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Technical (Descriptive Topic Titles - Stay on Topic) => A7 & A10 Engine => Topic started by: MRedol on 22.12. 2025 15:55

Title: dynamo sprocket 11 tooth part No. 67-727
Post by: MRedol on 22.12. 2025 15:55
Hello,
Does anyone know where I can purchase within the UK the small dynamo sprocket 11 tooth part No. 67-727 for a Lucas E3L ?

I've looked online but I can only find it on back order.

Any help would be much appreciated!
Title: Re: dynamo sprocket 11 tooth part No. 67-727
Post by: berger on 22.12. 2025 16:54
there is a few on ebay and i have one knocking about in a box somewhere.
Title: Re: dynamo sprocket 11 tooth part No. 67-727
Post by: Billybream on 22.12. 2025 17:00
I will gave a look if I have a spare tomorrow morning for you
Title: Re: dynamo sprocket 11 tooth part No. 67-727
Post by: MRedol on 23.12. 2025 08:23
Thanks gents! Both sprockets I have look worn down and I’m getting tight spots on new chain. I’ve ordered the larger 27 tooth sprocket, but struggling to find the smaller sprocket.
Title: Re: dynamo sprocket 11 tooth part No. 67-727
Post by: Billybream on 23.12. 2025 12:12
Found a used one which came off my Super Rocket, looks decent to me, private message me if this helps, although if you can wait alittle longer, check out Priory Magnetos who has them in stock, Andrew the owner is a member on here.
Title: Re: dynamo sprocket 11 tooth part No. 67-727
Post by: CheeserBeezer on 23.12. 2025 12:57
Hello,
Does anyone know where I can purchase within the UK the small dynamo sprocket 11 tooth part No. 67-727 for a Lucas E3L ?

I've looked online but I can only find it on back order.

Any help would be much appreciated!
I stock these at Priory Magnetos, but you'll find that tight spots are inevitable with this setup. The culprit is more likely to be the drive sprocket which are nearly always eccentric.
Title: Re: dynamo sprocket 11 tooth part No. 67-727
Post by: MRedol on 23.12. 2025 14:22
Thanks for the info CheeserBeezer, maybe I'll see how the chain is once I've replaced the drive sprocket. Then I can decide whether to get the Dynamo sprocket replaced too. Where on your website is the small 11 tooth dynamo sprocket part No. 67-727 listed?

Regards
Title: Re: dynamo sprocket 11 tooth part No. 67-727
Post by: MRedol on 23.12. 2025 14:23
Found a used one which came off my Super Rocket, looks decent to me, private message me if this helps, although if you can wait alittle longer, check out Priory Magnetos who has them in stock, Andrew the owner is a member on here.

Thanks Billybream, appreciate your help. I'm going to see how the chain is once I've replaced the drive sprocket.

Regards
Title: Re: dynamo sprocket 11 tooth part No. 67-727
Post by: MRedol on 23.12. 2025 14:39

[/quote]
I stock these at Priory Magnetos, but you'll find that tight spots are inevitable with this setup. The culprit is more likely to be the drive sprocket which are nearly always eccentric.
[/quote]

Thanks for the info CheeserBeezer, maybe I'll see how the chain is once I've replaced the drive sprocket. Then I can decide whether to get the Dynamo sprocket replaced too.

Where on your website is the small 11 tooth dynamo sprocket part No. 67-727 listed?

Regards
Title: Re: dynamo sprocket 11 tooth part No. 67-727
Post by: MRedol on 03.01. 2026 16:22
I’ve fitted a new drive sprocket 27 tooth and new chain, but I’m still getting a tight spot. At the tightest point it’s approx 4mm play and loosest point it’s approx 9mm. Manual says it should be 6mm.

Does anyone have any thoughts on this please?

Any advice is much appreciated!
Title: Re: dynamo sprocket 11 tooth part No. 67-727
Post by: CheeserBeezer on 03.01. 2026 19:32

I stock these at Priory Magnetos, but you'll find that tight spots are inevitable with this setup. The culprit is more likely to be the drive sprocket which are nearly always eccentric.
[/quote]

Thanks for the info CheeserBeezer, maybe I'll see how the chain is once I've replaced the drive sprocket. Then I can decide whether to get the Dynamo sprocket replaced too.

Where on your website is the small 11 tooth dynamo sprocket part No. 67-727 listed?

Regards
[/quote]
https://sites.google.com/site/priorymagnetos/timing-chest
Title: Re: dynamo sprocket 11 tooth part No. 67-727
Post by: chaterlea25 on 04.01. 2026 16:51
Hi MRedol,
I'd say thats about the best you will get with a chain drive
Provided there is some slack at the tightest point and the chain cannot hit the screw boss at the loosest point it will be as OK as a chain drive can be on one of these

I am a convert to belt dynamo drives  ;)

John
Title: Re: dynamo sprocket 11 tooth part No. 67-727
Post by: MRedol on 05.01. 2026 08:22
Thanks John
I was a bit concerned about the screw boss. It’s already been worn by the old chain in previous life!

I was thinking about a belt drive conversion.

Any recommendations?

Regards
Title: Re: dynamo sprocket 11 tooth part No. 67-727
Post by: chaterlea25 on 05.01. 2026 13:08
Hi,
This one is £85 https://dynamoregulators.com/wide/drive-belt-kit.php

SRM's kit is £107

I don't know if there are others?

John
Title: Re: dynamo sprocket 11 tooth part No. 67-727
Post by: CheeserBeezer on 05.01. 2026 22:16
Hi,
This one is £85 https://dynamoregulators.com/wide/drive-belt-kit.php

SRM's kit is £107

I don't know if there are others?

John
These are no longer supplied by DVR. They are now supplied by Steve McFarlane, or myself, on Steve's behalf.
Title: Re: dynamo sprocket 11 tooth part No. 67-727
Post by: chaterlea25 on 06.01. 2026 13:03
Hi All,
Thanks for the update CB,
I just googled for answers in a bid to help
The DVR site looks to be still active??

John
Title: Re: dynamo sprocket 11 tooth part No. 67-727
Post by: CheeserBeezer on 06.01. 2026 23:26
Hi All,
Thanks for the update CB,
I just googled for answers in a bid to help
The DVR site looks to be still active??

John
My understanding is (and I may be wrong) that the business has changed hands. The new proprietor has moved the sales of the belt drive kit to Steve McFarlane (the originator of SRM) but has retained the voltage regulator side of the business. If I'm incorrect, I apologise. I'm just passing on what I've been told.