DaJuice and Cruzin need a fuel cell

[DaJuice]

Cruzin and I have identical steeds, 2008 FJR1300A's with a Givi V46 mounted on the Givi bracket. We have both decided to add fuel cells this winter and figured we'd just team up and build two (or more). I've been scouring the net and talking to a few others and have started a blog page to house the info I'm finding. I wanted to put a thread up on this site to get as many comments and criticisms as possible. My idea is we can discuss here and I'll be feeding all the info to the blog to keep everything organized. I also need to give a big thanks to one of those ST1300 types, STRich, as he is willing to help us with the ideas and fabrication of our cells (and he is looking at building a Tanji clone and adapting it to his ST this winter).

Link to the blog page

From rallying we've seen a couple cells on some GenI FJR's in the area (Behmer and stryg8r). Behmer has a 4 gallon RCI cell (Identical to the 4 gallon Jaz) and stryg8r has one of the elusive Tanji's. They were willing to let of have their cells for the winter to get ideas. I picked up Behmers RCI last week and was amazed to see the difference between the GenI and GenII under the seat.

Here is the cell on Behmer's GenI bike

Here it is on my GenII bike (Just propped up)

Notice how much narrower the opening of the plastic is on the GenII than the GenI under the seat. The mounting leg on the front of the cell comes down outside the opening of the plastic on the GenII.

I had printed some photos of my bike with the seat removed when I went to look at Behmers and we noticed some radical differences in the design between the two. We took some photos of both bikes with a tape measure starting at the rear of the tank for a reference.

GenI top view with no seats

GenII top view with no seats

We have not committed to a design. Initially I wanted to do this the easy way since I really need a cell for next year and just get the Jaz 4 gallon or one of its clones. The problem with that cell is That only gives a total fuel cap of 10.6 gallons. I'd rather have a cell with a cap closer to the 4.8 gallon mark to get me just under the IBR cap of 11.5 but that is going to cost more money. I am looking for a Pillion mounted system currently that I can easily remove as I don't want to have the cell on all the time.

None of the off-the-self units for the FJR seem to fit the bill due to my setup. IIRC the sidebags on the GenII protrude less from the center of the bike but I believe the sidebags themselves are identical to the GenI. I’m assuming this is why the area under the seat is so much narrower. The Sampson design will interfere with my top case on the Givi Bracket. Yes I know, there are alternatives to the Givi bracket but I’d prefer to make what I have work.

I noticed Warchild's post and if I go the route of designing and building my own I really like that design as I can adjust the dims to fit inside the narrower Givi bracket on the GenII and reposition the front brackets to mount to what I'm thinking is the cross bar that holds the passenger seat. I really liked the storage room he had under the cell.

I've been watching 2Lmakers thread too but I'm leaning towards gravity feed at the moment. That thread has been very helpful in collecting info for what I'm looking for though.

All this being said, what does this mighty universe have for comments so far? Has there been anyone else put a pillion mounted fuel cell on a GenII with a Givi V46 with a Givi Bracket?

 

[Joe2Lmaker]

Someone should offer a group buy on these things.

Bionic Pelvis needs one too.

edit: An announcement like that would make a cool 1,500th post for someone.

edit edit: oops! I wouldn't have done that if I'd known that this thread was going to be where DaJuice showcased his tank.

 

[rickcorwn]

Someone should offer a group buy on these things.
Bionic Pelvis needs one too.

edit: An announcement like that would make a cool 1,500th post for someone.

Stop the presses, did he say group buy?? Yes, I am a slow leaner :blink:

 

[JamesK]

I saw what IMHO was the nicest and most functional Gen2 Aux tank yet on a couple of the FJRs attending the 2009 IBR. This cell was custom made originally for B.B. Neely, and subsequently manufactured for another FJR IBR participant. The original cost around $1,000 but from what I was told since the design is already available subsequent units are cheaper, although I have not checked the latest pricing with B.M.W. I imagine we could get a decent price with a group buy setup. I also really like that this design keeps the weight fairly low to the COG of the bike...

