Author Topic: Dynamo chain  (Read 342 times)

Online Superflash

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Dynamo chain
« on: 23.01. 2021 04:57 »
So....went to put the dynamo chain on and it looks to be an inch or 2 too short. Question is.. are there different chain lengths or have I missed a trick somewhere? Cheers
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Offline Slymo

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Re: Dynamo chain
« Reply #1 on: 23.01. 2021 05:44 »
Looks like a big sprocket on the generator side maybe?
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Online RichardL

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Re: Dynamo chain
« Reply #2 on: 23.01. 2021 05:47 »
Appently, you have the chain for the 11 tooth dynamo sproket , while yours is 13.

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Re: Dynamo chain
« Reply #3 on: 23.01. 2021 06:13 »
Thanks for the info. I see Mike's classics has a 52 link chain. Mine is 48 and with the 13 tooth dyno sprocket me thinks that be the problem.  Is there any reason why I can't use the 13 tooth sprocket? Cheers
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Online RoyC

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Re: Dynamo chain
« Reply #4 on: 23.01. 2021 08:26 »
  Is there any reason why I can't use the 13 tooth sprocket? Cheers

Just means that your dynamo will run a little slower.
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Offline Swarfcut

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Re: Dynamo chain
« Reply #5 on: 23.01. 2021 09:03 »
 Other possible is that the chain is the shorter A7 Longstroke type, in combination with the wrong dynamo sprocket.

 Swarfy.

Offline Rookie_V#60

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Re: Dynamo chain
« Reply #6 on: 23.01. 2021 09:38 »
  Is there any reason why I can't use the 13 tooth sprocket? Cheers

Just means that your dynamo will run a little slower.

Ok will be 18 % slower, I don't think you can neglect that.
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Re: Dynamo chain
« Reply #7 on: 23.01. 2021 10:01 »
Thanks guys. Pretty much just as I thought. So have tracked down an 11 tooth sprocket and a 52 link chain. Hey I see Mike from Mike's classics has got the business up for sale.....  *eek*
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Offline trevinoz

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Re: Dynamo chain
« Reply #8 on: 23.01. 2021 21:07 »
Have you got a long generator or a short?

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Re: Dynamo chain
« Reply #9 on: 24.01. 2021 03:16 »
It's 190mm. Imagine my surprise to find out there are long ones and short ones.  Then again why not..... *problem* nothing else is standard or simple with these bloody things.
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Offline trevinoz

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Re: Dynamo chain
« Reply #10 on: 24.01. 2021 20:22 »
Different type for different years.
The short 45W generator was used until 1948 or 49 and superseded by the long 60W generator.
Short has one pole screw and long two.
Short uses 13 tooth sprocket and long uses 11 with obviously different chains.