Removing '47 G80 dynamo

strider · Post by **strider** » Fri Sep 21, 2012 10:30 pm

According to "The book of the AJS Singles 1945-56", the dynamo is removed by slacking of the gearbox adjustment and swinging it to the rear, and sliding the dynamo out to the off side.
But on the AJS there is no magneto in the way.
Is it easy enogh to get at the dynamo clamp without disturbing the Magneto on the G80, or is it just easier to remove carb and magneto to get at the dynamo?
I have already detatched the dynamo chain & sprocket.

Rob Harknett · Post by **Rob Harknett** » Sat Sep 22, 2012 1:00 am

For 1947, having got as far as getting the dynamo sprocket off, all you should need to do is " slacken" of the clamp bolts to remove the dynamo

strider · Post by **strider** » Sat Sep 22, 2012 9:10 am

Thanks Rob. I'll try that.

Rob Harknett · Post by **Rob Harknett** » Sat Sep 22, 2012 9:54 am

Note when refitting the dynamo shaft is or is on my bikes, off centre. so can be rotated to fit the chain then rotate to tighten & clamped. This may alter the setting, so try again guessing how much it will alter when tightend to get the chain tension correct.

strider · Post by **strider** » Sat Sep 22, 2012 11:13 am

Yep! It came out Ok. The only bit that I didn't reckon on was the bent metal strip, screwed to the dynamo body, between the engine plates, presumably to ensure correct alignment for the drive chain.
A damn good clean of the necessary area revealed all!

Rob Harknett · Post by **Rob Harknett** » Sat Sep 22, 2012 11:57 am

correct about the strip, I almost mentioned it but did not.
Assume all the correct parts held the sprocket on , in particular and in good condition the locking spring that goes on the special nut last, locking tab washer it holds on.
If you are checking a 1947 parts list you will see, in order they go on, washer plain pt. no. STD10, nut STD 611, washer locking STD 164, ring locking STD 708, if you need to order these parts from club spares, covert those numbers to new pt. no. by deleting the STD prefix then prefix with enough zero's to make a 6 digit number.

strider · Post by **strider** » Sat Sep 22, 2012 12:21 pm

Thanks Rob, but I'm replacing the dynamo with an Alton. It has a parallel shaft and a key.

Rob Harknett · Post by **Rob Harknett** » Sat Sep 22, 2012 12:28 pm

Don't know about those Peter, the original dynamo has a woodruff key also tappered as you may well know. What prevents the nut coming off the Alton? also has it a stop tab.

Rob Harknett · Post by **Rob Harknett** » Sat Sep 22, 2012 12:51 pm

I have just read the Alton thread. Sprocket is held on with allen screw. Nothing to stop it working loose?
Just a note on the insurance bit, mods or extras not declared would not be covered and may invalid insurance. My mods and extra's declared are stated on my insurance. If new law outlaws non standard parts here no way out but to comply with the law. So again even if the insurance are OK with a mod, your machine would not be road legal.