Dynamo Help

Don Madden · Post by **Don Madden** » Tue Jul 28, 2009 3:35 am

Birmingham spanner? I think it is the same as a Harley adjustable, fits all. Some call it a 2lb lump hammer, but what do they know?

Cheers, Don.

One pot · Post by **One pot** » Thu Jul 30, 2009 10:19 pm

Hi Shaun,
Just a word of warning if you try to do this on the bike. If there is any wear in the locating pegs (or their corresponding holes) the dynamo can be assembled with the armature slightly out of alignment, it may then contact the pole shoe and cause big problems. This would be quite difficult to diagnose if it were not possible to spin the Dynamo freely.

Good Luck

One Pot

rainmanshaun · Post by **rainmanshaun** » Sat Aug 01, 2009 6:02 pm

Thanks One Pot - I get the feeling that I will be taking the Dynamo out and stripping it down to give it the once over anyway ! I have bought some nice BA box spanners on Ebay which I will probably have to grind down a little to fit and I am now armed with some Thread Lock so now just need to allocate some time to get it done along with all the other tasks remaining - one of them being the re-sealing of the dreaded Tin Chaincase ! It very handy that the "Itma Answers" article this month was on doing this job right so I shall follow his instructions. At least I am not missing out on lovely sunny riding weather What happened to that "Hot Summer" that we were promised ????

rainmanshaun · Post by **rainmanshaun** » Sun Aug 02, 2009 4:57 pm

Ok so can anybody tell me which tool I need to pull the Dynamo sprocket off the shaft ? Do I need to remove the primary chain to do this or can it be done with it in place ? I don't appear to have any kind of locking device and the end of the nut is chewed up and looks like it may have been a lock nut once ! Looking at the pictures in the archives perhaps I don't have an original dynamo/sprocket set up.

I would imagine I will need a small puller to get the sprocket off....

rainmanshaun · Post by **rainmanshaun** » Sun Aug 02, 2009 6:18 pm

Now have managed to get the Dynamo sprocket off my 57 G3LS and have got the dynamo out. The shaft has a woodruff key slot but the key was missing. The sprocket looks suspiciously like a magneto drive sprocket (17 teeth) as there are no slots for a lock washer.

The Dynamo looks like it might be the wrong one as it is stamped with E3H - AC33...

To top it all I discovered that the crankshaft sprocket could be moved slightly clockwise/anti clockwise on the crank even with the nut done up and the lock washer turned over. It looks like the centre of the sprocket has been built up at some time and the splines re cut (badly !) So I am now looking for the correct dynamo/sprocket/locking assy and a crank drive sprocket

wilko · Post by **wilko** » Mon Aug 03, 2009 2:54 am

Normally the sprocket has no splines, it is free to move to&fro within the constraints of the spring pressure and the splined cam at the end? Maybe this is what you mean?

rainmanshaun · Post by **rainmanshaun** » Mon Aug 03, 2009 9:46 am

Hi Wilko - I think you are referring to the shock absorber version fitted to models earlier than '57? Mine doesn't have this set up and the Sprocket slides on to the drive side axle of the crank which has 4 splines. The splines on the crank look ok but I think that someone in the past has had the centre built up and re machined the splines. I think that it should be a good fit on the shaft with no radial play even without tightening up the nut. I will investigate getting a second hand sprocket as new ones don't seem to be available for this later set up.