F3 tank with stock seat?

[ekubota]

I've just bought an F3 tank to replace the stock one... all of the information I've seen relates to using this with a Monster seat.

Can I use it with the stock seat/rear cowl? What are some other mounting options, preferably with as simple fabrication as possible? I want to keep the stock subframe (if possible) as well as the stock plastic inner fender/battery box.

[VWTim]

I'm using mine with a stock seat. Bows out the front a little bit and the lines don't match perfectly. But it's a daily rider, not a show bike. I do have another seat pan that's been molded and cut some to fit better I want to get repadded and covered.

[ekubota]

Great... I also came across this link: http://www.wildnkrazed.com/BDTech/Tank.html

which shows a trimmed stock seat that looks fine.

Other questions - is extending the front tab really necessary? What's the best place to find a welder/fabricator if necessary?

And what petcock will fit with enough space between the rear valve cover?

[VWTim]

Well, my mounting isn't quite as elagent as BD's. I cut down the rear tab of the F2 tank as far as it could go and still have an 8mm bolt thru it. I then just space the tank up with a piece of rubber for vibration and use a Delrin bushing I had lying around, ~1.5" Then I use a rubber grommet and a 6mm bolt and nut, and bolt it on top of the frame up front.

As for a petcock I'm using a Pingle unit and also cut down the petcock tube as far as I could and still get full thread engagement. This was nessesary with my mounting to clear the rear valve cover. I also had a Harley petcock that i'm pretty sure would fit.

[ekubota]

Did you have to replace the stock airbox to make room for the new tank? Also, which Pingel unit did you use? Is it really smaller than the stock one? (I found a post on the listserv indicating that the size difference was marginal)

[VWTim]

Did you have to replace the stock airbox to make room for the new tank? Also, which Pingel unit did you use? Is it really smaller than the stock one? (I found a post on the listserv indicating that the size difference was marginal)

Size different vs which? The Pingle was nice as it has a horizontal outlet. As to the airbox I'm not sure as I have Uni Pod filters installed.

[ekubota]

vs. the stock petcock, which is apparently too large to clear the valve cover on the F2/F3 tank.

Horizontal outlet would be nice but I'm really trying to find a way to avoid spending $65 on a petcock.

[incogbdog]

I have a F2 tank on my bike. Hopefully this will help you some. I'm using a Hyper Form sub frame and tail on my bike though... Now keep in mind, I'm limited to the common mans tools here.

First I heated up and bent my petcock outlet towards the back of the bike for the correct clearance (valve cover) that I needed. After bending it, I had to fill in a hairline crack just around the base w/ a little bit of brass. I could have avoided this if I would have heated it up a little longer before bending it.

Here is a picture with the stock F2 petcock screwed into it. I'm using the stock F2 petcock w/out the big plastic knob that screws into it from the factory. Anytime that I need to turn the gas to the off position I just use a small wrench on the petcock instead.

As for the front tab, I just cut the factory tab off. Then I welded a small piece of flat steel that I picked up at Home Depot on to it and drilled a hole into the end of it. The piece of steel that I used was about 1 1/2 inches longer than the stock tab. It took a little bending to get it right but no big deal. I'm even using the stock hawk rubber piece on the end of the tab.


Here it is on the bike.

To mount the back end of the tank, I just used a block of wood (yes, wood) that is about 2 inches high by 3 inches square. I painted it black and used a long bolt that runs through the tank then the block of wood and bolts to the sub frame. I know that this sounds kina ghetto, but it actually works really well and I was able to use the stock Hawk rubber piece on the back end of the tank as well. The F2 petcock has just enough clearance over the rear valve cover. Again, keep in mind I'm using the Hyper Form sub frame.

Hyper Form: http://www.hiperform.com/new_page_3.htm

[ekubota]

Does the F2 petcock fit the F3 tank? is there anything that will fit without bending the outlet?

Also, there are two nipples on the bottom of the F3 tank. One is clearly for fuel overflow, but which one, and what is the other one for?

I did a test fit of the tank. It definitely won't fit with the stock airbox, even with lid removed. Also, the front tab will need to be modified as you describe. Any good place to have welding done? How did you remove the original tab?

Also, did you have to modify the rear tab?

What about removing the bracket under the rear of the tank that holds a relay and various wires/tubes? This seemed to get in the way on my bike. Also, I'm not sure the seat would fit even if the tank were mounted - it's too small in the front to go around the F3 tank and seems like it can't be pressed down enough to engage the tab on the bottom.

This is somewhat frustrating. If I go ahead with the project I will order the uni pod filters and replacement jets, but I'm not sure how/where to have the fabrication done.

[ekubota]

Another question - I read that the F2/F3 petcock needs vacuum to supply fuel. Did you run a line from somewhere, or what?

[VWTim]

Couple quick answers, the F2 and F2 petcock should be the same as the tanks are the same. I'll try to snap a couple pics of mine, but I don't have a good camera. I did mine wihtout any welding, just cutting.

[ghandi1616]

Two questions for the F3 tank:
1. I know that Harley petcocks work. What year? Thread size? Angle?
2. I have recently found out that the venting of the tank requires a hole drilled in to the cap. Where is this drilled, and what size of hole?

Now that I think about it, is seems like multiple questions. Also, any pics would be appreciated.