BTH Components Ltd.

Tel: 01908 550044

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BTH Components are UK distributors for the Alton generator range and carry stock offering our customers a next day delivery service. 

Our Range of Magnetos



A new model in the range a visually close replica of the Lucas flange mounted single magneto using the well proven electronics used in the rest of our magnetos.

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A new model in the range a visually close replica of the Lucas flange mounted twin magneto using the well proven electronics used in the rest of our magnetos.

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Platform mounted single cylinder magneto.

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Platform mounted twin cylinder magneto.  Similar in appearance to the single magneto shown but with two coils, leads, etc.

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A traditional Mag-Dyno retaining the original appearance of the Lucas MO1.  Also available for twin cylinder use.

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A Flange mounted, three bolt fixing single cylinder magneto.  Vincent Comet version also available - FM1C

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A Flange mounted, three bolt fixing twin cylinder magneto to fit most British parallel twins.

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A Flange mounted, three bolt fixing twin cylinder magneto for the Vincent V twin.

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Warranty Statement

For the best and most reliable results use a BT-H magneto for your ignition source.





Hello Peter,
I fitted one of your excellent Magnetos to my Venom in January of this year. I would have written to you earlier but as it rained for most of February I have only been able to take the Velo out for some serious road testing in the past couple of weeks.
First things first. The new Magneto was very straightforward to fit (if you discount the fiendish way Velocette attach their Magnetos to begin with, the need for doubly articulated fingers and a spanner which Salvador Dali would have been proud to own!). The interesting part was in finding somewhere to mount the HT connector. As I wanted the Venom to look as standard as possible I decided to locate it behind the battery box.  After making a small mounting bracket out of aluminium strip and relieving the back of the battery box  it mounted very neatly, out of sight on the rear battery strap.
Timing the ignition with the new Magneto was so easy that once completed (5 minutes) I was left with this strange feeling that I must have left something out or be doing something wrong - no cigarette papers, no requirement for three arms, or two sets of eyes, and no profane language - wow! How will it ever catch on?
The Venom started with the first kick and has done so every single time since!!! Hot or cold, one swing on the kick starter now brings it thudding into life. As Vinnie Jones (Lock, Stock and Two Smoking Barrels) might have said "It's been emotional". I can now actually don all of my bike gear BEFORE I start the bike.
Riding - The bike is now much smoother, pulls more strongly and revs much more freely than it did before. I still have some adjustments to make to the fuelling (I think the vastly improved ignition now allows other issues to show up more than they did previously) but it is a real treat to ride. I have spent a good deal of money on restoring my 1959 Venom but I can honestly say that the money I paid for the new Magneto was the best £600.00 I have spent on the bike (actually on any bike!). I would recommend it as a 'must have' purchase to anyone.
Thank you for your excellent service and wonderful product, absolutely fabulous.

Kindest regards

Dr Peter Spencer

United Kingdom

26th March 2014

Dear Peter,
What can I say but WOW. My Rapide has never sounded so good. The throttle response is amazing. The neighbour even put his head over the fence as he thought I had a new bike.
The unit was so easy to fit .
I canít wait to run the engine in now that I have confidence it wonít stall when hot.

Kind regards,

Cameron Harker
Norwood, SA 5067

"G'day Peter 

Many thanks, received the new mag and my 61 Bonneville is running better than ever. I'm really preaching the BTH over here in Oz. I was actually put on to you guys from a speedway friend of mine that uses your mags in his supercharge Vincent speedway bike. He has run them on all his bikes for years"

Jason Skewes

JKS Industrial Electrics P/L, Australia  


Hi Peter,

Hope you had a nice weekend. I finally got to ride my Gold Star I put one of your Mag-Dyno's on last year and it ran great!!! I've been trying to sort the ignition since about 2006 and finally threw up my hands and tossed the Alton and Boyer and went with your Mag-Dyno. And that seems to have sorted it! Many thanks!

I saw my friend Gus V this weekend and he is thrilled with his BT-H on his Vincent and can't wait to get his BT-H Mag-dyno mounted on his Gold Star. I'm telling everyone I know about the simplicity of your BT-H magnetos and mag-dynos!

Keep up the great work!

Barry Porter

USA  (4/11/2013)

Hi Peter,
I just wanted to drop you a line to let you know how incredibly pleased I am with performance and looks of my K2F style magneto. Not only was it a breeze to install and time, I have to say the engine has never run so well AND has the added bonus of fooling all my vintage bike loving buddies into thinking it was a genuine Lucas mag! Many thanks for a brilliant product...

Eric Holtje
23rd July 2013


Hi Peter,
Just a quick note to say I have started and tested the bike having fitted my new electromag!
It is a different bike now as it starts easily and pulls progressively through the rev range!
Good work!
Many Thanks
Philip Moss - Eire


Hi Peter
Arrived 5 mins ago - looks the business! Thanks!

Kerry Wilton - Dubai

BTH Components Ltd (BTH) Refund Policy:

BTH will refund the full purchase price of goods excluding carriage or shipping charges if the goods are returned in their original condition together with the proof of purchase within 7 days from receipt of delivery.

BTH are not liable for any damage to the product that results from improper installation, accident, abuse, misuse, natural disaster, abnormal mechanical or environmental conditions, or any unauthorized disassembly, repair, or modification.

BTH are not liable for refunds to any product on which the original identification information has been altered, obliterated or removed, has not been handled or packaged correctly, has been sold as second-hand or has been resold.

BTH is not liable for any packing and shipping costs to or from destinations in or outside of mainland Britain, and does not cover any costs associated with the customer determining the source of problems, removing, servicing or installing BTH products.

BTH will, at its option, either repair or replace any part of its products that prove defective by reason of improper workmanship or materials. Repaired parts or replacement products will be provided by BTH on an exchange basis, and will be either new or refurbished to be functionally equivalent to new.

BTH are not liable for customer error. We strongly recommend customers contact our customer helpline on 01908 550044 or email before purchases are made if they have any doubts of their requirements.

Company Profile.

BTH Components Ltd make new, self generating, magneto ignitions systems to provide easy starting and good performance.  They are suitable for  both road and competition use.  

Our aim is to give an efficient, friendly and personal service to all our customers.

N.B. We do not offer a repair service or supply any parts for BT-H magnetos made prior to 2002.

The BT-H name was purchased from Marconi in early 2002.
A historic note.  BTH, or more correctly BT-H using a hyphen are the initials of the original founders of the British Thomson-Houston company.   BTH magnetos were considered to be the magneto of choice in the classic era.

Please browse our pages for information about our self generating magnetos.   Products

Why risk using a tired old magneto when you can have a new one? - You can pay using our credit card facility. * Prices shown do not include V.A.T.*  

Warranty Statement.


Contact Information.

Telephone: 01908 550044 ( Office hours 0900 -1700 Monday - Friday.)


The best people use BT-H Magneto products.

Last Update: 30 July 2014

BTH Components Ltd.  Company number: 7700591.  Registered at: Companies House, Crown Way, Cardiff, CF14 3UZ.

Telephone: 01908 550044