Speedo cable wrapped around axle

L.A.B.

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2nd. link moved to a later post.
 
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Its too late to take the wheel out and show a photo - not sure I'm able to post photos anyway. Try tomorrow.
Re the drawing - see the direction of the worm drive - its drawn across the oil filter clamp, not along the clamp as it has to be to work. Just an example of a small error in the drawing
Just pulled it and you are correct - the bearing spacer 7704 accepts the top hat to engage with the axle and I assume the inner bearing spacer 2069 engages the axle with the wheel bearing.

So that part of my argument, about providing a sleeve to engage the axle to the wheel bearing, is wrong. The purpose of the top hat when fitted into the bearing spacer 7704 is to provide a small extra spacer to prevent the speedo drive being distorted as the axle is tightened and to hold the speedo drive off the hub cover.
 

marshg246

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The purpose of the top hat when fitted into the bearing spacer 7704 is to provide a small extra spacer to prevent the speedo drive being distorted as the axle is tightened and to hold the speedo drive off the hub cover.
The speedo drive must be a snug fit on the axel so it runs true. Triumph and BSA used speedo drives with the right sized hole. The Norton speedo drive has a hole larger than the axle so the top hat (06.7629) is used to correct for that. Then, the spacer (06.7704) between it and the bearing has to be the right length so that the speedo drive engages the drive dogs without binding. Then the outer spacer has to be the right size to take-up the gap between the speedo drive and swingarm.

*EDIT* I went back an added part numbers. There are three parts in the rear wheel that some call "top hat". That's not the correct name for any of them.
06.7629 SPEEDO DRIVE SPACER (NM13270) (B2/660) (Thru speedo drive)
06.7704 SPACER (NM18234 - K12-2/441) (Between speedo drive and bearing)
06.5290 BEARING SPACER - LH (06.2070) (Drum bearing spacer)
 
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Lineslinger

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Just pulled it and you are correct - the bearing spacer 7704 accepts the top hat to engage with the axle and I assume the inner bearing spacer 2069 engages the axle with the wheel bearing.

So that part of my argument, about providing a sleeve to engage the axle to the wheel bearing, is wrong. The purpose of the top hat when fitted into the bearing spacer 7704 is to provide a small extra spacer to prevent the speedo drive being distorted as the axle is tightened and to hold the speedo drive off the hub cover.
i27ytx.jpg
 

L.A.B.

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The purpose of the top hat when fitted into the bearing spacer 7704 is to provide a small extra spacer to prevent the speedo drive being distorted as the axle is tightened and to hold the speedo drive off the hub cover.

It won't, as there would be no additional contact area with the top hat on the inside because the O/D of the top hat flange is approximately the same as the inner spacer and the hole in the speedo drive gearbox is also larger than the I/D of the top hat flange.


The purpose of the 06.7629 top hat spacer is to centre the larger (0.687") hole of the drive gearbox* as marshg246 says (also texasSlick in the link below) therefore, should be on the outside of the drive gearbox as shown on the factory drawing and the one in Lineslinger's post.


*(The BG5330/171 drive gearbox is the same as used on the Triumph T140 etc. that has an axle that fits the hole).
 
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It won't, as there would be no additional contact area with the top hat on the inside because the O/D of the top hat flange is approximately the same as the inner spacer and the hole in the speedo drive gearbox is also larger than the I/D of the top hat flange.


The purpose of the 06.7629 top hat spacer is to centre the larger (0.687") hole of the drive gearbox* as marshg246 says (also texasSlick in the link below) therefore, should be on the outside of the drive gearbox as shown on the factory drawing and the one in Lineslinger's post.


*(The BG5330/171 drive gearbox is the same as used on the Triumph T140 etc. that has an axle that fits the hole).
Its time to agree to disagree here.
I'll put the wheel back in now and have a nice ride in the sunshine.
 

Tornado

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You should be seeing a similar length of inner when pushed fully into the sleeve as my previous pic.
Again, here:

I'd say there should be a minimum of 3/8" protruding because at least 1/8" of the engagement is lost as the spindle doesn't extend to the very bottom of the gauge but only as far as the brass ring in the pic below:
Ok had it off the bike and discovered to speedo end of outer sleeve had come off the rest o the cable sleeving plastic, which meant any amount protuding from driven end would be much shorter.
Was able to crimp both end sleeves more securely to plastic sleeve. This gave me 5/8" protruding at drive end when speedo end fully seated. Reconfirmed my drill gave good needle movement with this arrangement, inner being pushed up into speedo end as I ran drill.

Back on the bike and wheel spin does now give a flick on needle. Cannot get enough wheel spin by hand on CS to give more consistent needle movement so full test needs to await return of dry weather.
Gives me some days to work on other items like re-torquing head bolts; re-wiring my SparkBright LED voltage warning; valve lash check; adjusting rear wheel offset and fitting fresh tire.
This bike never seems to be done ;-)
 
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