Oil in frame commando

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Joe Schlaberdowski

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In about 1971 when I still had my 1966 Matchless Norton, I was sure the frame had been bent slightly, as if a previous owner ha run into a parked car or wall at a fairly low speed. But still enough to put a slight wrinkle where the down tube joins the steering tube and just above that two inch long"pipe" welded crossways to the down tube. I think that pipe is to attach a side car, but not sure. Anyway it looked a little wrinkled there so I went to a welder in Indianapolis who was said to work on bike frames. He had about 6 or 7 Norton frames sitting about, 4 featherbeds and 3 Commandos. He showed me several rather new Commando frames he was modifying to hold the oil in the large top tube. The large top tubes had small tubes welded into them for the oil feed. They came out the top and curved over to follow closely the lin of the top tube to fit under the gas tank, being about 8 inches in length. It looked pretty neet, but I was never sure how much use it was besides looking "neet". Anyone ever hear of this? By the way I've used the terminology for bicycling frames, but perhaps the terminology for motorcycle frames is a bit different. Sorry for any confusion.
 
Bernhard said:
Google "oil on frame Norton" and several come up on internet.
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And at least several from access Norton. Didn't know. I think I would like it modular like the standard tank. Something goes wrong (but don't know what really) and there goes the frame. Someboy back then must have thought it was advantageous.
 
Joe Schlaberdowski said:
In about 1971 when I still had my 1966 Matchless Norton, I was sure the frame had been bent slightly, as if a previous owner ha run into a parked car or wall at a fairly low speed. But still enough to put a slight wrinkle where the down tube joins the steering tube and just above that two inch long"pipe" welded crossways to the down tube. I think that pipe is to attach a side car, but not sure. Anyway it looked a little wrinkled there so I went to a welder in Indianapolis who was said to work on bike frames. He had about 6 or 7 Norton frames sitting about, 4 featherbeds and 3 Commandos. He showed me several rather new Commando frames he was modifying to hold the oil in the large top tube. The large top tubes had small tubes welded into them for the oil feed. They came out the top and curved over to follow closely the lin of the top tube to fit under the gas tank, being about 8 inches in length. It looked pretty neet, but I was never sure how much use it was besides looking "neet". Anyone ever hear of this? By the way I've used the terminology for bicycling frames, but perhaps the terminology for motorcycle frames is a bit different. Sorry for any confusion.
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Here's a custom O.I.F. Commando:

 
I am impressed. Still, anyone know the advantage of it -- besides the inside of the frame tube never rusts. Does it act a bit like an oil cooler?
 
Just looked at the video. The bike's really well done though the video bounces around a bit too much. Was trying to see clearly the oil-in-frame fittings. But a beautiful bike I must say.
 
Joe Schlaberdowski said:
I am impressed. Still, anyone know the advantage of it -- besides the inside of the frame tube never rusts. Does it act a bit like an oil cooler?
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Not any more of an oil cooler than a typical oil tank. The volume of the O.I.F. vs the volume of the oil tank would be the relevant factor ..... that is, if the oil recirculation time is longer (more volume), then the oil has longer time to cool before going around again.

Hobot on this Forum had O.I.F. You might search on oil in frame under his authorship for more info.

Slick
 
A buddy of mine had an absolutely beautiful Trumpet Tiger 650 which had the oil in the frame. All I really recall is the motor burning up 3 times because of lubrication issues. The frame reservoir probably was unrelated, but just the association of it ruins the method in my mind. The motor was rebuilt by a Trumpet builder of note in the Austin area each time also so I would guess it was never meant to be.... Joe's bedtime story is over tonight.

I wanted to buy that bike so bad too.
 
I have seen videos of modern air cooled bonnevilles modified to OIF by plumbing the two down tubes. This to do away with the external oil to air radiator.
 
Joe Schlaberdowski said:
I am impressed. Still, anyone know the advantage of it -- besides the inside of the frame tube never rusts. Does it act a bit like an oil cooler?
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Space is at a premium on most two wheels bikes. It's a hard enough job trying to cram everything in the frame. If you are smart you can use/ get one component to do two jobs at the same time..
 
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That would be so cool that is until you get an oil leak that puts it all over your back tyre.
 
I weld repaired two OIF Triumphs, the swing arm pivot to main spine was cracked. Both bikes had high miles, one was 75,000. Like Bernhard’s post, the rear wheel was getting misted.
 
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What are the pros and cons?

As I see it,

Pros

1) make use of dead space, thereby
2) gaining space to use for other things (per Bernhard)
3) saving weight by eliminating the oil tank.
4) using the oil tank for extra fuel for long hauls. Maybe make the oil tank the fuel reserve.
5) cooler oil if the forward facing down tubes can be part of the O.I.F.
6) cooler oil if the frame volume is greater than oil tank volume, and you use that volume for more oil, thereby increasing the residence time of oil before it recirculates.
7) increased resale if the prospective buyer thinks the mod is positve.

Cons

1) higher center of gravity (but this is likely insignificant)
2) greater head pressure on the oil pump, leading to increased rate of wet sumping. This assumes the central spine, not swingarm is the reservoir.
3) depending on how clever one is, the oil filler cap, and drain plug may be a bother to get to.
4) hotter oil temperature if the frame volume is less than 2 liters.
5) decreased resale value if the prospective buyer thinks originality is positive.

It boils down to individual preferences.

Slick

Edit:

Another Pro

Eliminate the problematic oil tank mount if the tank is removed.

Another Con

Per worntorn below ..... possible slag in the oil reservoir. One would need a serviceable screen to catch it. One thing leads to another .... per MichaelB below.
 
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Kenny Dreer did it on his VR 880's. He had a cooler in the oil bag location to augment capacity.
Filler cap was at the top of the tube at the neck, which meant modification to the fuel tank.
One thing leads to another. Not sure it gains anything other than eliminating the leaky oil bag.
It's a lot of work..
 
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