Larger fuel tank for more range?

[FJ_Kevin]

OK... I am looking for some good ideas!

I'm interested in increasing the fuel capacity of my FJ (1986) in order to increase range between refills.

Has anyone run across such a modification? I know I have seen some old BMW's with oversized tanks.
 
I have an old beat up tank to work with and may try to increase capacity by another 1 or 1.5 gallons or so. The low bars pose a bit of a challenge as there is not much clearence to the tank already when against the steering stops. My initial though is to cut along the top of the knee indentations and raise a portion the top of the tank, keeping in mind the clearance needed for the bars. I would fab some sheet metal filler strips to fill gaps that result from lifting the top.  I think I could raise the full length of the top but would have to work in some scallops for bar and hand clearance.  I know it would compromise the FJ looks but I will still have my stock tank and just use this one when I want more range.

The FJ is such a great tourer it seems someone must have already tried this.  I wouldn't mind leveraging someone elses successes and/or mistakes! Any comments, thoughts, ideas?

Thanks,
Kevin

[pdxfj]

There has been one person who attached a fuel cell to the rear of his bike.  I don't remember all the details but I think it was around 5 gallons.  There are companies who make fuel cells for bikes and hooking it into the fuel system wouldn't be too difficult.

[fj1289]

Easiest is an 84/85 FJ1100 tank.  The 1100 tanks are 6.5 gal -vs- 5.8 gal.  Not quite a gallon increase, but a whole lot easier!  

I've seen a similar project, but don't remember any details.  May have been an XS-650 .

Also, if you have removed your airbox, you might be able to make an auxilary tank similar to the tank Phil Hacker made for his FJ Racer http://www.fjracer.com/#/new-mods-2008/4526801588
My thought would be let the main tank gravity feed into the aux tank, and use a fuel pump (did 86's have pumps?) to push it to the carbs.  

Keep us posted on this project!

[thuber3040]

maybe one of these:

http://www.sampson-sporttouring.com/fuel-cells.html

[Marsh White]

There has been one person who attached a fuel cell to the rear of his bike.  I don't remember all the details but I think it was around 5 gallons.  There are companies who make fuel cells for bikes and hooking it into the fuel system wouldn't be too difficult.

Don't forget to mention how Blair's FJ burned to the ground riding to the rally the year after this photo was taken...seriously - it actually happened....FYI

Just strap a small gas can somewhere and be done with it! 

[Klavdy]

The Fluffer King has the right of it.
Unless you decide otherwise, it is not worth the hassle and expense.
Bliar Leyton's bike burned to a molten pile of slag due to a fuel cell that was, he thought, properly engineered.
Alas.
Plus, unless you're riding across the Siberian Steppe,there's fuel most places these days.
Just buy a small can.

[Dan Filetti]

You think you got it bad...  On the GSXR750, I went through a tank of gas (~4.5 gallons) in 137 miles yesterday...  That's an appalling 30mpg.  I normally get ~38mpg, -guess I've been a bit ham fisted of late...

Dan

[andyb]

Meh, buy a zx9!  I get an average of like 44mpg, but the faster I go, the better it gets!  Got 50mpg from it on an extended high speed blast!

Best way to improve the fuel range on any bike is to have an uncomfortable seat. Then you want to get off every hour or two anyhow.

[Dan Filetti]

I guess it varries bike to bike, my buddy has a '99 zx9 and he gets ~40mpg, and less when he rides with me...

Dan

[andyb]

Different motor, I've got a B2, he's got a C2.  Actually the mileage went down a lot from when I got it, turns out stock jetting and a big full exhaust makes you a touch lean... 

[racerman_27410]

TeeCee made a larger fuel tank by taking two tanks and adding half of one on top of the other.... it looked pretty good considering how large the tank was... still looked stock more or less...... i'll see if he has any details on this mod.


KOokaloo!

[racerman_27410]

Posting a picture of TeeCee's 8 gallon fuel tank

[FJ_Kevin]

Hey... thanks for all the replys and ideas.  

While the extra tank on the passenger seat sounds like a good idea to me, I have a feeling I might have trouble getting my wife to go along with that one...

It actually was interesting to see some of the fuel cell options though, thanks for the links and photos.  I was not aware that the FJ1100 tank holds more fuel than the fj1200 tank, thanks for that tip.  Does anyone know what happened there or where the capacity was lost? The top side of the two tanks look about the same to me.

Racerman: It would be great if you could find a photo of that double tank... this was something I was thinking about also although I only have one beater tank to work with for now.

Thank too for the FJracer link, clever guy with good stuff there.  If do decide to tackle this (likely a winter project), I 'll post some pictures along the way.

Wow the big tank picture just popped up as I was typing this... thanks racerman!

Thanks for all for the inputs...Kevin

[teeeeeceeeee]

Thanks Frank,

It's made with two tanks cut horizontally though the centre, one above the centre line the other below then migged together with a little metal massaging to get the lines to meet.

I ended up with 30 litres or 8 Gallons US an increase of 6 litres or 1.5 Gallons.

I called it a "Half day sucker" in that you could go cruising and only stop for fuel every half day.


Kookaloo

TeeCee

[FJ_Kevin]

Teecee,

I am a little confused about where you made the cuts... by "centre line' are you referring to the painted stripe?  So on one tank you cut along the black and white edge and the other tank you cut along the black and red?  Is that right?

Great job you did there, any clearance issue with the bars when forks are against the stops?

Oh... and why don't you just sell me your tank?

Thanks,
Kevin