Tapered Shaft Motor Sprocket Issue

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gitguy
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Tapered Shaft Motor Sprocket Issue

#1

Post by gitguy »

What's wrong with this picture? With the sprocket fit to shaft the sprocket nut doesn't even come close to tightening completely with almost 1/4 inch of thread still visible. I was told that some of these aftermarket sprockets are machined incorrectly. Anyone have any insight to this?
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rozemab
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Re: Tapered Shaft Motor Sprocket Issue

#2

Post by rozemab »

You're hung up on the woodruff key. If possible try and remove the key and test fit.

If I recall correctly, the key is rounded on one side to 'rock' as the sprocket is slipped onto the taper.

Do NOT attempt to run your panhead in that state !
gitguy
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Re: Tapered Shaft Motor Sprocket Issue

#3

Post by gitguy »

I answered my own question. Looks like I ended up with a 45 sprocket - d'oh!
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Re: Tapered Shaft Motor Sprocket Issue

#4

Post by RUBONE »

45 sprockets have totally different teeth on them, and that isn't one. It looks like you got a crappy aftermarket Big Twin one.
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Re: Tapered Shaft Motor Sprocket Issue

#5

Post by rozemab »

1950EL
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Re: Tapered Shaft Motor Sprocket Issue

#6

Post by 1950EL »

I was unable to find an OE 24 tooth and tried three different aftermarket sprockets with bad tapers. I got lucky enough to find a guy to machine a new taper on one of the new junk sprockets to match the taper on my sprocket shaft. Good luck.
Mike
gitguy
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Re: Tapered Shaft Motor Sprocket Issue

#7

Post by gitguy »

rozemab wrote:You're hung up on the woodruff key. If possible try and remove the key and test fit.

If I recall correctly, the key is rounded on one side to 'rock' as the sprocket is slipped onto the taper.

Do NOT attempt to run your panhead in that state !


The key is not installed. This is just a mock up. The tapered shaft is clean with no burrs or oil. I think it is just a crappy aftermarket sprocket . . .
Thanks for the input. Will search for a different sprocket.

Oh well!
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Re: Tapered Shaft Motor Sprocket Issue

#8

Post by Izh Kabob »

My pan was an early 1952. The taper on the output shaft changed in late 52 or 53
Seems one was actually straight shaft. and the sprockets while possibly machined correctly for the year may not cross over early to late or with previously substituted parts. I had the same problem and my mech showed me the difference. He also provided correct(for the shaft motor sprocket in trade).
I also had aftermarket or modified flywheels. Had to time off the rear cylinder mark instead of front as book said.
Found the note from my mech after 2nd knee surgery. :D

Cheers,
Harry
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Re: Tapered Shaft Motor Sprocket Issue

#9

Post by RUBONE »

My pan was an early 1952. The taper on the output shaft changed in late 52 or 53
No, it did not. The tapered shaft used by H-D was unchanged from 1930 to 1954 where it ended at the end of the model year to be replaced by the splined shaft used from '55 up. All sprockets from '30-'54 interchange on the shaft on all '30-'54 Big Twin models. If your "mechanic" told you differently, you need a new mechanic...
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