SRM Dynamo Belt Drive Alignment

[Superarnie]

Good morning to all,

I have almost finished a restoration on my 1960 Spitfire Scrambler. One of the last jobs before kicking it over, has been to fit an SRM belt drive on the dynamo. I'm having problems with the pulley alignment. There is about 2mm difference between the two pulleys. Can anyone offer any advice?
Many thanks
Gary

[Greybeard]

The dynamo can be moved in and out but just make sure the cork washer seals the gap.

[Swarfcut]

  Depends which way they need to move. As both pulleys are on fixed tapers, varying the thickness of the cork washer (mentioned by GB), if retained, offers a solution. Otherwise something slightly awry with the manufacturing tolerance and assembly of the new pulleys. Can they be tweaked?

 Swarfy

 Thinks......electrical system on a Scramble bike with magneto ignition? No, it's a Thorspark. Earlier posts also indicate dynamo rebuilt, an aftermarket armature could be the problem.

[Superarnie]

Thanks for the inputs fellas. It looks like the dynamo needs to move into the timing casing further to make up the 2mm. I will initially remove the thick Cork washer and take it from there. Thanks very much! As I say, the machine is nearly finished. I have done a full strip down restoration and am on the last stages. Here's a couple of images. Before you shout at me, I know there are some non stock/none original spec parts fitted. For example the seat will in time be replaced with a black piping cover; I have the original tank but it needs a new lining so until then, I have fitted an Indian built tank.
Regards
Gary

[Superarnie]

Sorry, struggling to attach images. I'll keep trying!

[Greybeard]

I guess that as you are fitting a dry running belt you don't need to worry about sealing the dynamo to the case but maybe a paper gasket or some silicone sealant to keep water and dust out would be an idea.

[Superarnie]

I've managed to get it within a millimetre and turned the engine over by hand with the plugs out. The belt looks to be fine and not riding up the pulley walls, in fact there seems to be a very small gap between the belt and pulley walls. I'll see how I get on! Thanks again. Can't seem to post any images; keep getting error message saying the file is too large. It's only one image but it doesn't like it.

[Greybeard]

I often have to use a software tool to reduce the size of pictures. If you are using a Microsnot machine you can use Paint.

[muskrat]

G'day Gary.
I run belts (not SRM) in both mine and found it best to run grease in there. The belts don't last long dry.
Cheers

[Superarnie]

G'day Muskrat,
I have put some grease in the cavity. I was unsure whether to as some members advise to run them dry, but I decided to follow the instructions that came from SRM and see how I get on.
Thanks again
Gary

[CheeserBeezer]

I've managed to get it within a millimetre and turned the engine over by hand with the plugs out. The belt looks to be fine and not riding up the pulley walls, in fact there seems to be a very small gap between the belt and pulley walls. I'll see how I get on! Thanks again. Can't seem to post any images; keep getting error message saying the file is too large. It's only one image but it doesn't like it.

Regarding images, I do a screenshot and paste into 'paint', crop the image, save as a jpeg, then post.

[Superarnie]

BSA1960 Spitfire Scrambler. Original frame and engine. I've put alloy flanged wheels front and rear, 19 front, 18 rear, rebuilt engine/gearbox. Head refurbished by Seager Engineering. Put Thorspark Electronic Ignition on and in doing so, fitted battery, ignition switch, 12v dynamo armature and new wiring harness.  SRM dynamo belt drive and sump plate. New pistons/rings, bearings seals etc. Powder coated frame. Tank came from India and will do for now. Seat needs correct spec fitting. Non stock handle bars fitted which i prefer. Nearly ready to fire up!!!.

[Superarnie]

Drive side image. Not happy with the exhaust pipe spacing, they're a touch too far apart for my liking. I'm waiting for the correct bracket to arrive from Australia but the one fitted will have to do for now.

[Superarnie]

Rear image. I put as wide a tyre as I could on the rear.

[Superarnie]

Front end image. I fitted a lighting kit similar to the kits supplied back in the day.
Should have it on the road soon!