Oil in frame

jseng1

jseng1

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Here's an interesting frame photo I lifted off the classic racer forum. Would like to see this with Commando style steeper tilted shocks.

Oil in frame
 
Mart UK said:
Be interesting setting the float heights for that carb angle.
Click to expand...
The fork has no springs in it, so it's not quite as bad as it might look at first glance.

I'm interested in how the double down tubes connect to the bottom of the spine, and how the swingarm interacts with all of it. There's a lot going on right there.
 
lcrken said:
Can you post a link to that forum? Thanks.

Ken
Click to expand...
It was posted 2-22-24 it Facebook "classic motorcycle racing" search under "newest activity" The link doesn't work when I paste it here.
 
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How much oil would it hold in the frame, with a high revving race bike the more oil the tank holds better for cooling, I know the oil in frame Triumph didn't hold too much oil in the frame 2/3 ltr at the most and the oil was always hot till I installed a Lochead oil cooler, but then I run oil coolers on all my old British bikes for our hot climate and oil in a thick wall frame cube the oil will take longer to cool down, also need that air space above the oil and the filler cap, so is an oil in the frame such a good idea for a race bike, a light weight alloy oil tank be so much better for cooling in my opinion.

Ashley
 
ashman said:
How much oil would it hold in the frame, with a high revving race bike the more oil the tank holds better for cooling, I know the oil in frame Triumph didn't hold too much oil in the frame 2/3 ltr at the most and the oil was always hot till I installed a Lochead oil cooler, but then I run oil coolers on all my old British bikes for our hot climate and oil in a thick wall frame cube the oil will take longer to cool down, also need that air space above the oil and the filler cap, so is an oil in the frame such a good idea for a race bike, a light weight alloy oil tank be so much better for cooling in my opinion.

Ashley
Click to expand...
With an OIF Triumph, the filler cap is at the top of the vertical leg of the frame, just in front of the seat.

This frame has the filler cap right behind the head stock (where it should be) so it will have more than double the oil capacity of an OIF Triumph.
 
But with any oil tank you still need that air space weather in a tank or frame.
 
ashman said:
But with any oil tank you still need that air space weather in a tank or frame.
Click to expand...
Agreed, you can’t fill that OIF to the brim !

The effect of hard braking will also be a consideration.

The ideal fill height could only be arrived at via trial and error I guess.
 
There are advantages to oif
The main one IMO is the whole frame acts as an oil cooler
It takes up less space
You don't have the additional weight of an oil tank
The only disadvantage I can think of is they are difficult to clean out
 
baz said:
There are advantages to oif
The main one IMO is the whole frame acts as an oil cooler
It takes up less space
You don't have the additional weight of an oil tank
The only disadvantage I can think of is they are difficult to clean out
Click to expand...
Even that’s not an issue if the spine has a big sump plate like an OIF Triumph.

Take off the sump plate and filler cap and it couldn’t be an easier thing to clean out IMO.
 
Fast Eddie said:
Even that’s not an issue if the spine has a big sump plate like an OIF Triumph.

Take off the sump plate and filler cap and it couldn’t be an easier thing to clean out IMO.
Click to expand...
Yep I agree
But have you tried cleaning out a b25/b50 type frame?
They are very difficult to clean
Some say the remainder of the last 3 engine blow ups are retained in the rear section 🤣🤣🤣🤣
 
The tube on that Norton frame looks to be about 3" dia. which is the same as a Triumph/BSA P39 type. As standard they hold 4 pints, but when modified to top fill hold 7 pints with room to spare. I have just finished converting another one to do that, & also to take a T160 motor. Over the past twenty years I've changed five of them, twins & triples, & they run much cooler with zero problems. I also leave the original filler in place to aid cleaning when necessary.
 
Matchless said:
The tube on that Norton frame looks to be about 3" dia. which is the same as a Triumph/BSA P39 type. As standard they hold 4 pints, but when modified to top fill hold 7 pints with room to spare. I have just finished converting another one to do that, & also to take a T160 motor. Over the past twenty years I've changed five of them, twins & triples, & they run much cooler with zero problems. I also leave the original filler in place to aid cleaning when necessary.
Click to expand...
Did you mention in the past that you remove the oil cooler when fitting a triple into an oif ?
 
Matchless said:
I have just finished converting another one to do that, & also to take a T160 motor. Over the past twenty years I've changed five of them, twins & triples, & they run much cooler with zero problems. I also leave the original filler in place to aid cleaning when necessary.
Click to expand...
A Commando frame using an OIF design is an intriguing project.
Martyn: Do you have pictures of your P38 mods? Did you change the failure prone boss for the swinging arm as well?

- Knut
 
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I would love to see more information on modifications like these. My friends old 750 short stroke race bike was converted to OIF. He had some other cool modifications on it. I couldn't afford to buy it at the time, but really wish that I had taken some reference pictures before it was sold off as part of his estate.

RSR
 
My Antig
Needs some mods when it next gets built. I want to fit a reed valve lol. I had lots of leaks, filler cap at the top & drain bolt at the bottom. Was oily around the swinging arm spindle area but was never sure if that was the frame. 3 1/2 ltrs! Not my idea of safe but such short classic races now.
Oil in frame
 
baz said:
Did you mention in the past that you remove the oil cooler when fitting a triple into an oif ?
Click to expand...
Yes the oil cooler & thermostat was removed from my 930 O.I.F. T160, after talking to Richard & Dave when I was at P&M. They mentioned a customer of theirs in Spain, who found it simply wasn't necessary.
 
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mdt-son said:
A Commando frame using an OIF design is an intriguing project.
Martyn: Do you have pictures of your P38 mods? Did you change the failure prone boss for the swinging arm as well?

- Knut
Click to expand...
I do have some pictures of the mods but can't retrieve them just yet. They are in my old lap top which has crashed, something called the Blue wall of death I believe. I'll be taking it to a mate of mine in a few weeks to see if he can rescue my files, as I haven't got a clue how to.
Failing that I'll be doing another frame for a T160 in the very near future, so will post piccies then.
Also, I do brace the swing arm pivot tube with a 3mm x 20mm strap which I bronze weld around the main tube & back to the s/a tube.
 
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