R1100S fuel tank capacity.

[S.Baldric]

Greetings, all.

Longtime BMW fan, recent R1100S convert.

Looking under the fuel tank of my '99 non-ABS bike, I see a lot of empty space just crying out to be filled with extra fuel. I seem to recall one poster mentioning a modification to increase the fuel capacity by utilising this space.

Has anyone done a mod in this regard? If so, was it accomplished by cutting the saddle of the tank and welding in a lower replacement, or was a separate tank plumbed in in this area. I could engineer something myself but if someone has tried it before....

Thanks in advance.

[Ciocc]

Uh oh. Flame on.

- Has anyone done a mod in this regard? Yes.
- If so, was it accomplished by cutting the saddle of the tank and welding in a lower replacement, or was a separate tank plumbed in in this area? Yes (to both)

Now off to the search function.

(Time passes...)

OK, I'm back. Try this thread. It describes the tank mod, the fuel neck mod, and has a link to the auxiliary tank mod.

increasing tank capacity

Ciocc

[WandererR11S]

Ciocc,

Thank you... I am also looking for this mod...

[pmc847]

Aux Fuel Tank

Here you go.

Check out post 62. It will show how to increase the stock tank by almost 1/2 gallon just by removing the black plastic float, bent the copper tube up so it almost touches the top of the tank and drill holes in the filler neck.

Philip

[S.Baldric]

Thank you gentlemen! Have to say I like the idea of the aux tank. I'll put up a post if I end up doing a mod.

[bradzdotcom]

there's always empty soda bottles.
i'm personally drawn to the liter size.
for the meager investment of a few yards of duct tape and the consumption of some cherry coke zero, you can easily strap four, maybe five of them around your back.

only drawback....don't ride too close to government buildings or international airports.
apparently it draws their attention.
no idea why, but jeez, do those guys get upset!

i've found that you can also extend tank range (if you're in that mood) by exercising your right to use your lefts.
when i short shift the thing, and keep it below about 4,500 it goes farther. requires more left foot dancing and left hand haggling, but it pays off.
i have one route i do every couple of weeks. on a normal happy throttle day, the reserve light comes on 10 miles before home base.
when i short shift the thing, the reserve light doesn't come on and i have about 10 miles left before it starts winking at me. not a whole lot of extra miles, but can help in a pinch.

that motor is just a pretty looking pump. it pumps air and fuel, swirls it into a fog and spits it out. more happy wrist, more rpm, more air, more fuel....it's a conspiracy.

also wonder why you want to go even farther before getting off and shuffling the deck.

did you drive a tractor with a steel seat in a former life?

[pmc847]

Baldric

Send me your direct email and I'll send you drawings and pics of the aux tank.

Philip

pmc847@tds.net

[ATA]

Originally Posted by pmc847

Baldric

Send me your direct email and I'll send you drawings and pics of the aux tank.

Philip

pmc847@tds.net

Can I have it too!
alvy@email.com
Just for consideration, a bit worried to do it myself, but might!
Thanks!

[S.Baldric]

Bradz, I know what you mean about soda bottles near the airport. A photoshoot with scantily clad young ladies beside the perimeter fence also gets their attention, though in that instance the response was more supervision than shooing away :0P. In your situation perhaps one of those mountain bike water rucksacks could be modified, would garner less attention, though it would be a bit more spendy and less enviro than recycling pop bottles!

I tend to go easy on the throttle usually, partly due to the Gestapo up here being rather keen. And I usually look for fuel around the 200km mark for a leg stretch anyway, but sometimes there's a long way between fuel stops in parts of Canada, and I'm planning a long postponed cross-country ride for next year.

And yes, good call on steel-seated tractor. And worse! Most airplane mechanics have strong masochistic tendencies IMHO.

Another explanation for the mod is the three most useless things in aviation. A foot of altitude above you, a foot of runway behind you, and a pound of fuel left in the tanker. :0)

[bykemike]

I was all wrapped up about this issue when I got my first "S", only natural coming from a KLR and then a GS Adv. As time progressed (ok, I got older) it seems to be less of an issue. Last summer I did the stretch from Taos NM to Durango through that empty, empty desert road and on a Sunday to boot (some of the stations were closed) and made it OK, got a little tense for a while.
I just pulled the low RPM hypermileing trick and had more fuel left than I would have thought.

I find I can ride longer distances with my S than my GS because I have to stop more often, counterintuitive perhaps but it works for me.

Also I have an ABS bike and I think the extra tank thing goes where the ABS unit is.

Mike

[WandererR11S]

Hi all,

Whats the black plastic float thing inside the main fuel tank..? I see mention of remove and discard in the Aux fuel cell thread, also i assume the fuel pump is inside the main tank, could that be taken out, and another pump used in its place, making more capacity in the factory tank...

Jeremy

[sgoodwin]

It's called the black kadork thing & this is it's extrication......The Black KaDork Thing in the Fuel Tank?