Atlas Drive Side Crankshaft Thread

[jms]

Hi
Can anybody confirm that the Atlas drive side crank thread is 5/8”-20 BSC and that it is the same thread as the gearbox drive side mainshaft. Thanks

 

[Schwany]

The same thread is used on the crank end for the alternator rotor and to hold the clutch hub and basket on the gearbox mainshaft. I've cut the shoulder off of the nut that holds the rotor on the end of the crank and used the thinner nut on a NEB clutch. I'm not sure about the 5/8-20 BSC spec, but they are the same thread.

 

[jms]

The same thread is used on the crank end for the alternator rotor and to hold the clutch hub and basket on the gearbox mainshaft. I've cut the shoulder off of the nut that holds the rotor on the end of the crank and used the thinner nut on a NEB clutch. I'm not sure about the 5/8-20 BSC spec, but they are the same thread.

Thanks Schwany. I was making an adapter that will allow me to bolt up a degree wheel to the crank with bolt that I have

 

[jms]

Thanks Schwany. I was making an adapter that will allow me to bolt up a degree wheel to the crank with bolt that I have

Don’t you need the shoulder to steady the rotor?

 

[Schwany]

Don’t you need the shoulder to steady the rotor?

Having owned and worked on my Norton for over 50 years as well as many other motorcycle brands over the course of my lifetime I had enough common sense to have another new rotor nut handy before cutting up the old one. Would be kind of nutty not to be prepared.

After cutting the shoulder off the older rotor nut, I used the thinner remaining nut to hold the NEB clutch hub on the gearbox mainshaft.

The example I gave was supposed to help verify that the threads are the same on the drive side end of the crank used to hold the rotor on a Norton that is using an alternator and the AMC gearbox mainshaft, or whatever gearbox one is using that is designed for use on a old Norton. Apparently I failed