Atlas Rocker Spindles

marshg246 said:

In the high pressure system (rocker oil fee to the sides of the head):

If not facing away from center too much oil will be in the head all the time and especially the intake side will be flooded with oil.

I appreciate and agree with your thinking but since the drainage is poor, especially in the intake side, over oiling is a problem. By the same token, the holes through the head that deliver oil to the slots in the end of the spindles do not line up well - "fix" that and you'll also be over oiling.

Click to expand...

So my Atlas feeds from the top of the head, has a 6 start pump, and originates from the crankcase... so it also is high pressure as I understand it and as Slick has said the plain ( no flats ) spindles that I have should all have the oil hole facing the valves. Correct?

jms said:

So my Atlas feeds from the top of the head, has a 6 start pump, and originates from the crankcase... so it also is high pressure as I understand it and as Slick has said the plain ( no flats ) spindles that I have should all have the oil hole facing the valves. Correct?

Click to expand...

I should have stayed out of it. I know almost nothing about pre-Commando. I was just trying explain why the feed was away from the hole in the rocker.

L.A.B provided much more info about the "flats". The flats I'm talking about have the oil hole in them and the spindles are not scrolled. I have no knowledge of the high/low pressure with the feeds on top of the head - the only high pressure I"m aware of is fed to the sides of the head.

In fact, I have an Atlas head like that looking for a home as I'll never have a use for it!

marshg246 said:

The flats I'm talking about have the oil hole in them and the spindles are not scrolled.

Click to expand...

Early high pressure spindles apparently had no flats only the oil hole. This type is no longer available.
Later type.

marshg246 said:

I have no knowledge of the high/low pressure with the feeds on top of the head - the only high pressure I"m aware of is fed to the sides of the head.

Click to expand...

The high pressure rocker feed was introduced from 116372 (during 1966) so before Commando (and before the side feeds).

L.A.B. said:

The high pressure rocker feed was introduced from 116372 (during 1966) so before Commando (and before the side feeds).

Click to expand...

OK, good to know. Is there a definitive place that talks about the combinations of spindles, pressures, feed locaitons, etc.? If not, could you be convinced to make one and put it in resources?

Some of the Commando heads I work on have them wrong so I know it's confusing to people even though the Commando workshop manuals are clear.

marshg246 said:

Is there a definitive place that talks about the combinations of spindles, pressures, feed locaitons, etc.?

Click to expand...

I don't know although it has been discussed before. If 116372 or later then it should be high pressure regardless of the head feed position and have unscrolled spindles.

marshg246 said:

If not, could you be convinced to make one and put it in resources?

Click to expand...

No, as there's no more information available that I'm aware of.

L.A.B. said:

I don't know although it has been discussed before. If 116372 or later then it should be high pressure regardless of the head feed position and have unscrolled spindles.



No, as there's no more information available that I'm aware of.

Click to expand...

So, does the oil hole in the spindle, not matter which type, face away from center in all high pressure and towards center in all low pressure? Sorry, I stuck my nose where it does not belong and now just want to know so I don't confuse anyone else in the future!

marshg246 said:

So, does the oil hole in the spindle, not matter which type, face away from center in all high pressure and towards center in all low pressure?

Click to expand...

High pressure the hole (with or without flat) should face out.

Low pressure shows the flat on the inside but not the position of the oil hole as it's not in the flat.

marshg246 said:

I should have stayed out of it. I know almost nothing about pre-Commando. I was just trying explain why the feed was away from the hole in the rocker.

L.A.B provided much more info about the "flats". The flats I'm talking about have the oil hole in them and the spindles are not scrolled. I have no knowledge of the high/low pressure with the feeds on top of the head - the only high pressure I"m aware of is fed to the sides of the head.

In fact, I have an Atlas head like that looking for a home as I'll never have a use for it!

Click to expand...

No problem. Thanks

Ok all I know what to do now! One last question. What is the purpose of the flat? Have anything to do with the delivery and velocity of the oil? Got to tell you this Forum has proven invaluable in aiding me with this build. Thanks everybody

From what I have read, the flats are there to collect oil to improve lubrication to that area of the spindle.

Someone please correct if wrong.

marinatlas said:

Scrolled rocker spindles

Hi all,I'm sure this has probably been discussed before but mine are a little different. This is for my dominator 99. Low pressure oil feed from tank return. My scrolled spindles have NO flats, just the hole with a 2mm X 1.5 deep approx trough 360 degree around spindle. I suspect aftermar...

www.britbike.com

Hope that will help ...

Click to expand...

After reading this link, why is it that Dynodave says he would never put plain ( no flats) spindles in his engine? I guess I don’t fully understand. What exactly is a “scrolled” spindle?

jms said:

After reading this link, why is it that Dynodave says he would never put plain ( no flats) spindles in his engine? I guess I don’t fully understand. What exactly is a “scrolled” spindle?

Click to expand...

This is a scrolled type spindle https://images.app.goo.gl/hqykyEvRbsSrcjy3A

So here's my final thought now that I know which way they should face. Assuming the plain spindles that I have with no scrolling, and no flats, coming from a 1967 Atlas, was there a problem with these or should I be replacing them with non scrolled with flats type. It is a high pressure set up

If I was you new one plain ( with flat of course) , at least they will be new !

jms said:

So here's my final thought now that I know which way they should face. Assuming the plain spindles that I have with no scrolling, and no flats, coming from a 1967 Atlas, was there a problem with these or should I be replacing them with non scrolled with flats type. It is a high pressure set up

Click to expand...

IMO, the scroll and flats were to enhance oiling to the rocker bores and thence to the pushrods when the source of the oil was from the low pressure scavenge oil return. In the low pressure system, the oil pressure feeding the rockers is that necessary to lift oil from the bottom level of the oil tank to the upper level and thru a small hole restriction, a few psig at most.
In the high pressure system, oil is fed to the rockers at the same pressure as fed to the crank big ends, anywhere from 5 to 60 psig, depending on engine rpm and oil temperature. Obviously, way more pressure than that of the low pressure system.
Thus, the high pressure system is capable of delivering much more oil to the rocker boxes than the drainage system was ever designed for, and the oil supply enhancements of the scrolls and flats results in flooding of the rocker boxes.
The earliest solution to control over oiling the rockers was to reverse the flats. IMO, after Norton exhausted their inventory of scrolled and flatted spindles, it became obvious they could save machine costs by going to a plain spindle. Thus, your spindles are not likely to be problematic. To allay any fears, pull the rocker box covers after a run and visually check for oil. The least pooling of oil is sufficient.

Slick

I would use Commando style spindles that have flats for high pressure applications.

kernel65 said:

I would use Commando style spindles that have flats for high pressure applications.

Click to expand...

A solution without cause for concern, as the final iteration in the evolution of the spindles should include all that Norton learned about this matter.

jms said:

So here's my final thought now that I know which way they should face. Assuming the plain spindles that I have with no scrolling, and no flats, coming from a 1967 Atlas, was there a problem with these or should I be replacing them with non scrolled with flats type. It is a high pressure set up

Click to expand...

It would not hurt a thing to use new plain spindles with the flats. Just face the flats away from the center of the head.

That is how the head in my '67 Norton 750 engine is set up and I do not have an over oiling issue. Spindles with flats are what came in '67 750 engine heads when they were built new if one is to believe the instructions in the Norton Villiers manual I have that was first published in March 1967.

I'm not sure why Dunstall used the plain spindles in the head unless that is all they had laying around the day they put it together.