Atlas Rocker Spindles

jms

jms

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Hi I'm back, Relative to the Atlas head. Had new guides installed, new valves, and recut seats and am putting the rocker gear back in and was wondering if it matters which way the oil holes in the spindles are facing, forward or backwards. It wouldn't seem to make a difference but just thought I would ask.
 
It does make a difference! And it may also depend on whether you have a low pressure top oiling system or high pressure. I would have to check with my Norton shop manual to be sure, but IIRC, the flats on the spindles should face toward each other (low pressure) and away from each other (high pressure). Don't do anything yet, I will check the manuals tomorrow and report back.

Slick
 
texasSlick said:
It does make a difference! And it may also depend on whether you have a low pressure top oiling system or high pressure. I would have to check with my Norton shop manual to be sure, but IIRC, the flats on the spindles should face toward each other (low pressure) and away from each other (high pressure). Don't do anything yet, I will check the manuals tomorrow and report back.

Slick
Click to expand...
Thanks Slick. I noticed in my 71 forward Commando workshop manual that the spindles had flats where the hole is however mine is a 67 Atlas ( I don't have a manual and need to get one) and my spindles are perfectly round with no flats. The rocker oil feed is fed from the time side crankcase just below the pressure valve and not taken off the oil return line at the tank so I assume that means high pressure. interestingly the 71 forward manual says nothing about the orientation of the flats / holes.... or at least that I could find. I'll wait on your findings. Thanks again
 
ok so when one refers to a scrolled spindle, that is synonymous with an obvious flat to the left and to the right of the oil hole? I've included a few photos of what I have. Think its a 6 start worm therefore a matching pump. Note the spindle. No flat at all
 

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And on to a related subject. I bought this bike completely dismantled and it was somewhat of a leap of faith relative to condition of things. As it turned out the crank was still standard and only about .002 out, valve guides where still cast iron and not terribly sloppy, pistons where flat tops ( so that had been changed), the bore was .003 from standard, the clock had 31,000 miles. I have no history on the bike other than it was a documented Dunstall bike that was purchased by the original owner from Dunstall. I got that from the Kensington Science Library before Norton archives were transferred to the NOC. Given all of these findings and assuming it’s all original, would one expect to rebuild an oil pump or would it have a lot more life.
 
jms said:
Thanks Slick. I noticed in my 71 forward Commando workshop manual that the spindles had flats where the hole is however mine is a 67 Atlas ( I don't have a manual and need to get one) and my spindles are perfectly round with no flats. The rocker oil feed is fed from the time side crankcase just below the pressure valve and not taken off the oil return line at the tank so I assume that means high pressure. interestingly the 71 forward manual says nothing about the orientation of the flats / holes.... or at least that I could find. I'll wait on your findings. Thanks again
Click to expand...

You have the high pressure system. I think 1966 was the change over year.
 
From what I understand, ~1967 was when the spindles with flats introduced. Very possible to have mixed parts in transition years.
 
Good topic. I am sure I did my rebuild right but in my startup and first few miles I am nervous, how much oil should be in the top end? It seems pretty dry up there.
 
I’ve observed rockers/valve springs with light coating, maybe some small pooling in low areas of the casting after letting it sit to cool. More intake side than exhaust.
 
jms said:
ok so when one refers to a scrolled spindle, that is synonymous with an obvious flat to the left and to the right of the oil hole? I've included a few photos of what I have. Think its a 6 start worm therefore a matching pump. Note the spindle. No flat at all
Click to expand...
Scrolled would be similar to the shallow grooves cut into the cam where the cam fits into the bushes. The flat is as you describe, but not scrolling. You do have a 6 start, and as mentioned a higher pressure set up.

I'm not sure about the need to replace the oil pump. They are pretty tough, simple, and can last as long as a lot of grit has never gone through them.
 
Reference: Norton Twin Cylinder Manual. NOTE! ... no publication date on this document!

"Both rocker axles have a flat machined on one side- they are identical. These flats are for the oil pickup- and both axles should be fitted with the flats facing inwards {towards the center of the head ). ...... Note carefully the location of the slot in the axle- which must register with the projection on the retaining plate."

IMO, this service note applies to low pressure systems ONLY!

My notes: Spring washer is inboard, thrust washer is outboard.

In your case, not having flats on the axles (spindles), the latter condition regarding the slot registration with the retaining plate , may the the determining factor for the proper axle orientation.

Slick
 
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I think the flats should be facing outwards , exhaust flat looking towards the front of the bike and inlet flat looking towards the rear of the bike ......
 

Rocker spindle orientation which way? Am I an Idiot?

So after my recent short ride ended by dunstall fiberglass resin in my carbs i also found i consumed a lot of oil in a short time, compression was 120 cold, so not bad, plugs were black and stick in the cylinder came up oily black so ... pulled the exhaust pipe black soot and lots, pulled...
www.accessnorton.com www.accessnorton.com
 
marinatlas said:
I think the flats should be facing outwards , exhaust flat looking towards the front of the bike and inlet flat looking towards the rear of the bike ......
Click to expand...
Yikes, I could be an idiot!! That is what my P11 Red Maintenance and Instruction Manual says. Should have looked before speaking. Now I'm starting to wonder how I actually did reinstall the spindles. I don't have an oiling problem up top. So maybe I did install them facing away from the center.

Edit: My Haynes Atlas and Commando manuals say the flat on the spindles must face the rocker covers. I underlined it in the manual, so that is probably how I did it.

Anywho, all three of the Norton service manuals I have say flats away from the center. My confusion is with the smooth no-flat spindles. Clueless I am. I apologize for spreading any misinformation. I'll go stand in the corner now as penance.
 
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I cannot find any reference to spindle orientation in high pressure systems but IIRC, they are to be installed reversed from low pressure systems, that is, flats facing away from each other or outwards.

Slick
 
texasSlick said:
I cannot find any reference to spindle orientation in high pressure systems but IIRC, they are to be installed reversed from low pressure systems, that is, flats facing away from each other or outwards.

Slick
Click to expand...
Thanks I 'm thinking about your answer, which I appreciate, and am wondering why that would be given that each rocker bore has a small lubrication hole that leads to the pushrod cup. You would think that the spindle hole would want to be facing the hole in the rocker bore.
 

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 www.britbike.com

Hope that will help ...
 
jms said:
Thanks I 'm thinking about your answer, which I appreciate, and am wondering why that would be given that each rocker bore has a small lubrication hole that leads to the pushrod cup. You would think that the spindle hole would want to be facing the hole in the rocker bore.
Click to expand...
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.
 
texasSlick said:
I cannot find any reference to spindle orientation in high pressure systems but IIRC, they are to be installed reversed from low pressure systems, that is, flats facing away from each other or outwards.

Slick
Click to expand...
70-73 Workshop manual 065146, section C8:

Atlas Rocker Spindles
 
Flats on low pressure (scrolled) spindles should not be confused with the flats on high pressure (plain) spindles.
Different low pressure types.
www.accessnorton.com

Rocker Shaft Orientation

*Not only did I see the article in RH, but I observed the conversation on the forum. The lack of clarity between when the low pressure system and high pressure system were being rationalized. did not help at all. the hole in the ball end and thus the drilling in the rocker is shut off for a...
www.accessnorton.com www.accessnorton.com
 
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