The BSA A7-A10 Forum

Technical => Lucas, Electrical, Ignition => Topic started by: michael snellin on 17.10. 2013 13:08

Title: magneto????k2f
Post by: michael snellin on 17.10. 2013 13:08
Hi, just want to know does the diven end of the mag??? turn clockwise when the rest of the timing gear runs ie;  the camshaft, and  the crankshaft in the direction of clockwise?? otherwise they dont mesh with the av/rt unit, a little baffling?????? somewhere i know i have it wrong.
Title: Re: magneto????k2f
Post by: a10gf on 17.10. 2013 13:26
About the mag itself, see http://www.a7a10.net/forum/index.php?topic=7620.msg53565#msg53565
Title: Re: magneto????k2f
Post by: bsa-bill on 17.10. 2013 18:20
I think what your after is - crankshaft turns clockwise which turns the idler pinion anticlockwise which turns the camshaft clockwise which then turns the A/R unit (and magneto) anticlocwise
so it is the idler gear that keeps both the crank and camshaft turning the same way
I'm not so sure what you mean by
Quote
otherwise they dont mesh with the av/rt unit
is this to do with timing the magneto?, if so I'm sure we can help further , just need to know what stage your at with fitting the magneto
Title: Re: magneto????k2f
Post by: wilko on 17.10. 2013 23:19
This is what confuses most people when looking for the correct rotation tacho drive!
Title: Re: magneto????k2f
Post by: KenF on 19.10. 2013 06:38
Hi, just want to know does the diven end of the mag??? turn clockwise when the rest of the timing gear runs ie;  the camshaft, and  the crankshaft in the direction of clockwise?? ...

Some time ago, we put a quiz up on our web site about which way a magneto turns. See how well you can do!

http://brightsparkmagnetos.com/faqs/FAQs%20about%20magnetos%20generally/Why%20are%20some%20magnetos%20driven%20clockwise%20and%20others%20anti-clockwise.htm (http://brightsparkmagnetos.com/faqs/FAQs%20about%20magnetos%20generally/Why%20are%20some%20magnetos%20driven%20clockwise%20and%20others%20anti-clockwise.htm)

Ken.
Title: Re: magneto????k2f
Post by: duTch on 01.03. 2014 23:06
 *conf*

 Still ends up same rotation, but what engine is that???
Title: Re: magneto????k2f
Post by: beezermacc on 04.03. 2014 00:37
Hello Michael. The magneto you have there is quite unusual and I would suspect from a Royal Enfield or even a Vincent. How do I know?.. Because the manual advance/ retard cable housing is on the right hand side of the points when looking directly at the points. I would expect all K2F's to have a 'slack cable advance' arrangement i.e the magneto is in the fully advanced position when the adv/ret cable is in the relaxed position on the handlebar lever. The magneto in your picture, if it is unmolested, is designed to run clockwise drive / anticlockwise points, so is unsuitable for A10. The majority of magnetos passing through my workshop have got mismatched components, but when the components have been swapped between magnetos of different rotation all sorts of head scratching can follow. It would be possible to use your magneto provided you have the correct cam ring and points but then you will have a 'tight wire advance' arrangement. if you send me a close up photo of the points and cam ring in situ I can let you know what you've got and how to proceed. www.priorymagnetos.co.uk   www.priorymagnetos.co.uk (http://www.priorymagnetos.co.uk)
Title: Re: magneto????k2f
Post by: chaterlea25 on 05.03. 2014 21:53
HI All,
Remember that the A10 needs a chamfered body as well !!!!

HTH
John
Title: Re: magneto????k2f
Post by: trevinoz on 06.03. 2014 20:13
Not always, John.
I had a competition magneto on the RGS for years and it fitted with no clearance issues.
Getting the pick-ups out was another story, though!

Trev.
Title: Re: magneto????k2f
Post by: duTch on 07.03. 2014 02:57


 Out of curiousity, never worried about this info before, but which bit needs chamfer..?
 Also, what model K2fs are normally fitted to A10/7....?
 
 I have a  42174 B with auto, and it fits fine- as per photos, but I have no idea what it's originally fitted to, even the Lucas book doesn't say, but it does mention it at least..?
Title: Re: magneto????k2f
Post by: chaterlea25 on 07.03. 2014 19:22
HI All,
Pictures of the chamfered body in this post

http://www.a7a10.net/forum/index.php?topic=1385.msg9873#msg9873

HTH
John
Title: Re: magneto????k2f
Post by: trevinoz on 08.03. 2014 21:37
Hi Dutch,
                    Your magneto was originally fitted to a 1950 A7/A10.
Or should I say the tag was? 

Trev.
Title: Re: magneto????k2f
Post by: duTch on 09.03. 2014 04:47
Thanks Trev, I've had it since late seventies, but anything could've been done to it before that...nice to know though, that at least some of it likely started out on an 'A'...... *good3*
 
 it's funny that when I started on mine I had no intention of restoring, mainly 'cos of lack of info/parts,(just wanted to keep it all BSA) but as things go there's more 'legitimate' parts than I expected....the path of least resistance..... *whistle*

cheers
Title: Re: magneto????k2f
Post by: beezermacc on 10.03. 2014 09:19
Hi Dutch,
                    Your magneto was originally fitted to a 1950 A7/A10.
Or should I say the tag was? 

Trev.
The tag looks pretty original with the original rivets so maybe the whole body was A7/ A10 but the cam ring housing has certainly been flown in from elsewhere!
Title: Re: magneto????k2f
Post by: duTch on 10.03. 2014 14:49

 
Quote
maybe the whole body was A7/ A10 but the cam ring housing has certainly been flown in from elsewhere!

 eeeerrrgh *pull hair out* *beer*...ok thanks Beezermacc, I've seen piccies of bikes with that cover, but not taken lots of notice, I don't care so much- just curious, cheers
Title: Re: magneto????k2f
Post by: a10gf on 10.03. 2014 15:02
^^^ I've got the 'door bell' cutout cover, on a manual cam advance housing.
Title: Re: magneto????k2f
Post by: trevinoz on 10.03. 2014 20:50
Andrew,
                      The end cover on Dutch's magneto is probably the one which belongs to it, though modified for a cut-out wire.
The A7/A10 used this set-up until 1951 when the Bakelite cover incorporating the cut-out contact was brought into use.

Trev.
Title: Re: magneto????k2f
Post by: duTch on 10.03. 2014 23:59

 Yes I still have the original spring loaded button- I did the mod myself .
 It's a bit tricky getting at the button in a hurry while still in gear....!!!

 To do the mod, I used a regular spare pickup brush and spring in a short length of thin copper pipe with brass washer soldered on for a internal flange,sheathed with plastic tube and fibre washers each end for insulation, and brass washer with Stainless metal thread  set-screw.
 Must've had to drill out the spring seat from the body though..!!
Title: Re: magneto????k2f
Post by: beezermacc on 12.03. 2014 23:22
Andrew,
                      The end cover on Dutch's magneto is probably the one which belongs to it, though modified for a cut-out wire.
The A7/A10 used this set-up until 1951 when the Bakelite cover incorporating the cut-out contact was brought into use.

Trev.
You're absolutely right (Trev), it is quite unusual to come across a magneto which has not had its various bits and pieces swapped about. A Vincent or Enfield owner would be glad of the cam ring housing though because they are as rare as hens' teeth. If he offers a swap he'll want cash as well!