Wet sumping - better to leave it?

Status
Not open for further replies.
I also have the NYC reed valve breather kit (designed by Jim Comstock, now produces by NYC Norton) on my recently rebuilt Commando. Besides aiding the wet sump issue, there is never a drop of oil under the bike and the bottom of the engine is totally oil free. The bike also seems to accelerate more quickly with the reduced case pressures, or so it seems. I believe it to be an excellent modification. Jim and Kenny know their stuff..
 
I am an idiot. My bike sits with a bolt stuffed up its oil feed pipe until I am ready to race. Then I reconnect the pipe and start the motor. I have still forgotten to tighten the clip on the return pipe and ended up with oil pissing onto the ground. I have thought about using a cock with a switch to disconnect the ignition. But everything I think of would introduce another opportunity for failure.
 
I am an idiot. My bike sits with a bolt stuffed up its oil feed pipe until I am ready to race. Then I reconnect the pipe and start the motor. I have still forgotten to tighten the clip on the return pipe and ended up with oil pissing onto the ground. I have thought about using a cock with a switch to disconnect the ignition. But everything I think of would introduce another opportunity for failure.

How often do you actually race?
 
Probably as often as I do when the morning coffee starts flushing my kidneys and I race from the back shed to the bathroom, or a nearby tree with ample cover..... Heh heh.
 
I have a reed valve on the 750 left side case mount and I see some oil run through it on start up after non use for a week or so. So I guess some oil gets splashed up to and pushed through the hollow cam etc. But I've never had a main seal blow out ever - even before the reed valve.

I'm sure locating it low in the case would move more oil.

Wet sumping - better to leave it?
 
Just ride the bloody thing and not worry about it, if I do let my Norton sit for some time (as I have 2 other bikes) I check the oil level the night before and if its down I just pull the drain plug and refill the tank next day before I go out on the bike, 30 seconds to unscrew the drain plug and another 30 seconds to put it in and a minute to refill the oil tank, but I only need to do that if it sit for over 6 months, to me no big deal, mine has only wet sumped 2 times in 46 years of owning it, if I let its sit there is other maintenance to do while you drain the oil out of the sump before riding it anyway.

Ashley
 
Well then I'm an idiot too! After my motor blew up I ditched the one way valve, had AMR re-do the timing cover and install seals in the oil pump. My Norton is wet sump free. It can sit unused for two months and there is minimal loss of oil level in the tank.
Ride On
Dave
I had AMR do their ball type valve mod and oil pump mod as well. It will still wet sump but at a MUCH lower rate. Happy customer! :)

Regards,
~998cc
 
Just ride the bloody thing and not worry about it, if I do let my Norton sit for some time (as I have 2 other bikes) I check the oil level the night before and if its down I just pull the drain plug and refill the tank next day before I go out on the bike, 30 seconds to unscrew the drain plug and another 30 seconds to put it in and a minute to refill the oil tank, but I only need to do that if it sit for over 6 months, to me no big deal, mine has only wet sumped 2 times in 46 years of owning it, if I let its sit there is other maintenance to do while you drain the oil out of the sump before riding it anyway.

Ashley

It takes you longer than 30 seconds to find the wrench, find the pan, and then crawl under the bike. So I doubt you’re riding in a minute. I’m sure a video will prove me wrong.
 
I have a reed valve on the 750 left side case mount and I see some oil run through it on start up after non use for a week or so. So I guess some oil gets splashed up to and pushed through the hollow cam etc. But I've never had a main seal blow out ever - even before the reed valve.

I'm sure locating it low in the case would move more oil.

Wet sumping - better to leave it?
Jim,
You also do one for the combat type. what tests have you done with that unit.
Or who has one that can report?
T
 
Still have not heard a good reason not to fit a manual valve with an ignition defeat switch. Cost for mine was maybe $15 in hardware store parts and a micro switch. Cannot start up unless valve is fully open. No sumping at all.
 
It takes you longer than 30 seconds to find the wrench, find the pan, and then crawl under the bike. So I doubt you’re riding in a minute. I’m sure a video will prove me wrong.

Like most owners of old Brit twins, I've gone thru this procedure many, many times.
It still takes me quite awhile, maybe I'm getting slower. Its
more like half an hour once the mess is cleaned up, things are put away and I'm riding.
I didn't time the last go, it might have been more than half an hour as I recently realized that the drained oil usually has some road grit in it. The upside down done by feel cleaning of the area around the drain doesn't completely clean things. The oil needs to be put through a strainer before it's going back in the bike.

After blowing a seal on the MK3 some years ago, I don't care for the full sump start.
Then there's the smoke and all that crap burning onto the combustion chamber and valves.



Sometimes I just ride the bike with the valve instead. That one is ready to go in seconds.



Glen
 
Last edited:
Still have not heard a good reason not to fit a manual valve with an ignition defeat switch. Cost for mine was maybe $15 in hardware store parts and a micro switch. Cannot start up unless valve is fully open. No sumping at all.

The best reason to avoid a contraption like that is the micro switch can fail. As long as you trust the switch you’ll be fine. How good of quality is your switch?
 
Jim,
You also do one for the combat type. what tests have you done with that unit.
Or who has one that can report?
T
Its a given that the combat type pumps out more oil after wet sumping simply because its located low in the sump. With a clear braided hose you can view the oil being pumped out and then clearing. You can make this conversion to any Commando but it requires drilling 3 holes as shown below (Maney case example). Milling is not necessary because a fiberglass reinforced silicone gasket is provided to prevent leaks.

Wet sumping - better to leave it?


Wet sumping - better to leave it?
 
The best reason to avoid a contraption like that is the micro switch can fail. As long as you trust the switch you’ll be fine. How good of quality is your switch?

I bought one of those contraptions off of flea bay. It was a cheap piece of crap. I threw it away and bought a proper one from Feked. I test it by
turning the oil supply off. Voila, the engine shuts off.
Speaking of dubious engineering, how good of quality is your oil pump seal?
 
I bought one of those contraptions off of flea bay. It was a cheap piece of crap. I threw it away and bought a proper one from Feked. I test it by
turning the oil supply off. Voila, the engine shuts off.
Speaking of dubious engineering, how good of quality is your oil pump seal?

Nothing wrong with my oil seal. Helps to have a gauge or warning light too.
 
The best reason to avoid a contraption like that is the micro switch can fail. As long as you trust the switch you’ll be fine. How good of quality is your switch?
True. But consequence of switch failure would be no start as it is a N.O. type, unlikely to fail in a closed condition. Easy to bypass it if out on the road and it fails.
 
Jim, can the Combat type in your pictures be installed on a 1968 commando? Thanks.
 
Status
Not open for further replies.
Back
Top