Topic: Irradicating the oil tank.

[few-regrets]

Since I don't see anyone else suggesting it (probably 'cause it's a dumb idea) ...what about using the frame as an oil tank? Would take some welding/inner radiusing but hey - if yer gonna dream - dream BIG! I remember the short lived Yankee 500 used the frame for oil ('least I THINK I remember that) and some Brit bikes too. Use an oil cooler in the front to bridge the "in" side to the "out" side and don't rest yer leg on the hot side of the frame no mo! That would be soooo cool!

Lemme know how it works out (if it works). And if it doesn't I'll claim that someone stole my identity.

[scottly]

Mick, you need an oil tank, period. There are only cons for trying to convert a properly designed dry-sump system to wet-sump.

[754]

Consider this;
 Remove stock pan, mill up a piece that bolts to the original mounts but extends rearwards at least 6 inches x the pan width.  Approx 1 inch thick. This piece will be open on the bottom and should be firmly mounted to a case bolt or 2, using a spacer at the rear to support the weight. Now mill out a lower half that will bolt to this, it will be finned and hold all the engine oil. This works well on the Dyna glides.
 The trick is to keep oil level near where it normally sits, and it should work fine, return line, may have to feed back into this sump.
 Now the next problem, it may need a trap-door like a Kawi, to prevent the oil flowing to the back under extremely hard acceleration.

 My thought of late is to build an alloy tank in the lower part of the triangle. It probably will only have to be 5 -6 inches wide at the tip, and will still open up 80% of the triangle..

[scottly]

 My thought of late is to build an alloy tank in the lower part of the triangle. It probably will only have to be 5 -6 inches wide at the tip, and will still open up 80% of the triangle..

I have also been thinking about an alloy tank, but similar in configuration to the stock tank, incorporating a similar oil separator in the breather.
I wonder how much lighter an alloy tank would be than the stock unit? 

[754]

 1/2 to a1/3 the weight.
 What is the wet weight now??, need to get you under 400...

[scottly]

Getting mighty tempted to mock it all up with one un-drilled disc and putting it on the scale...

[754]

I got some measurements, need someone to calculate volume, for me.. no calculater here.

 First is a triangle that is 7.5 across base x 5.5 high x 9 inches long.
 2nd is  triangle  9 in across base  x 7 in high x 9 long.

 A Cdn qt is  3.94 dia by 6.5 long for reference..

 Ehen we can see if it holds enough oil.

[Frankencake]

1st  20.58 sq in.



2nd
29.02 sq in.

http://www.analyzemath.com/Geometry_calculators/herons_area_triangle.html

[754]

that is area, not volume.
 to try to explain better;

 Triangular tank fits in bottom of frame triangle. frame is 9in between rails. tank is viewd from end, making 2 triangles, first is 7.5 x 5.5, nd is 7 x 8.. both of those will be x 9in long

[754]

1.87 squared x pi x 6.5 = cu inches in a cdn qt of oil.

 71.4 cu inches= qt

 20.6 x 9= 185.6 cu inches... about 2.6 qts..

 
7x 9 x9 = 283.5 cu in.......4 qts..

 the bigger triangle, leaves the top 5 inches of frame trianle open.. the smaller would leave 6.5 inches open.
 I think small size will work as I did not count going past frame toward tire= even more room..

[Retro Rocket]

Consider this;
 Remove stock pan, mill up a piece that bolts to the original mounts but extends rearwards at least 6 inches x the pan width.  Approx 1 inch thick. This piece will be open on the bottom and should be firmly mounted to a case bolt or 2, using a spacer at the rear to support the weight. Now mill out a lower half that will bolt to this, it will be finned and hold all the engine oil. This works well on the Dyna glides.
 The trick is to keep oil level near where it normally sits, and it should work fine, return line, may have to feed back into this sump.
 Now the next problem, it may need a trap-door like a Kawi, to prevent the oil flowing to the back under extremely hard acceleration.