Whilst the flush filler hole looks nice, it would make strapping any luggage on top of the cell a PITA to re-fuel, so I would probably consider a side mounted filler neck. Alternately, the design could include a swing out/flip-up shelf that lets you retain the nice flush filler cap since the stuff packed on top of the cell would flip out of the way as it would be secured to the shelf...

Also, given the concave design of the front of the cell a back rest pad could be easily fitted with either velcro or to a couple of mounting points that could be built-in to the surface....

This Aux tank is made by Bennet Machine Works (BMW) in Owasso, OK (918) 636-4570

As you can see this cell fits inside the OEM rack, which is narrower than the Givi rack. I can't quite remember if these were gravity fed or used a fuel pump, but based on the hight it should work either way. My preference would be to use a small, inexpensive generic fuel pump that available in any autoparts store. This cell is obviously IBR compliant, and has built-in baffles.

 

[JamesK]

Joe2Lmaker,That auxiliary tank by Bennett Machine Works really is clean looking. No visible fasteners. No hint as to how to get the front seat off. Quite the puzzle...

Sorry, I forgot to mention, the front seat is removed using a small simple pull cable with a loop on the end that pulls on the front seat latch. The cable is fairly light so pretty much hides under the lip of the front seat when not in use. The aux tank secures to the bolts that hold the rear rack. This is most likely the aux tank I'll by when I have some spare $, I really like it.

 

[JamesK]

As some have probably noticed the top picture (of the original prototype design) of this tank does not have the sloping lip as seen in the other pics. BB Neely told me that B.M.W. added the sloping lip to the design for subsequent units.

 

[DaJuice]

As you can see this cell fits inside the OEM rack, which is narrower than the Givi rack.

Man, I was hoping you were right as that would have meant we could have made a cell work for either bracket. I still had my OEM bracket so I laid it over my Givi. The Givi cuts in sharper than the stock bracket. That is still a good tip on BMW, I'll give them a call and see if they will give me the footprint dimensions to see if it will work or if they'd be willing to trim it a bit to make it work.

In the pic I've got the camera over the left arm of the bracket.

Hey 2Lmaker... is that post being saved for the announcement for the group buy on yours?

 

[JamesK]

Sorry about that, I was sure it was the other way around. But looking at the pic, the cell is narrower than the spacing of the OEM rack so it might still fit :dntknw:

In any case please do post the outcome of your conversation with the B.M.W. guys.

 

[DaJuice]

To help me figure out if I want to go the full custom route or go with something off the shelf I got myself some cardboard. After some measurement and volume calcs I came up with this footprint and cut it out of cardboard. It roughly follows the shape of Warchild's cell, narrower in the back to fit between the givi bracket. The volume would be 4.88 gallons ignoring baffles and wall thicknesses if the cell were made 6.125" high.

I figure this is about 115" of welding by the time I weld the footprint to the sidesheet (which I'll have most of that bent) and put the top on. I figured about 6" worth of welding on the inside for the baffle.

For material, it is looking like most of the off the shelf units are 1/10" thick so I'd use that. I've come up with a surface area of 478 sq inches. I have not looked into the price of aluminum or what size sheets are available, anyone got any advice for me there?

 

[JamesK]

DaJuice, just curious what Bennett Machine Works told about pricing, especially if we did some group buy type of arrangement?

 

[fljab]

DaJuice, just curious what Bennett Machine Works told about pricing, especially if we did some group buy type of arrangement?

I'm interested as well; a fuel cell is "on the list" of mods for my bike.

I really was thinking of the Summit/Jaz/RCI aluminum 4 gallon cell. I too would like to go the max, but the price for the premade 4 gallon is so much cheaper, but still, if a good design can be come up with and we get a decent price for a group buy, I'll look at that.

