Fiberglass oil tank

t ingermanson

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In the interest of heading off the inevitable parade of fatigue failures with my aluminum tank, I've decided to replace my Manx-style central oil tank with a fiberglass one. Anyone know who makes one? Unity seems to have dropped off the map. For a wideline. No need for a battery box.

Thanks
 
If you have a petrol fire with a motorcycle, it is nasty. But when the oil also catches fire, it becomes almost impossible to extinguish. I would not use plastic oil lines on a road bike. It has only ever happened to me once, and that was enough. I was lucky - a car driver stopped and helped me. Without him, I would have lost the bike.
 
Why not mount a round alloy oil tank on your Wideline I been using one on my Wideline for about 15 years now without any problems and is very light, the top of the tank is mounted under my tool tray under the seat and bottom mount to the top cross section for the top rear engine mount all rubber mounted of course, I brought my round alloy tank from Lowbrows, it fits great and looks good.
Fiberglass oil tank
 
Why not mount a round alloy oil tank on your Wideline I been using one on my Wideline for about 15 years now without any problems and is very light, the top of the tank is mounted under my tool tray under the seat and bottom mount to the top cross section for the top rear engine mount all rubber mounted of course, I brought my round alloy tank from Lowbrows, it fits great and looks good.
Nah. No thanks. I know what I want.
If you have a petrol fire with a motorcycle, it is nasty. But when the oil also catches fire, it becomes almost impossible to extinguish. I would not use plastic oil lines on a road bike. It has only ever happened to me once, and that was enough. I was lucky - a car driver stopped and helped me. Without him, I would have lost the bike.
While there's a remote chance of an oil fire, I'm much more concerned about the likelihood of oil on my tire.
 
All good I was just throwing it in there, I have a central alloy oil tank for my Slimline frame.
 
Dave Degans used to insist on fiberglass oil tanks I believe I read
Because of vibration cracking alloy tanks on his Tritons
 
Dave Degans used to insist on fiberglass oil tanks I believe I read
Because of vibration cracking alloy tanks on his Tritons
That's what I'd heard too. Upon a more extensive Google image search of Dresda Tritons, it appears to be the case, But I don't really care for that stepped style along the front face. It might buy a teeny bit more capacity, but I don't seem to have trouble with that with my current (smaller, late Manx-style) one.

Perhaps I'll build my own. Always looking to make my life as difficult as possible. Seems the Norton oil filter banjo bolt has a 1" x 20 tpi thread, but does anyone know the thread form? UNC? I'd guess the Norton part thread predates the Unified standard if it goes back to the prewar bikes? BSP? UNS?

Can of worms open...
 
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That's what I'd heard too. Upon a more extensive Google image search of Dresda Tritons, it appears to be the case, But I don't really care for that stepped style along the front face. It might buy a teeny bit more capacity, but I don't seem to have trouble with that with my current (smaller, late Manx-style) one.

Perhaps I'll build my own. Always looking to make my life as difficult as possible. Seems the Norton oil filter banjo bolt has a 1" x 20 tpi thread, but does anyone know the thread form? UNC? I'd guess the Norton part thread predates the Unified standard if it goes back to the prewar bikes? BSP? UNS?

Can of worms open...
That’s an awful lot of work just to avoid a step that you’d hardly even notice when fitted!

You‘re quite right, the shape is intended to maximise capacity whilst allowing room for carbs etc.
 
The aluminium oil tank on my Seeley has a tube welded across the top of it at the back. It has rubber in it, and the front af the tank sits on a rubber pad, on the engine plates. Guys who have not raced much often do not understand the importance of rubber-mounting as much as possible to stop cracking. On a Commando, it is not so bad - the isolastics stop a lot. But I would not use isolastics on a race bike. That connection between your brain,, the handle bars and the rear tyre contact patch is what stops you from crashing. - 'There is a fine line between pleasure and pain' ?

There is a thing which puzzles me about Colin Seeley. For a sidecar guy, he knew a lot about solos. - His frames are magic.
I raced a featherbed Triton for yonks, and I have ridden others as well as a Manx. The Mk3 Seeley is better.
I have not ridden a 1963 Triumph Bonneville, but I can remember them giving the Manxes a run for their money.
The advantage of a Manx is in it's oversteer as you accelerate - it inspires confidence. The Seeley does much more of that.
The problem is, if you ride the Seeley normally, you never suspect what it can really do. With a Manx you find out almost immediately. As soon as you accelerate outb of a corner, you can feel a Manx helping you. With the Seeley, it self-steers a lot in the correct direction,as soon as you gas it when on a lean, often when you have just entered a corner.
 
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That’s an awful lot of work just to avoid a step that you’d hardly even notice when fitted!

You‘re quite right, the shape is intended to maximise capacity whilst allowing room for carbs etc.
Yea. I agree. It is a lot of work, but so is the amount of work rebuilding all the infrastructure to hold the tank, remounting the oil filter hidden underneath, etc, etc. The tank in question has some pretty unique mounting (isolastic-style dampers) to which I adapted the frame, so it's a hornet's nest of problems to dig into. My carbs clear, my cables clear, my hoses clear, my electrical clears, so that's the size and shape I'm going with!

