Enlarging my fuel tank

[Alex]

I've wanted to add some capacity to my FJR for quite some time and finally think that I've found a good solution. I originally was going to build a fuel cell under a small Pelican case on the rear Givi rack, or a passenger seat tank. Since my wife rides quite a bit with me I've decided against 2nd option. Ever since I saw John Ryan's fuel tank tower, I wanted to get my hands on a spare tank to modify. I thought with a little imagination and time I could add 1.5-3 gallon and keep the lines of the tank looking decent.

My goal is to add around 1.5-3 gallons, just enough to keep up with the range of my brothers GS Adventure. His tank is almost 9 gallons but I get 5-10% better mileage.

I finally found a tank in decent shape from a fellow in CO that was selling his on Ebay. $80 and 2 days later it was on my front porch. I started on this project today, below are pictures of today’s progress.

Tank chemically stripped and carefully sanded (no abrasive sanders were used)

1st cut is to widen the tank about 2 inches total

2nd area for improvement is to raise the entire top about a ½”. This is not much of a change but should help out a fair amount. This is as high as possible and still have a fair amount of clearance for turning.

Next is welding up those first areas then cutting the top off where marked. I will then braise in some new fuel overflow lines and see how tall I can raise this section without really screwing up the looks. I’m estimating around 3”

After all is complete I will use all the proper primers and fill to smooth out edges and then send to Garauld for painting.

Feel free to suggest any changes or areas I need to consider when finishing this tank. I will not be able to work further until Tuesday/Wednesday afternoons. I’m working out of town for a bit.

 

[GalaxyBlue]

I like where this is going! :good:

 

[meosborn]

I like where this is going! :good:

+1

This looks extremely cool.

 

[mjones35]

Wow! You sure are taking on a project. I know I'm new here, but I'm ready for a break by the time my tank is close to empty. Hope you post some pics when its done.

 

[kaitsdad]

I like this !

Please keep us up to date on your progress, and how much additional volume you're able to add.

Way Cool. k:

 

[dcarver]

Another member with mad skilz! :clapping:

 

[Badcat]

I am liking this....keep us posted.

 

[johnny80s]

Very cool Alex.

 

[Alex]

Thanks for the responses. I'll try to keep this project moving along as quickly as possible. I hopefully will be ready to send for paint this time next week. I could have it powder coated at work but I think having it painted to match will be a nice touch.

 

[TruWrecks]

Paint to match would look a lot better. People will notice something is different, but most won't notice what it is.

 

[dsego]

If only I could increase the size of my bladder!

 

[fljab]

If only I could increase the size of my bladder!

That's my problem! I added a 5 gallon Summit cell on my other bike to give 10 gallons total but it was rare that I could use the full range...

 

[Randy]

What is your plan for doing a pressure test to make sure all of the new welds are sealed up tight?

 

[chrisflock]

I think I remember someone on the forum doing a pressure test and deforming their tank...

When you do a test, remember that the tank isn't meant, or rated, to hold any significant amount of pressure!

 

[Alex]

What is your plan for doing a pressure test to make sure all of the new welds are sealed up tight?

I will be using an air pump designed for the inflatable mattresses. Only for the reason mentioned. I don't want to apply too much psi. After low pressure checking it I will follow-up with a tank coating for the entire inside of the tank. This coating isn't cheap, but the new welds should be protected with something to keep them from rusting.

This reminds me of a member that had issues with his tank rusting and clogging up his pump. The inside walls of both of these tanks look factory perfect. I can't even find a hint of rust in the top of the tank. I think when you find rust in your tank sloshing around, it most likely has come from a bad gas.

 

[oldryder]

""I think when you find rust in your tank sloshing around, it most likely has come from a bad gas.

+1

you might want to make an in-line fuel filter part of the project. good insurance and cheap. I got a boatload of rust one time with a fill up. Ended up having the clean the carbs (a 1974 Z1) in a gas station parking lot in the middle of the desert with no shade. not much fun.

 

[Joe2Lmaker]

I think I remember someone on the forum doing a pressure test and deforming their tank...

I remember that too. Warning! <Link>

 

[johnny80s]

Thanks for the responses. I'll try to keep this project moving along as quickly as possible. I hopefully will be ready to send for paint this time next week. I could have it powder coated at work but I think having it painted to match will be a nice touch.

Just cover it with a big sticker. Why paint it?

 

[RadioHowie]

""I think when you find rust in your tank sloshing around, it most likely has come from a bad gas.
+1

you might want to make an in-line fuel filter part of the project. good insurance and cheap. I got a boatload of rust one time with a fill up. Ended up having the clean the carbs (a 1974 Z1) in a gas station parking lot in the middle of the desert with no shade. not much fun.

Problem with the FJR is it's fuel injected, which means any rust in the tank (if there is any) that doesn't plug up the strainer on the bottom of the pump is going to go through the pump, effectively sandblasting the pump housing interior. Before you know it (in my case about 15 miles of riding) the pump is ruined. A filter isn't going to do your pump a lick of good, but will keep your injectors from getting plugged up.