I do not run a Givi or similar topbox; I was thinking of running mine longways. I figured I would have to cut off 2 of the side tabs (so it doesn't stick in my back), and weld on new ones somewhere else appropriate. I also was thinking of coming up with a way to reasonably quickly get underneath it if I need to get at something. I like the wire pull cord idea for the front seat!

 

[DaJuice]

DaJuice, just curious what Bennett Machine Works told about pricing, especially if we did some group buy type of arrangement?

I didn't try to get a hold of them during the holiday season and this past week at work was crazy so no time to call. I tried to find a website or email address for them but I couldn't. My IT department is taking my laptop Monday morning so I'll be pretty much worthless all day... sounds like a good time to make some personal calls.

 

[DaJuice]

I really was thinking of the Summit/Jaz/RCI aluminum 4 gallon cell. I too would like to go the max, but the price for the premade 4 gallon is so much cheaper, but still, if a good design can be come up with and we get a decent price for a group buy, I'll look at that.

Sounds like you are in the same spot as me. I don't know if you looked at any of the blog linked in my 1st post but I have Behmer's 4 gallon RCI cell in my garage (and stryg8r's Tanji cell at another friends house). The RCI/Jaz/Summit sounds like the cheapest option and I may still go that route. However, there are still a lot of mods I'd want to do to those cells if I went with them. I don't like where the vent is so I'd have to move that, same thing with the outlets, I want my outlet on the bottom so I can get everything out of the cell, the off-the-shelf 4 gallon cells have the outlet fairly high on the back of the cell. By the time I do that I'm going to be adding some non-negligible $ onto the cost of it. It is all going to come down to the financial for me and what makes sense.

I am planning on making my cell to fit with either the stock or Givi Bracket on the GenII. Joe2Lmaker's cell is going to fit both also. We've been talking lately and we both have a niche. What he is designing will be very low and use a pump. What I'm looking for is gravity feed and a storage compartment under the cell for my tools (the storage area is a big CTQ for me). Joe is definitely going to make more than 1. Cruzin and I are teaming up on the cell I'm talking about so we are going to make 2 at least. I'm going to wait and see how much of a headache it is before I decide if I want to make any more but the general consensus is from the people helping me is we might as well.

There are a few more reasons I have not made time to chase down the Bennett cell. 1. My CTQ of storage is not met. 2. I want a filler neck so I don't have to put the bike on the center stand to fill the cell completely. 3. The paint is a very heavy duty rhino lining looking material which makes me question the quality of the welding. I don't know what the Bennett is made out of but normally if you have aluminum with immaculate welding (like the Tanji) you get it annodized. If the welds are good, you powder coat. If the welds are crap... you cover it up with a coating like the one in the pics of the Bennett. I'm not saying they are bad welds, it just makes me question them. If you ever get a chance to see a Tanji close up, look at the welds, they are a piece of art - Kudos to the person that did that.

 

[JamesK]

....There are a few more reasons I have not made time to chase down the Bennett cell. 1. My CTQ of storage is not met. 2. I want a filler neck so I don't have to put the bike on the center stand to fill the cell completely. 3. The paint is a very heavy duty rhino lining looking material which makes me question the quality of the welding. I don't know what the Bennett is made out of but normally if you have aluminum with immaculate welding (like the Tanji) you get it annodized. If the welds are good, you powder coat. If the welds are crap... you cover it up with a coating like the one in the pics of the Bennett. I'm not saying they are bad welds, it just makes me question them. If you ever get a chance to see a Tanji close up, look at the welds, they are a piece of art - Kudos to the person that did that.

Just for the record, one of the guys who's B.M.W. tank is in my pictures told me that he'd done/requested the Rhino coating because he likes it and that the cell was made out of aluminum. I don't know if this was because of ugly welds as you suspect or not...

The filler neck can be mounted on the side, but I imagine there might be some small cost for that.