I also want to build an Elephant Foot tank, make a mold for an early 50s manx seat, and a primary belt cover is mostly done, so it's just another thing to do really. Fiberglass is pretty fun and suits my brain's idiosyncrasies, and building things is a compulsion I've yet been able to get under control. What do ya do?

The aluminium oil tank on my Seeley has a tube welded across the top of it at the back. It has rubber in it, and the front af the tank sits on a rubber pad, on the engine plates. Guys who have not raced much often do not understand the importance of rubber-mounting as much as possible to stop cracking.
The tank is 100% rubber mounted and doesn't touch a single item that is not rubber, nor is it held down tightly. It has failed in the past and will continue to fail with the fatigue of being surrounded by a heavily vibrating motorcycle while filled with thick vibration damping oil. All its fractures have been along the bottom seam, not where it mounts at the top. The welding repairs just exacerbates the weakening of the aluminum. I've got around 7000 miles on the tank (much more than your average race bike after as many years), so I think it's time to go. I have not raced though, so what do I know?

I was looking for a carbon fibre version of a Molnar Manx central oil tank for ages couldn't find one.. If you do find someone willing to make them post here please!
I thought of making my own but after a seat pan/hump I realised I have little interest in mucking about with fibre glass/carbon fibre production.
I'll be making some parts for myself, but the oil tanks will be pretty time consumptive, so pretty expensive if I choose to make and sell any more. It will need to be a three part mold, leading to a clamshell to be bonded shut, all with custom made bungs for the plumbing and mounting. Anything I make will be fiberglass and not carbon fiber. Carbon fiber is horrendously abrasive, and not so good for breathing. I've done projects with it in the past, and I'm definitely over it. It's a lung and tool killer.


The oil filter bolt is 1"-20 UNEF, by the way. The tap on its way, and the plug is mostly done. Too late to turn back now...

Should I post progress?
 
Yea. I agree. It is a lot of work, but so is the amount of work rebuilding all the infrastructure to hold the tank, remounting the oil filter hidden underneath, etc, etc. The tank in question has some pretty unique mounting (isolastic-style dampers) to which I adapted the frame, so it's a hornet's nest of problems to dig into. My carbs clear, my cables clear, my hoses clear, my electrical clears, so that's the size and shape I'm going with!

I also want to build an Elephant Foot tank, make a mold for an early 50s manx seat, and a primary belt cover is mostly done, so it's just another thing to do really. Fiberglass is pretty fun and suits my brain's idiosyncrasies, and building things is a compulsion I've yet been able to get under control. What do ya do?


The tank is 100% rubber mounted and doesn't touch a single item that is not rubber, nor is it held down tightly. It has failed in the past and will continue to fail with the fatigue of being surrounded by a heavily vibrating motorcycle while filled with thick vibration damping oil. All its fractures have been along the bottom seam, not where it mounts at the top. The welding repairs just exacerbates the weakening of the aluminum. I've got around 7000 miles on the tank (much more than your average race bike after as many years), so I think it's time to go. I have not raced though, so what do I know?


I'll be making some parts for myself, but the oil tanks will be pretty time consumptive, so pretty expensive if I choose to make and sell any more. It will need to be a three part mold, leading to a clamshell to be bonded shut, all with custom made bungs for the plumbing and mounting. Anything I make will be fiberglass and not carbon fiber. Carbon fiber is horrendously abrasive, and not so good for breathing. I've done projects with it in the past, and I'm definitely over it. It's a lung and tool killer.


The oil filter bolt is 1"-20 UNEF, by the way. The tap on its way, and the plug is mostly done. Too late to turn back now...

Should I post progress?
Absolutely....have you thought about using Kevlar ?

 
Absolutely....have you thought about using Kevlar ?

Always think about it all too much... Kevlar (or any woven cloth) weave isn't great for complex shapes. The tank isn't that complex, but there's a lot of pretty tight corners for how much flat there is. It'll be mostly a medium weight chopped strand fiberglass mat, with a few patches of woven cloth for where I'll have to drill it and glue in the bungs. Maybe some woven cloth on where the two halves meet to have nice strong edges. The mat lays down in all the corners really nicely, and is plenty strong for this application. I think...
 
Always think about it all too much... Kevlar (or any woven cloth) weave isn't great for complex shapes. The tank isn't that complex, but there's a lot of pretty tight corners for how much flat there is. It'll be mostly a medium weight chopped strand fiberglass mat, with a few patches of woven cloth for where I'll have to drill it and glue in the bungs. Maybe some woven cloth on where the two halves meet to have nice strong edges. The mat lays down in all the corners really nicely, and is plenty strong for this application. I think...
Its bloody strong and malleable...just a thought....
Example only👇
 

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