Dyna\FXR fuel tanks : V-Twin Forum: Harley Davidson Forums

lucille · 05-30-2009, 10:38 PM

Friend took a slider on his '91 FXRS Lowrider the other night, he's OK - bit of rash, but his scoot will need a tank, bars etc.
Question; Have any of you used a 4.9 gallon Dyna Lowrider tank on an FXR?
He's a welder and would cut the rear mounting tab off the FXR tank to go on the Dyna tank.
Forsee any problems?
Appreciate any input, thank you,...Greg

springer- · 05-30-2009, 10:59 PM

The underside rear of the tanks are completely different and the Dyna tank will not fit on the FXR frame. You have to cut the bottom of the FXR and Dyna tanks off and weld the FXR one to the Dyna tank. Then custom fit it. It will be a good project.

Bullwinkle · 06-05-2009, 10:54 AM

>>Question; Have any of you used a 4.9 gallon Dyna Lowrider tank on an FXR?<<

I have one with gas gauge if anyone wants to buy it.

IMO on an FXR it isn't worth the trouble. By the time you notch the rear of the tank to fit the flare of the frame you've lost some capacity, a big reason for doing this. Then you still need to build and weld on brackets.

A -much- easier way is to use an Electraglide gas tank. It is already flared at the rear and only needs the proper brackets welded on, an easy job. If you get the right EG tank, the rear is shaped such that it wraps around the front of the seat and gives it a nice look.

I did exactly this on my FXR and am satisfied at how easy it was and with the extra range. I have pictures, but am not a paid member so I can't post them. If anyone wants them, PM with an email address, or if a paid member wants, I cam email them to him and he can post them.

lucille · 06-05-2009, 09:18 PM

Hi Bullwinkle,
Sent an e-mail address your way. Wish to thank you for your input, Greg

93 FXR · 06-06-2009, 08:46 AM

Thanks very much, Bullwinkle. Much appreciated.

Here's a copy of his response.....

The EG tank on the FXR is easy. You need to build and weld (easy) brackets to the existing EG tank brackets.

All you need on the back bracket is a T strap welded across it with holes corresponding to the FXR bolt holes.

On the front the existing brackets need to be extended and holes drilled in the extensions so the tank is where you want it. I raised the tank a little to accomodate some wires running under it. I think the tank is about 5/8" to 3/4" off the frame rail.

The EG tank channel is wider than the FXR frame, so you can use rubber shock absorber bushings from an auto parts house for spacers. Or get trick if you have a lathe, and make some.

The EG petcock locations are different. On one I have it is about halfway to the front of the tank and on the other it is about where the stock FXR petcock is. No big deal other than dealing with force of habit.

I don't have any pictures of the underside of the tank, but the EG tank fits like it was made to go there.

If you can link to them on the forum, it might be a help to others. This comes up every now and again.

I'll have a second post with different pictures of an EG tank on another bike. It will come later after I figure out how to drop the resolution enough to make uploading and downloading faster.

Hope this helps and if you have any questions, just drop a line.

Bullwinkle

and the photos he sent me...thanks again...

lucille · 06-06-2009, 10:42 AM

Thanks for posting Bullwinkle's photos Paul, I didn't know how to do it...

93 FXR · 06-06-2009, 10:49 AM

Quote:

Originally Posted by lucille

Thanks for posting Bullwinkle's photos Paul, I didn't know how to do it...

No problem, my friend...
Hope this helps your buddy out...at least an option.
Glad to hear he's ok...
Let us know how it turns out, and what he decided to do.....

Paul

Bullwinkle · 06-06-2009, 04:41 PM

The tank swap itself was very easy. It has some benefits that I had not foreseen. The throttle cables now have more room and don't get pinched if I'm not careful when I work on the carb or have the tank off. There's more room between the tank and the frame backbone for wiring. I have a GPS and electric jacket liner and gloves, and running the wires for them is much easier and no worries about them getting pinched. I raised the tank off the frame backbone a little and this gives more room to work on the engine before the tank has to come off.

I was a little concerned that the extra width of the EG tank tunnel would be noticeable, but it isn't.

The only thing is that some EG gas tanks have the petcock about midway forward and it takes some getting used to. No big deal. Someday I'll find a decent leather pouch for sunglasses that goes in the empty space between the back end of the tank console and the front of the seat.

Bullwinkle · 06-06-2009, 04:50 PM

One thing I didn't think to mention is that the tanks I used are from the early to mid 1990s. I imagine that from the mid 1980s would work, too, but not sure about anything after about 1996-2000.

Homesick · 06-06-2009, 08:15 PM

This sounds like the simpler and easier method but, what the he!!, here's another to consider. Widen your FXR tank.

If I remember right, Pilgrim added 2 gallons to his by cutting the tank, longitudinally, on both sides of the frame, and then welding in 2" wide strips. I think he describes the process at wildwestcyclesDOTcom.

joe

Bullwinkle · 06-08-2009, 10:53 AM

If you can weld sheet metal or know someone who can, this is a good way.

Paying someone is not an option. I read an article about someone who was doing this and the price was over $1K. Might as well get a custom company to build one from scratch.

lucille · 11-12-2009, 08:36 PM

Quote:

Originally Posted by Bullwinkle

>>Question; Have any of you used a 4.9 gallon Dyna Lowrider tank on an FXR?<<

I have one with gas gauge if anyone wants to buy it.

IMO on an FXR it isn't worth the trouble. By the time you notch the rear of the tank to fit the flare of the frame you've lost some capacity, a big reason for doing this. Then you still need to build and weld on brackets.

A -much- easier way is to use an Electraglide gas tank. It is already flared at the rear and only needs the proper brackets welded on, an easy job. If you get the right EG tank, the rear is shaped such that it wraps around the front of the seat and gives it a nice look.

I did exactly this on my FXR and am satisfied at how easy it was and with the extra range. I have pictures, but am not a paid member so I can't post them. If anyone wants them, PM with an email address, or if a paid member wants, I cam email them to him and he can post them.

This may help GasCan