 My thought of late is to build an alloy tank in the lower part of the triangle. It probably will only have to be 5 -6 inches wide at the tip, and will still open up 80% of the triangle..

Thanks Frank, i have already had someone offer to make me a billet sump with more volume and i still can't see why this couldn't be done. The sump would have to be baffled to stop both surge and starvation. I would like to know what Harley did different on the models that they run a sump on....Keep the banter going guys, its all interesting...Oh,do the 750 auto's have an oil tank?

Mick

[Alan F.]

...Oh,do the 750 auto's have an oil tank?

Nope, none at all.

[IHWillys]

I'm just throwing this out there for further thought/discussion/striking down.  I'm no expert. 

In a dry sump system the scavenge pump typically pumps at a different volume rate than the pressure pump.  I don't know if this is the case with the 750. 

So if wet sumping a dry sump system I think one could basically feed the scavenge pump outlet to the pressure pump inlet but would require a relief valve between them, with the relief feeding back to the sump. 

Ken

[scottly]

The whole idea of a dry sump is to keep as much oil as possible away from the "windage" from the crank, which at high RPM can pull the oil out of the sump and wrap it around the crank, robbing horsepower. The tank itself is a reservoir, whose level may rise and fall with RPM, while still ensuring a supply of oil to the pressure pump.   

[754]

What I meant by the extended rearward oversize sump was,

 Keep the oil level the same as in the stock pan (can be determined by draining the pan) then run correct amount of oil at that level.. thinking return line can be looped back into sump, maybe  passing thru cooler on the way..

 Raising the oil level above stock would probably cause windage problems..

[scottly]

What is the advantage? At best lower center of gravity with the bulk of the oil carried under the crank, instead of up in the tank. I wish I knew how much a stock, early-style tank weighed.

[754]

 The whole point is to clean up the triangle.. make the bike look leaner, and  a look rarely ever seen..

[scottly]

Oops. Sorry, I tend to worry about weight, and where it's at, more than looks. Come to think of it, though, a clean triangle would really make the Webers stand out! If I do build an alloy tank from scratch, I will keep this aspect in mind...

[lordmember1969]

...Oh,do the 750 auto's have an oil tank?

Nope, none at all.

Is it the same oilpump on the 750A as the rest?

[Retro Rocket]

What is the advantage? At best lower center of gravity with the bulk of the oil carried under the crank, instead of up in the tank. I wish I knew how much a stock, early-style tank weighed.

Lower weight or lowering the centre of gravity a little had occurred to me. A baffled sump would prevent the crank picking up excess oil as long as the correct amount of oil was used. Another reason to do it is that because i can....   And i have never seen it done.

As lordmember asked, is the rest of the oil system in the auto the same..?

Mick

[754]

 I think back in the 80s Billy Budde had 750s with out the oil tank.. and the coolest, and I do mean THE..coolest custom pipes you could have imagined..

[Retro Rocket]

I think back in the 80s Billy Budde had 750s with out the oil tank.. and the coolest, and I do mean THE..coolest custom pipes you could have imagined..

Got any pics Frank.? I would love to see that...

Mick

[754]

Try a search for Billy Budde Customs in San Leandro..
 His stuff was often in Street Chopper, later he did some H-D stuff.
 Pretty clever fellow, he ran  stuff like cams in 750 to fire  both pistons at once, and he built and offered fuel injection for H-Ds back in the 80s or early 90s.
 His shop was very near Arlen Ness, when I went there once I thin I tried to find Billy.. I think the shop was closed.. or something..

[Syscrush]

Try a search for Billy Budde Customs in San Leandro..

Is this it? (click for larger)

[Syscrush]

I'm interested in this - I hate the look of that oil tank.

It would not be hard (and maybe not that expensive) to have a nice sheetmetal oil pan made up so you could have whatever shape and volume you want.  Just don't know enough about hydraulics in general and oiling systems in particular to know how much that buys you.