Enlarging my fuel tank

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Use a Texas Catheter draining into a leg bag. Done all the time.

Yes, I know of the TC's, just haven't gone to one yet...

 
I made some additional progress today. Finished welding up the front then made a template for the right side that needed a filler:

P1000551.jpg


Transferred to metal and carefully trimmed to fit.

P1000552.jpg


 
Looking good!

I hope you are documenting what you are doing and stocking excess steel and welding materials... I can see many orders starting to line up.

-BD

 
Darn it! A whole day and no update?!? Some of us are really impatient!

Or, maybe just too excited to see the results. :ermm:

 
I am considering the same thing, But I am just going up in the center to get about 1-1.5 gallons. I have a 300 mile butt anyhow. I like to take a guick break every 300 miles of so. The huge tank is the only thing I miss about my 02 connie 280 before I had to stop for fuel, about 300 if you ran well into reserve.

 
My approach would be: Find a bigger tank off something else and try to make it work. I'd wind up with bungees and duct tape, baling twine, lines running everywhere... It would look like **** and work not much better. Or I'd hire someone like Alex.

 
This whole thing looks dangerous to me.

Why would anyone want to carry extra fuel anyway?

:rolleyes:

Keep the updates coming Alex.

 
Do it in a reproducable way. Haunt scrap yards for old tanks. Mod and sell them to those who understand it's better to be in BFE with too much fuel than not enough.

 
I don't think $300 would cover it. Assume the fabricator has only 6 hours in a standardized version (which might be low by a lot!) and you're already at $300 just for labor at a cheap ($50/hr) rate without painting.

My guess is a custom fabbed item like this would cost something more like $700 - $1000; probably still worth the money done right with an OEM quality paint job.

 
I wonder how much my range would increase if I just lost 40 pounds. :assassin:
It wouldn't affect fuel consumption at all at steady cruising speeds. When maintaining speed, the engine only needs to fight against drive-train friction and air resistance, of which neither depend on weight.

A change in weight would only affect acceleration. If you lost weight and reduced throttle input to achieve the same acceleration as before losing weight, then you would use less fuel while accelerating. OTOH, engine braking would slow you down quicker, so you'd either need to wait longer before you start slowing down (using more fuel), or keep the throttle open a bit more (using more fuel) to slow down at the same rate as before you lost weight. Maybe it would all even out to no net change in fuel consumption? It's hard to say how it would all work out in the end. It really depends on how you adjust (or don't adjust) your riding habits.

Probably not the response you expected. Maybe I should've gone the smart-*** route and said something like, "40 pounds? Are you kidding? You'd have to lose a heck of a lot more than that!"

:p

 
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I wonder how much my range would increase if I just lost 40 pounds. :assassin:
It wouldn't affect fuel consumption at all at steady cruising speeds. When maintaining speed, the engine only needs to fight against drive-train friction and air resistance, of which neither depend on weight.

A change in weight would only affect acceleration. If you lost weight and reduced throttle input to achieve the same acceleration as before losing weight, then you would use less fuel while accelerating. OTOH, engine braking would slow you down quicker, so you'd either need to wait longer before you start slowing down (using more fuel), or keep the throttle open a bit more (using more fuel) to slow down at the same rate as before you lost weight. Maybe it would all even out to no net change in fuel consumption? It's hard to say how it would all work out in the end. It really depends on how you adjust (or don't adjust) your riding habits.

Probably not the response you expected. Maybe I should've gone the smart-*** route and said something like, "40 pounds? Are you kidding? You'd have to lose a heck of a lot more than that!"

:p
Not at all. I'm happy. Now I don't have to diet. :yahoo:

Here's a question, though, that's always intrigued me: Does an overdrive give better gas mileage? If it takes a certain amount of energy to push a certain mass through a certain resistance (and it does), then it should take the same energy (and thus the same amount of fuel) regardless of whether I'm in a "normal" fifth gear or an overdrive sixth. The only reason I can think of is that might account for better mileage in sixth is there's more internal friction to overcome at higher engine revs (in fifth).

What do you think?

 
Here's a question, though, that's always intrigued me: Does an overdrive give better gas mileage?
Depends on the torque curve of the engine, and probably other factors that I don't understand.

If it takes a certain amount of energy to push a certain mass through a certain resistance (and it does), then it should take the same energy (and thus the same amount of fuel) regardless of whether I'm in a "normal" fifth gear or an overdrive sixth.
Yes; the same amount of torque at the rear wheel is needed to maintain a given speed no matter what gear you are in. In higher gears, the torque requirement at the crank increases (which means you'll likely have to open the throttle more, but that depends on the torque curve). A higher gear is only more fuel efficient if the engine runs more efficiently enough at the lower RPM and different throttle opening combination to make up for the increased torque requirement, plus some. I believe higher throttle openings often results in more efficient use of fuel because an open throttle creates less turbulence, better mixture of air and fuel, or something similar.

The FJR has a small "bump" in the torque curve between 3k and 4k RPMs; right in the range of 5th gear freeway cruising speeds. I suspect this was intentional to help freeway fuel efficiency.

The only reason I can think of is that might account for better mileage in sixth is there's more internal friction to overcome at higher engine revs (in fifth).
Internal wouldn't change as a direct result of higher RPMs. I think temperature would have the biggest affect on internal friction, but I would imagine the change in friction throughout the normal operating temperature range would be fairly insignificant.

So... speaking of enlarging fuel tanks... any new pics/progress?

 
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