torque setting........lower steering head nut

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is it wise to tighten down the big nut on the bottom of the steering head at the lower yoke without the use of a torque wrench.....not having one available at the moment....what would be the ideal way of tightening this down?
regards,
SpitfireRick (Eric)
 

L.A.B.

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I just tighten the nut with a normal wrench/spanner and knock over the lock washer, as the later type bearings are standard sealed ball bearings instead of the (rather more normal) cup and cone or taper bearing arrangement then I don't believe the preload needs to be that critical, the standard torque setting being only 30 ft/lb.


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Actually there really isn't any 'preload' on the bearings from the nut torque as the yoke/bearings/internal spacer assembly is just pulled down tight.
 
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L.A.B.
I was thinking the same thing, when we went to remove it......wasn't all that tight anyway and the torque wrench available was busted, so we tighten it down then folded the washer over.
thx,
SpitfireRick

L.A.B. said:
I just tighten the nut with a normal wrench/spanner and knock over the lock washer, as the later type bearings are standard sealed ball bearings instead of the (rather more normal) cup and cone or taper bearing arrangement then I don't believe the preload needs to be that critical, the standard torque setting being only 30 ft/lb.


-----------------------------
Addition

Actually there really isn't any 'preload' on the bearings from the nut torque as the yoke/bearings/internal spacer assembly is just pulled down tight.
 
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If you have the later taper rollers (Mk3 850) 30ft/lbs will tighten up the steering too much. Doesn't seem much but I never had my tapers come undone and I never bend over the tab washer, just a drop of threadlock.
Spec on post 71 is 15lbs only and the book says 40lbs for pre 71. Not sure why the difference for early to late ball types but the taper type did not come in until the Mk3 I think.
 

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Keith1069 said:
If you have the later taper rollers (Mk3 850) 30ft/lbs will tighten up the steering too much.

Commandos were not fitted with taper roller head bearings as standard, not even the 850 MkIII.

The standard head bearings used on Commandos (except early models) are the Norton part number 06-7604, which is a 6205 2RS 25x52x15mm type. This bearing is a = single row deep groove BALL bearing.


Doesn't seem much but I never had my tapers come undone and I never bend over the tab washer, just a drop of threadlock.

As the 6205 bearings (which maybe you do not have?) are ball bearings there is no range of adjustment, the nut is just tightened down, this clamps the top yoke/dust cover/upper bearing centre spool/spacer tube/lower bearing spool/lower yoke/lockwasher together.


Spec on post 71 is 15lbs only and the book says 40lbs for pre 71.

You appear to be quoting from the Haynes manual, however the factory manuals give the figure for '71-on as 30ft/lb. Pre-'71 models have cup and loose ball bearings with an adjuster nut and lock nut (at the upper end).


The Haynes manual says: "The bolts should be tightened to a torque setting of 40 ft lb and the steering head nut to 15 ft lb (1971 and later models ONLY)."

If that is the '40 ft lb' you are referring to, then isn't it referring to the fork cap bolts?
As the paragraph deals with reassembly as well as adjustment (although the factory manual says 30 ft/lb for those bolts -the Haynes book possibly getting that torque setting wrong by quoting the Dominator figure of '40' ft/lb?



Not sure why the difference for early to late ball types but the taper type did not come in until the Mk3 I think.

Perhaps if you do have a copy of the Haynes manual may I draw your attention to "Steering head bearings -examination and adjustment" where it says: "Pre-1971 models have ball journal bearings which can be adjusted, whereas later models have bearings of the non-adjustable type."

I have an 850 MkIII and it does not have taper head bearings, but the normal 6205 type (that are still supplied as the correct replacement parts).

Some info on Norton head bearings and conversion to taper rollers here (although I do not personally see why anyone would want to bother -not for '71-on models at least):
http://www.nortonownersclub.org/technic ... etail.html
 
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L.A.B. You are absolutely right. I have both manuals and it was the Haynes I laid my hands on. Apologies for mis-direction. Mine is a Mk3 850 frame and clearly the PO had done the conversion.
 
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Hi All,

Reading this has prompted me to ask a question I have pondered for a while. Why do you bend the tab washer over when it doesn't locate on anything, ie, there is no tag that locates the inside of the washer in the spindle etc. Surely it is not just the friction that stops the washer from turning??
 
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you are right there is no locating spindle or flat side, but what i believe is that one end is tapped flat over the nut and another part is flattened in the opposite direction over the lower steering yoke......essentially, one up and one down. this keeps it from loosening.

SpitfireRick (Eric)


Reading this has prompted me to ask a question I have pondered for a while. Why do you bend the tab washer over when it doesn't locate on anything, ie, there is no tag that locates the inside of the washer in the spindle etc. Surely it is not just the friction that stops the washer from turning??[/quote]
 

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As SpitfireRick has said, one part of the washer is bent down against a flat on the nut and another part bent up between the webs of the lower yoke/triple tree which will stop the washer turning.
 
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