Dynamo chain & final drive chain

[Guy Wilson]

Can anyone tell me if the dynamo chain is a standard size? Its part no. 67-296 . I?m wondering if I can buy a section of the shelf in Kenya. If I start talking about a 1954 BSA, its going to complicate the issue. 
Along the same lines, what?s the standard length and size of the drive chain part no. 42-9033? Its a swinging arm model and standard as far as I can tell.
Guy

[duTch]

Hiya Guy in Kenya, It's what I've always done,note the part # but may as well disregard,as no meaning to a chain shop? Best thing is take the chain and sprockets to the chain shop,count the number of rollers in each chain for lengths, but keep in mind a previous owner may have taken one out for a 'quick fix'. If you have manual it'll be there but I think the final drive is 5/8pitch x 3/8 wide,not sure on S/A primary,maybe 1/2p. x 3/8w? I could be thinking' of something else but have a funny feeling dynamo is metric ????  (8mm x ?) or 5/16 x 1/4(?), others can confirm/challenge? Work to do now, hope that's helpful, duTch

[Goldy]

according to this site      http://britbike.com/    the dynamo is 8m x48r and final drive is 5/8" x 3/8" x100 - 102.   all the best Goldy

[Guy Wilson]

Thank you! that I can do on the phone, assuming they're working that is...
Guy

[duTch]

Thanks Goldy,

[bikerjohndavies]

Hi Guy, The Draganfly site lists all the different chain sizes and number of links for the primary and drive chain.

http://www.draganfly.co.uk/shop/pi1694906175.htm?categoryId=764

The dynamo chain is endless 8 X 3MM with a length that is 48 links for the upto 1950 long stroke A7 and 52 limks for the A10 and later short stroke A7 engines.

[trevinoz]

Bikerjohn,
                     I think that you will find that the early engine has the long chain due to the larger dynamo sprocket.

  Trev.

[bikerjohndavies]

Hi Trev, not on my 1949 A7. The longer 52 link chain ment that the dynamo chain could not be tightend as the sprocket hit the inner timing case. The shorter chain 29-2199 (48) links is listed in my 1949 parts book.

[trevinoz]

It depends on which dynamo is fitted, Bikerjohn.

If the long E3L is fitted, it should have an 11 tooth sprocket and the short E3H should have a 13 tooth.

Trev.