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Oct 19, 2005
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Does the oil tank gravity head add to the oil pumps pressure or do the pump gears
just take what its feed and create their own pressure regardless of feed pressure?

Would 100 PSI oil fed into oil pump inlet push oil to crank and head to matter
for starting wear and ease?
What could be done for the cam lobes?
Would 40 PSI better as good or better?
Would seals blow out on 100 PSI?
About how long should pre pressure be applied to oil flush engine?

Is there something wrong with the oil system as it is?

Changing the pressure either from the feed or from the scavenge would adversely affect the dry sump action.
I sure hope nothing wrong with oil system once its up to speed.
I'll have pressure on tap and oil in frame-spine so just wondering on
something I don't know about yet, as fairly easy mod to do now.

This topic could turn into a can of worms....but here's my 2 bobs worth.

The head of pressure in the oil tank is insufficient to assist any pressure to the crank even if all obstructions were removed. You'd need a lot more oil a lot higher up, imagine a 44 gallon drum balanced on top of your helmet.

100PSI forced into the inlet line would backfire at the pump and blow the inlet line off. The pump has meshed gears, unless these rotate the forced pressure fluid would revert to the path of least resistance, most likely backward. It won't go forward to pressure the crank.

What could be done for the cam lobes - a seperate feed injection into the front of the cylinder barrel to flood the followers, or cross drill through the end of the camshaft timing side bushing, then through the middle of the shaft and cross drill the lobes at the base circle. A feedline would have to be fitted into the timing side crankcase to bring oil up to the cam bush. In other words, a whole new timing side crankcase. Or even better, fit a cam that is actually hardened to a reasonable standard, i.e not Norton OEM.

40 PSI is fine at 4,000 RPM at operating temperature. 60 PSI peak is fine too, but anything over that and you've got your own personal Gulf Of Mexico potential. That's why the pressure relief valve is there.

Don't understand what you mean about pre-pressure to flush engine oil. You can't pre-pressure a dry sump system. Get the motor and oil hot. Drain the sump, and the tank. Drink a beer. Relax. After about 10 minutes, when there is no more drip drip out of the tank and sump, put screw the plugs back in and refill with your favourite brand of oil. Add a new filter too if that's needed.

Messing about with "engine flush magic in a can" stuff is highly suspect for a Norton dry sump system. Use good quality oil high in ZDDP (see muliple threads of Biblical proportions on this) fit a new filter every 2nd change and do it around every 2,000 miles as a guide or at least once a year.

Too much pressure into the big end shells can, over time, wash off the white metal. You can put as much oil into an engine as you like as long as the scavenge is up to it.
If you put more pressure into the pump, I wouldn,t think you would get more out, the gears will create it's own feed.
Thanks for the gear head food ML and Swoshdave.
My project bike is 'Ms Peel'. Oil in frame with regulated
air hi and low pressure on tap, thought was for pre-starting oiling.

I'll take the 100 PSI back firing to heart and only think on a 40 PSI feed.
Hmm, if can't push much past static pump gears, will have
to review factory plumbing for a way around or drop idea.

Love the drilled cam idea, but would feed from the bulge
on DS case. Saving up for a MegaCycle cam as hard enough?

Drilled cam with feed from the DS bulge, could be done by diverting a line from the rocker feed (its under pressure) and tapping into the end, but remember the cam has some end float so a quill would be neccesary. Might be a solution to a non-existant problem is you get a decently made cam to begin with. Megacycle 560 series are a good product. Reface or fit new followers and use good quality oil and you'll get plenty of life out of it.

Racers have plumbed drilled cams from DS and head oil tap feed where some
breathers attach. I assume for softer cams and extra spring rpm endurance.
Cam is pulled to TS by tach drive gear IIRC. Don't know what a quill is??

Alas ML you may be right about wasted effort as posting plot thickens
and good MegaCycle cams at reasonable cost.

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