Front Pulley Issues

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Have you tried a standard Norton front engine sprocket ( a known good example ) on the crankshaft taper to confirm it is the shaft's taper is the problem it maybe that the belt pulley internal taper is incorrect ? That key is sus if it falls out .
 
Have you tried a standard Norton front engine sprocket ( a known good example ) on the crankshaft taper to confirm it is the shaft's taper is the problem it maybe that the belt pulley internal taper is incorrect ? That key is sus if it falls out .

Like I said it fit perfectly on the other crank. I don’t know where a standard sprocket is, probably buried. I’ll see if I can find one.

New key on the way from Old Britts.
 
interesting situation...

i just put my primary back together. i can't recall any specifics about the key but my old one was a sloppy fit and it looked like somebody had been filing on it. so i ordered a new one. the new one was not a tight fit in the shaft... so how tight are they suppose to be (thats the part i can't remember)...

thanks
 
interesting situation...

i just put my primary back together. i can't recall any specifics about the key but my old one was a sloppy fit and it looked like somebody had been filing on it. so i ordered a new one. the new one was not a tight fit in the shaft... so how tight are they suppose to be (thats the part i can't remember)...

thanks

I believe the primary purpose of the key is to locate not hold the pulley/sprocket. The taper and nut should do the actually holding.

Anyone want to correct me?
 
Snug fit for keys. Not drive fits. One doesn't want them to chatter with vibration. Some applications use wedged keys or shimmed keyways to lock auxiliary items onto shafts to prevent movement. So many ways to screw a pooch that it boggles the mind.
 
Snug fit for keys. Not drive fits. One doesn't want them to chatter with vibration. Some applications use wedged keys or shimmed keyways to lock auxiliary items onto shafts to prevent movement. So many ways to screw a pooch that it boggles the mind.

I’m glad I’m not a pooch.
 
Is there enough material on the pulley, and enough width for the belt, to face the back of the pulley down the make the taper effectively smaller? Would be an simple turning job
 
Is there enough material on the pulley, and enough width for the belt, to face the back of the pulley down the make the taper effectively smaller? Would be an simple turning job

Interesting approach. The belt width is exactly the same as the pulley so you can't reduce the pulley width. At the front there's not a lot of room.
 
Interesting approach. The belt width is exactly the same as the pulley so you can't reduce the pulley width. At the front there's not a lot of room.
What width is the pulley/belt width?
With the norvil kit I believe you can run a 32 mm or 30 mm belt on a 32mm wide pulley, I'm not certain on this though
Cheers
 
I dont think myjota means the whole back face of the pulley, just around the hole where it mounts.
 
I believe a beer can will be too thick.

Average beer can wall is 0.004. That's pretty thin unless you still have some steel cans around. I'm a big believer in creative play, but mostly I like the idea of having a beer while pondering how to sort out the problem.
 
Average beer can wall is 0.004. That's pretty thin unless you still have some steel cans around. I'm a big believer in creative play, but mostly I like the idea of having a beer while pondering how to sort out the problem.

Is there an advantage to brass over aluminum in this case?
 
Brass is most suitable of the two. Aluminum is soft by comparison. Steel would be best.
 
Is there enough material on the pulley, and enough width for the belt, to face the back of the pulley down the make the taper effectively smaller? Would be an simple turning job

Good idea and if facing off the back made it fit but left it too narrow then the outer guide plate could be shimmed to give the width back. Just an idea, or would it throw up other issues?
 
Good idea and if facing off the back made it fit but left it too narrow then the outer guide plate could be shimmed to give the width back. Just an idea, or would it throw up other issues?

Overly complex compared to shoving crap in the gap or getting a blank pulley machined to the right taper.
 
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Don't you folks the other side of the pond still have food in tins/cans? They are mostly still steel. Baked bean cans have provided me with the odd steel shim over the years.

Aluminium wouldn't be tough enough I reckon.

Ian
 
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