FF: Forks How Much Space Do You Have Between FF3 (Bottom Link) and Gas Tank?

[CarlHungness]

Preparing for my first buck making project to clone my gas tank in aluminum and I noticed my FF3 bottom fork link
is preciously close to the gas tank. There's about 1/4" clearance at best. I have longer springs front and rear, purchased
years back from Justin MacKay Smith and feel confident this change has brought the gas tank so ultra-close to the link.
Thus, I'd like to know approximately how much clearance exists on a stock suspension bike. Plus, modified spring
machines would also qualify to give me knowledge.
My worry is I am going to make templates from the outside of the tank of course, and the new tank will be made
from .063" aluminum. I was going to go with .081" but after running some of the thinner stuff through a new friend's
power hammer for a couple of minutes I don't want to tackle anything thicker than 1/16". I'll be using a mallet and
a tree stump so I have enough of a challenge without worrying about material thickness.
Trying to measure the distance from the tank to the link is not easy, so guesstimates are acceptable. Then too,
see if there's much of a change when your machine is on the side stand. Thanks in advance.

 

[oexing]

You are looking for a challenge suppose ? Basically you could have alu tanks from India, in various conditions, painted, chromed, alu, other designs, see links - maybe attractive to other Vincenteers ?

Vic

New Vincent HRD Black Shadow Aluminium Petrol Fuel Tank + Filler Cap & Keys | eBay

Are you restoring your Vincent bike and are looking for this rare to find petrol tank. Then your wait ends here, grab this reproduction tank. The above shown tank is made from ALUMINIUM. These can also be fitted on other british bikes too.

www.ebay.co.uk

Vincent HRD Legierung Aluminium poliert Gas Kraftstoff Benzintank mit Knieschütz | eBay

Hier ist derVincent HRD Legierung Aluminium poliert Gas Kraftstoff Benzintank mit Knieschütz erhältlich mit bester Qualität und bester Übereinstimmung. Dieser wurde aus 14 Gauge schwerem Aluminium gefertigt und verleiht dem Tank ein sehr schönes Aussehen.

www.ebay.de

 

[CarlHungness]

You are looking for a challenge suppose ? Basically you could have alu tanks from India, in various conditions, painted, chromed, alu, other designs, see links - maybe attractive to other Vincenteers ?

Vic

New Vincent HRD Black Shadow Aluminium Petrol Fuel Tank + Filler Cap & Keys | eBay

Are you restoring your Vincent bike and are looking for this rare to find petrol tank. Then your wait ends here, grab this reproduction tank. The above shown tank is made from ALUMINIUM. These can also be fitted on other british bikes too.

www.ebay.co.uk

Vincent HRD Legierung Aluminium poliert Gas Kraftstoff Benzintank mit Knieschütz | eBay

Hier ist derVincent HRD Legierung Aluminium poliert Gas Kraftstoff Benzintank mit Knieschütz erhältlich mit bester Qualität und bester Übereinstimmung. Dieser wurde aus 14 Gauge schwerem Aluminium gefertigt und verleiht dem Tank ein sehr schönes Aussehen.

www.ebay.de

HI: I want to make my own tank first. Then hope to progress to larger more
complex items. The idea is to learn to make the aluminum go into a compound shape of my desire. I'm most familiar with the tanks from India selling for virtual pennies. They are stamping them. I have a tree stump that will serve my apprenticeship well in trying to clone the tank, hoping my somewhat duff right thumb can stand the pounding. I'm getting my first tank of hydrogen next week to start oxy-welding the material. I recall the day when I made my first violin maker's knife and used it to carve my initial violin. So, you're right, it's a new journey.

 

[Chris Launders]

Carl, with the JE stem the distance is just over 3/4", this is because it basically lowers the bottom link pivot that sort of distance.

Why would springs make any difference, the tank mounting is to the rear of the eccentric, any movement of the link is rotational, and the link "arm" is to the front.

I doesn't matter what springs you have, max up and down are the same as this is limited by the damper.

 

[Chris Launders]

Carl, one thing to watch when making your tank, a friend who is an armourer has just made a suit of armour in aluminium and says the hardest bit was the helmet.
Not being as strong as steel once he got say one side right, doing any work on the other pulled the one he had already finished, so he had to constantly keep going backwards and forwards all the time, and actually took much more time than a steel one.

 

[davidd]

I used steel to make my first racing tank. I used aluminum-killed (deoxidized) steel as I was using a hammer, slapper, and a shot bag to form the tank. I did have to make smaller pieces to form the tank. I don't think aluminum is suitable for a Vincent tank unless the material is very thick.

David Tompkins used an aluminum tank on his racer, against my advice, and I believe it needed to be patched every other race. If the mounting is done very carefully with aluminum in mind, and the aluminum is thick enough, like a Paul Adams tank, it will work. Aluminum tanks do well if they are strapped on with no mounting bolts.

David

 

[CarlHungness]

Carl, with the JE stem the distance is just over 3/4", this is because it basically lowers the bottom link pivot that sort of distance.

Why would springs make any difference, the tank mounting is to the rear of the eccentric, any movement of the link is rotational, and the link "arm" is to the front.

I doesn't matter what springs you have, max up and down are the same as this is limited by the damper.

I need some geometry knowledge then. As is, my link is ever so close to the tank. Does my 21" front wheel figure into the equation?

 

[CarlHungness]

I've seen many videos on motorcycle tank construction, so am pretty familiar with their construction, but that still doesn't tell me where I need to start beating. I am going to spend a lot of hours making a buck initially and will then get out the shot bag, stump and hammers. Now, I'm getting my first hydrogen tank as I have to hone my aluminum welding skills using the hydro and oxygen. My initial plan was to use .063" aluminum and clone the existing tank. What thickness steel did you use for your tank? Mine will be three pieces, two sides and a top as far as I can see. It will be several months before I start as I'm finishing restoration of my 1937 LaSalle and have a sculpture to do of a violin maker presenting a new instrument. I'm 3-D printing my own 1707 Strad copy so I don't have to carve a quarter scale violin. Would like to know the precise steel designation you used too if you can recall what it was.

I used steel to make my first racing tank. I used aluminum-killed (deoxidized) steel as I was using a hammer, slapper, and a shot bag to form the tank. I did have to make smaller pieces to form the tank. I don't think aluminum is suitable for a Vincent tank unless the material is very thick.

David Tompkins used an aluminum tank on his racer, against my advice, and I believe it needed to be patched every other race. If the mounting is done very carefully with aluminum in mind, and the aluminum is thick enough, like a Paul Adams tank, it will work. Aluminum tanks do well if they are strapped on with no mounting bolts.

David

 

[CarlHungness]

Carl, one thing to watch when making your tank, a friend who is an armourer has just made a suit of armour in aluminium and says the hardest bit was the helmet.
Not being as strong as steel once he got say one side right, doing any work on the other pulled the one he had already finished, so he had to constantly keep going backwards and forwards all the time, and actually took much more time than a steel one.

Making two sides match is a challenge in everything from clay to steel to aluminum. That's why I'll make a precise buck, make one side then the other, then the center. It'll be a long challenging road and that's why I'm doing it.

 

[vibrac]

I am a bit lost on the original question
1/4 clearance?