A call for a modern petrol tank

[Panama]

Why can't someone make (for a reasonable price) a reproduction petrol tank that wont rust or split.
My Rapide has a leak at the rear mount, in exactly the same place that my Shadow leaked many many years ago. I read about how well engineered the tanks were, but leaking in this location seems to be a common problem, along with rusting.

With the modern space age materials available, it should not be difficult to produce a tank that looks in every way just like the original, but without the problems.

If available, I would get one, have my original tank fixed and put it away in the event that I sell and the new owner wants to go 'all original'. They make entire Corvettes out of plastic. Can't some clever soul produce one from carbon fiber or some other space age miracle material.

 

[chankly bore]

It should not be beyond the bounds of possibility to do something a) reasonably pretty b) of greater capacity and c) of good quality steel or aluminium alloy. Some years ago some clever fellow showed me the bottom plates of the tank he had reproduced exactly. I believe he was in eastern or southern United States. Does this jingle any faint bells with any readers? I have NEVER seen an Indian-made tank that fits first time and/or doesn't leak! As usual I await contradiction, contraception or excruciating verbal laceration.

 

[vibrac]

The key phrase is in brackets in the first entry
"for a reasonable price"

Ah! what is reasonable?

 

[Ken Tidswell]

The Spares Company were going to have some larger capacity tanks made in steel but the demand at that time was too low.
Hand laid up tanks of organic material will always be economic in small numbers.The late Phil Primmer proved that , he never charged enough and came up against the ethanol problem, which can now be overcome. To repair a steel tank means you have to get it steam cleaned, then welded . Then repainted.Where the industrial base has been eroded finding some one to gas weld a tank may be difficult.Aluminium tanks of greater capacity are available in the UK but the maker never advertises the fact, like lots of things connected with Vins. I don't know who he is.

 

[vibrac]

I had luck with my alloy tank. the main top piece (where the labor costs reside ) came as an alloy 'cover' on a steel tank I purchased. someone with clearly some skill on an English wheel or a lot of patience with a hide mallet had used a standard tank as a 'last' the alloy cover went on and off with a slight spring then it was an easy job for an alloy base and oil tube to be added at a reasonable cost. With alloy I felt a sensible way of fixing was pushing the tank on to a rubber covered UFM and using the back fixings as studs with R clips and the front as simple holding down points this was the best way as the tank is often off and on in racing (in any case I have a B***y great hole on top to get the carb in).For road use I am sure the standard fixing method would work and look correct but a vigilant vibration watch would be recommended

 

[redbloke1956]

Can anyone tell me why our tanks tend to split? Also what is the purpose/need for the tie under the rear of the tank. I have heard that leaving the tie out can cause the tank to split, why is that?

regards
kevin

 

[bmetcalf]

A cross-section looks like a tuning fork and when it vibrates, cracks occur. The tie bolt damps out the vibration enough to minimize cracking. It would be interesting for high mileage riders to report their tank experiences.

 

[Chris Launders]

What about a modern "plastic" sort of material, lots of bikes use them these days, I have a friend who is a rotory moulding specialist (where a hollow mould is rotated through all three axis to spread the "plastic" evenly over the inside to produce a hollow one piece container as in say a tank!!) I will have a word with him.
It could be made in black and I know he has done things with metal inserts (which would be needed for the filler,taps and possibly mounts)
Chris.

 

[davidd]

Panama,

I made a fuel tank for the Grey Flash in 1996. It was steel and I kept track of the hours which turned out to be 80. So, pick your hourly rate. Even assuming that I am incredibly slow, cut the hours in half. It is still expensive. The tank would have taken at least half the time in aluminum. This is the custom route.

If you were to do a production run with limited tooling, to pay for the tooling you would need 20 to sell units. If you offered the tank you specify in your first post, you might get one order, if you were lucky. Although twenty folks would be clamoring for the tank, what you would find is that some would decline because it was not the original material. Others would say they would buy one if it had more clearance around the carb. One would say he would by one if the hole for the oil tank "was just a little more generous." Another would want a little more capacity. The list of demands will exceed the original subscription.

This is not a complaint, just an observation. I think those who have supplied parts to Vincent owners know this dance quite well. It is just human nature. But even a small production tank would most likely cost $2500 in aluminum. Add shipping and painting and the knees start to go wobbly. Others will start to say, "I can get a Lyta tank for $400 and ......."

I would be very surprised if there is a plastic that will do the job. Manufacturers like Ducati and KTM have replaced huge numbers of tanks under warranty. I know that a friend with an old Buell plastic tank looked at his bike recently and all the paint had come off the tank. I think most plastic tank applications that are successful are hidden because they cannot live up to an acceptable cosmetic standard.

David

 

[Kansas Bad Man]

Panama,

I made a fuel tank for the Grey Flash in 1996. It was steel and I kept track of the hours which turned out to be 80. So, pick your hourly rate. Even assuming that I am incredibly slow, cut the hours in half. It is still expensive. The tank would have taken at least half the time in aluminum. This is the custom route.

If you were to do a production run with limited tooling, to pay for the tooling you would need 20 to sell units. If you offered the tank you specify in your first post, you might get one order, if you were lucky. Although twenty folks would be clamoring for the tank, what you would find is that some would decline because it was not the original material. Others would say they would buy one if it had more clearance around the carb. One would say he would by one if the hole for the oil tank "was just a little more generous." Another would want a little more capacity. The list of demands will exceed the original subscription.

This is not a complaint, just an observation. I think those who have supplied parts to Vincent owners know this dance quite well. It is just human nature. But even a small production tank would most likely cost $2500 in aluminum. Add shipping and painting and the knees start to go wobbly. Others will start to say, "I can get a Lyta tank for $400 and ......."

I would be very surprised if there is a plastic that will do the job. Manufacturers like Ducati and KTM have replaced huge numbers of tanks under warranty. I know that a friend with an old Buell plastic tank looked at his bike recently and all the paint had come off the tank. I think most plastic tank applications that are successful are hidden because they cannot live up to an acceptable cosmetic standard.

David

I made the tank for the SURTEES look alike racer , lotta work they BE !!! even from aluminum