Where to find 3 1/2 Ignition Coil Formers ?

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AK99
Posts: 22
Joined: 10 Jun 2025 15:00
Location: Dublin, Ireland

Where to find 3 1/2 Ignition Coil Formers ?

Post by AK99 »

Good folk of the Riders Forum...

I need to source a new former for the ignition coil on the Strada. A friend of mine has dismantled the unit for rewiring, and the original 47 year old former has disintegrated.

I had a look across the forum using the search function there, but haven't been able to find info on how to go about sourcing one.

Qn: Is there anybody who can currently 3D print and supply one of these - or indeed are there any alternative / aftermarket coils off scooters or the like which could be stripped down to get a workable substitute ?

Any and all help appreciated as ever,

Thanks, Alan
A BigVee, a WeeVee, and a triple.
3potjohn
Posts: 1452
Joined: 02 Jun 2007 13:58
Location: Devon

Re: Where to find 3 1/2 Ignition Coil Formers ?

Post by 3potjohn »

I got a bobbin from Paul Compton a couple of years ago- he had some made. Maybe there are some left?
AK99
Posts: 22
Joined: 10 Jun 2025 15:00
Location: Dublin, Ireland

Re: Where to find 3 1/2 Ignition Coil Formers ?

Post by AK99 »

Is Paul a member on here by any chance, or would someone have contact info they might share ?

Currently looking at the possibility of sourcing a Vespa lighting coil to strip and use the former from.
A BigVee, a WeeVee, and a triple.
Morini Jen
Posts: 374
Joined: 12 Jun 2022 18:49
Location: Warwickshire U.K.

Re: Where to find 3 1/2 Ignition Coil Formers ?

Post by Morini Jen »

Hi Alan.

Paul is the Morini Riders Club Technical Guru.

Contact details are in the back of A Tutto Gas.

Jenny.
AK99
Posts: 22
Joined: 10 Jun 2025 15:00
Location: Dublin, Ireland

Re: Where to find 3 1/2 Ignition Coil Formers ?

Post by AK99 »

Thanks Jenny - appreciated.
A BigVee, a WeeVee, and a triple.
RobinSF1
Posts: 85
Joined: 29 Jun 2020 06:05
Location: Merthyr Tydfil Wales

Re: Where to find 3 1/2 Ignition Coil Formers ?

Post by RobinSF1 »

I had an ignition coil rewound onto a new bobbin by BB bikeshop, the invoice included the bobbin £7 (this was last year). Give Roger a call.

BB Bikeshop
Unit 20 Chiminage
Marlborough
SN8 1BW
UK
01672 512240
07733322574
www.bbbikeshop.co.uk
info@bbbikeshop.co.uk
AK99
Posts: 22
Joined: 10 Jun 2025 15:00
Location: Dublin, Ireland

Re: Where to find 3 1/2 Ignition Coil Formers ?

Post by AK99 »

Thanks Robin.

Had already spoken to Roger at BB Bikeshop before I picked up on your post - really helpful chap.

Turns out the plot has thickened a bit..

I forwarded Roger pictures of the ignition coil and former - and he came back to me and advised that the OEM spec bobbins he has are a different size. We then to and fro'd further and have since come to the conclusion that the stator coil itself is definitely not an original Morini / Ducati one - but more likely perhaps something originally off a Lambretta / Vespa.

I now need to try to identify the stator and / or the correct coil/bobbin dimensions required to fit that.

Old bikes - eh :)
A BigVee, a WeeVee, and a triple.
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George 350
Posts: 567
Joined: 16 Jun 2007 09:43
Location: Northampton

Re: Where to find 3 1/2 Ignition Coil Formers ?

Post by George 350 »

It might be a Morini one that you have. It might depend upon what stator is fitted.
As the alternator power output went up, the amount of laminations within the stator increased.
What I don't know, is whether the increased number of laminations for the alternator also carried through for the ignition coil or not.
Hopefully someone with greater knowledge of this will be able to answer this.
Regards George
George
350 Sport 1978, 350 Strada 1978
650 Norton 1967, 650 Kawasaki 1977 and 650 Enfield 2019
norbert
Posts: 926
Joined: 15 May 2007 15:15
Location: Lübeck/Germany

Re: Where to find 3 1/2 Ignition Coil Formers ?

Post by norbert »

As far as I know normaly the ignition coil stayed the same. That means a reduced packet of laminación for the ignition coil (normal size as on the former alternators) compared to the rest of light coils (I'm even not sure if all of them have thicker lamination, there are two types).
But I've also heard talking of a type of alternator with ticket laminación for all coils. Have nevera seen one of this.
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