapes me now (English not being my mother tongue). Bobble? Whatever. Anyway, the only reason I mentioned it is because the fuel line from my aux tank had a similar bobble which, is my theory at this point, caused the flow sometimes to stop. Why only sometimes, I don't know, but it is the only explanation I have at this point. Maybe some day I'll take pictures of the routing and ask people here for their theory. In the mean time, feel free to ignore my theory as unsubstantiated and probably flase.

 

[RenoJohn]

The air bubble was due ........

I bet most of us would see an occassional air bubble in our lines if we were had that clear plastic crap AND were anal enough to go lookin'
Me says: change out the cute clear stuff to real fuel line, button it up and go play moto-bike, get back to twistin' the throttle. You can always burp the line with a good wheelie.

A fuel cel is like a good buddy, takes a while to get to know each other, and that will come with miles. In 35Kmiles you might make a change or two, and you'll have adjusted to any minor traits that your particular cel may have. I think any design is going to have it's own little traits.

And that goes for when you want to throw the valve .....not only the mechanics of how your cel works, but also your own methodologies.

If I'm in rally mode and have many miles ahead, I throw the valve at when the tank is about 2/3 and forgot about it.

If I know I'll be topping off before needing aux fuel, I won't throw it as to not have to dick with two tanks at the pump.

If I'm going off road, I'll throw it early as to get fuel low and forward ASAP.

If I'm on rolling up/down hills I'll throw it early and drain about 1/2 gallon ..as hills cause gas to push on the vent line in my old design when full.

...and the "IF's" for you will be specific to you, your cel and your wants/needs, they won't come from a moto-bike forum.

Enjoy your new riding buddy, you'll get to know each other well in the coming miles.