In any case I'm closely watching this thread since I'm in the market for an aux cell too, but for me the extra bit of storage under the cell is not a deal breaker, I'm happy with the space currently available with the rear seat.

 

[fljab]

I don't know what the Bennett is made out of but normally if you have aluminum with immaculate welding (like the Tanji) you get it annodized. If the welds are good, you powder coat. If the welds are crap... you cover it up with a coating like the one in the pics of the Bennett. I'm not saying they are bad welds, it just makes me question them. If you ever get a chance to see a Tanji close up, look at the welds, they are a piece of art - Kudos to the person that did that.

I was planning on doing an overlay, something like a custom tank bag https://www.customtankbags.com/ These aren't cheap either but they are a nice setup and can be done anyway you want; plus once it's done, it will last the life of the bike/aux tank.

If I do it longways (well, regardless of the layout) I was planning on also using the tank as a backrest as well. We get this "elephant hide" we use at work for kneeling when working on things, so a chunk of that either single or double thick ought to do the trick I think.

Yes, modifying the stock off the shelf tank could bring the price up to where if we get a good deal on a group buy it may be worth doing that instead, but I think you could fabricate many things and just have the welding done and still keep the price at less than half of a custom tank; question is, what's that extra ~.8 gallon worth to ya? Alot if it's 0300 in the rain in the middle of the desert, but not so much if you just plan things ~35 miles sooner. 10.6 gallons still will get you to 400 miles or thereabouts but, yes, per IBA rules you can get a little bit more.

 

[Warchild]

Gentlemen, allow me to put on my IBR Technical Inspector's hat for a moment, and offer a comment for your consideration. If you never intend to enter the IBR or any sanctioned Endurance rally that adheres to the standard 11.50 gallon total capacity, you are certainly free to ignore the following comments.

I do not, in any way, shape or form, advise y'all to build a cell that pushes the 11.50 capacity to the n-th degree. Building a cell that holds a maximum of 4.80000 gallons is MORE than sufficient (believe me - TRUST me), and gives the rider a total of 11.4 gallons of capacity BEFORE fuel lines and filters are taken into consideration. A typical 5/16 or 3/8 fuel line (I.D.) that is roughly 4-ish feet in length, coupled with a relatively small in-line fuel filter, should not push that final .1 gallon issue that much, and more importantly, should not raise the eyebrow of Mr. Tom Austin and make him feel inclined to subject you to the dreaded Fuel Capacity Measurement test. This is about the last thing that an already stressed out IBR rider wants or needs during IBR Tech Inspection. Believe what I say, gentlemen.

Again, if you never intend to go rallying with your cell, then the above comments are not germane to you.

However, if you *think* you might want to dip a toe in the Endurance Rally waters, be mindful of this advice.

And don't forget to heed the requirements for baffling and venting in your design. Folks have failed Tech Inspection before for these items.

 

[DaJuice]

However, if you *think* you might want to dip a toe in the Endurance Rally waters, be mindful of this advice.

I was hoping this thread would catch your eye as I'm building this for the IB5K. I'm using this thread and accompanying blog to document my build for you to offer any feedback per your suggestion - I could do without any surprises at the starting line. My plan is to have my cell be 4.8 gallons when I'm said and done. The 4.88 gallon I mentioned above was ignoring the thickness of the aluminum and assuming the cell would be 6.125" high. Once I get the external dimensions figured out I was going to trim the height to get the correct volume.

 

[DaJuice]

...question is, what's that extra ~.8 gallon worth to ya...

Exactly, Cruzin and I are designing what we want, if it is going to cost an extra $500 to get that extra .8 gallons then my bike will have an RCI on it.

 

[Warchild]

question is, what's that extra ~.8 gallon worth to ya?

I'll ASSume you actually mean "is that extra ~.08 gallon worth to ya?"

4.80 gals -- good

4.88 gals -- a visit by Mr. Tom Austin