ID of 3/8 oil supply hose on Commando

I have a variety of 3/8 hose bits from a variety of different suppliers, the id ranges from .310" to .350" when held in a round profile.
I'm making up a safe antisump valve and have some 1/2" barb SS barb fittings that are. 320" inside. If the stock hose is about this size then the barbs can be used as is. If the hose is much bigger than. 320, then the fittings will get bored out to match. The idea is to avoid adding any resistance to the supply line. The valve itself is 3/8" right thru.

I do not have a stock hose from a Norton here to measure without cutting into the line, not quite ready for that just yet.

Glen

The hose may well alter size with age so why not measure the bore of the solid feed/return pipe that bolts to engine crank case an if in doubt go for biggest bore you can get away with.

The stock 3/8th hose is around .350 ID.

But, the smallest restriction on the inlet side of the pump is around 1/4 inch in the cases so I don't think you have anything to worry about. Jim

Thanks, sounds like the fittings will work just fine as is.

Glen

I put a 3/8 valve in mine today so that the oil line can be turned off when not riding. Same Idea that you have. I have not fired it up yet but the ID of the valve I got was equal to the check valves sold by several parts houses.



Marc

Marc, do you have some failsafe method to insure that the valve is on before starting the engine?

Glen

worntorn said:

Marc, do you have some failsafe method to insure that the valve is on before starting the engine?

Glen

Click to expand...

Glen,

Not really and it does bother me somewhat. I did put a sticker on the speedometer to remind me. If nothing else if someone steals the bike they won't get far. :roll:

I will be thinking of a better fail safe reminder before I start riding the thing. Maybe make a key fob that has a big RED turn on the valve before riding on it or something.

Marc

Below is a table expressing the various hose id's you cited in terms of percent of a 0.350" hose cross sectional area. Keep in mind that friction loss in a line is also a function of length of restriction.

Dia. % area of .350 dia.

0.35 100%
0.32 84%
0.31 78%
0.25 51%

Say your feed line is maybe 10" long and the valve is maybe 1" long so not too much of an influence.

Should work just fine. As already noted above, human factor (forgetting) may be the most prominent. Maybe you could find a comparable valve with an electric indicator switch (valve open/circuit closed - valve closed/circuit open) and tie it into the ignition system. Someone, somewhere stated they used an electric solenoid valve but I don't trust electricity (can't see it).

I would also take it easy when the oil is bitter cold (really a cautionary statement in general) - but that's just me.

lomaxcm said:

worntorn said:

Marc, do you have some failsafe method to insure that the valve is on before starting the engine?

Glen

Click to expand...

Glen,

Not really and it does bother me somewhat. I did put a sticker on the speedometer to remind me. If nothing else if someone steals the bike they won't get far. :roll:

I will be thinking of a better fail safe reminder before I start riding the thing. Maybe make a key fob that has a big RED turn on the valve before riding on it or something.

Marc

Click to expand...

Develope a routine and stick to it. In some specific order, set a priority to the oil valve, like oil on, gas on, key on, tickle and kick.
It is true that it is not needed to turn the oil off all the time but I do because it is part of the habit.
Although many have incorporated an ignition interupt, I might think a simple idiot light would be less likely to strand you if your micro switch fails.

I used to have a valve on my old N15. I only shut it off if I was parking the bike in the garage and it was going to set for several days. Then I would remove the key from the switch and hang it on the valve.
Then when I would hop on the bike and I had to think about where the key was I would turn on the oil. It always worked for me. Jim

delete

pete.v said:

Although many have incorporated an ignition interupt, I might think a simple idiot light would be less likely to strand you if your micro switch fails.

Click to expand...

Could always clip/connect the two wires together in the event of a switch failure (fail to open); the wires would certainly be easily accessible to make this happen on the road side.

The other failure is if the switch "fails in the closed position" and you forget to open the oil valve since you had been relying on the valve switch - not good. Same weakness whether it is an ignition interrupt or an idiot light - a false signal could ruin your day.

Like the idea of a routine - pilots use check lists.

Without a failsafe method I am sure I would at some point forget. A friend who has a much better memory than I do finally fogot to turn the valve on after five years of use. He had a bit of a row with his wife and went out for a ride to cool off. As he was cooling the bike got very hot, as in things welded together internally.
I agree that a switch is a possible problem as well. Have toyed with a couple of switches here but did not like either the appearance or function of them or even the idea of trusting a switch to prevent catastrophic engine failure

So the plan is to make the ignition key into the operating lever for the valve. With the valve shut the key cannot be removed. With the valve open, the key comes out. Only use the one modified key and one hidden spare key. This is simple, that is what I do now. My second key is a regular key and has been taped to the frame in a hidden location for years. I would only use it in the event I am away from home and lose the modified key. In this situation the valve is left open anyway. Cant lose the key unless it is open plus the valve would only be shut when the bike is laid up for a week or more.


No wires, no extra switch to fail and hopefully a very small innocuous valve. And you cant start the bike without first turning on the oil supply.
I'll post some photos if it works out.

Glen

Dances with Shrapnel said:

pete.v said:

Although many have incorporated an ignition interupt, I might think a simple idiot light would be less likely to strand you if your micro switch fails.

Click to expand...

Could always clip/connect the two wires together in the event of a switch failure (fail to open); the wires would certainly be easily accessible to make this happen on the road side.

The other failure is if the switch "fails to close" and you forget to open the oil valve since you had been relying on the valve switch - not good. Same weakness whether it is an ignition interrupt or an idiot light - a false signal could ruin your day.

Like the idea of a routine - pilots use check lists.

Click to expand...

I have seen some pre-war bikes with the copper tubing running everywhere and a big-o-lever coming down from the oil tank feed line. It was special and with purpose.

These Nortons are not for everyone and not all can appreciate them and some down right take them for granted. But they are special and historic. We put thousands of dollars to make them reliable like a modern bike and that may be the misconseption for the are not and never will be a modern bike.

I feel these bike deserve a high level of respect and demand a certain level of responsibilty to own and operate.
I really love these bikes and I think I have enough know how to bring out the best to make it ride and feel as intended.

I get a little passionate. Here we have some poor guy who simply wants to know an appropriate ID for a feed line.

I think Glen has been around our block a few times, Pete. Anyhow, I kind of like his idea of the key/valve idea. I'm still not impressed with the fail safe switches, but mine has been working for me. I did run it without the switch for a while and I was constantly looking down at the lever. At my age I even forget if my zipper is up.

Dave
69S

DogT said:

At my age I even forget if my zipper is up.
Dave
69S

Click to expand...

People remind me all the time.

Now that I don't need the switches for the antisump valve, perhaps they could be used in a zipper down alarm

Glen

Don't get me wrong, Dave. I am in agreement with Glen. My point was that what ever we put on our bikes to do what ever we want them to do, that we be responsible to the bigger picture. These are just statements of how I feel about my Norton bike and Nortons in general. No arguement here.

I'm not disagreeing with anyone here, Pete. Just a good discussion, and Glen has put out a new wrinkle on the issue as far as I'm concerned.

Dave

"So the plan is to make the ignition key into the operating lever for the valve. With the valve shut the key cannot be removed. With the valve open, the key comes out."

That's the best idea I've heard yet.