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k2f's

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k2f's

Posted by neil_waterton at July 07. 2017

Not trying to be a numpty here but are all  K2f's the same or are they model specific? Would a K2F off a 1963 A10 Beeza fit a 1968 Atlas without modification? Maybe the drive end is different by keyway or cone fit, cam different to each model etc . If my Magneto isn't showing a spark at the plug, rather than sending it off for a full re-fit at maybe 3-400 pounds i could buy a refurbished one for same money. I await a lesson and bow to those with more knowledge(sic)

Cheers all.  Neil

Re: k2f's

Posted by robert_tuck at July 07. 2017

Could be something really simple like a worn earthing brush,these can be a bit hidden.

Re: k2f's

Posted by howard_robinson at July 07. 2017

Hiyah Neil,  Your '68 Atlas would not normally have a magneto fitted. If it has however it should be a counter-clockwise rotation ( see arrow on mag plate identifier )  Type K2F ( or K2FC / K2FR ).  Normally on a Norton the end cap is a screw on type with a cut-out brush in the centre of the end-cap connected to a cut-out button on the handlebar.  A '63 BSA A10 would also use a similar K2F ccw type but with the small round end-cap with a press in cut-out on the end-cap.  The taper on the armature is the same as is the size and thread form at the armature end.  Some of the Rocket types did have a manual advance /retard mechanism cable operated into the cam ring portion at the points side of the mag.  This would require a fixed drive sprocket or a method of jamming the cam ring if you retained the Norton auto advance unit.   Many things are possible with the K2F mags.  Cheers and good luck, Howard

Re: k2f's

Posted by les_howard at July 07. 2017

There are several variations but most can be substituted apart from the Royal Enfield Twins variant which runs clockwise viewed from the drive end. The other major variation is that the shaft is sometimes designed for the fitment of an auto advance timing unit but others are for fixed pinions or cogs and have manual advance and retard on the points end.

I would do an electrical test first.

1) Test the primary coils resistance....see my K2F post I stuck on yesterday. http://www.nortonownersclub.org/noc-chat/technical7-electrical/632302115

2) Test the resistance of the secondary coil by measuring at the HT lead (make sure this is a copper one) and the mags body. You should have a reading of about 5K Ohms.

Servicing a magneto (bearings and seals etc) is quite easy and will cost around 40 quid tops. At worst you will need the armature rewound with new capacitor....this will be around 150 quid.

So I recommend doing the resistance test first and post the results here. It could be simply that the points or earthing brush is dirty.

Do the preliminary tests ....you might save 300 quid or more.Wink

 

Les

Re: k2f's

Posted by anna jeannette Dixon at July 07. 2017

Hello I have all manuals and maintenance  manuals on of K2f And K2FC K2 FR  K2f- VC  And The Atlas used the K2FC ANTI-CLOCKWISE  there are two earthing brushes  one behind the points body and the other at the magneto end brush  next to the mounting point  and all magnetos  are dated  to the machine has stamped on the plate on the mounting point   and more information need just ask  yours  Anna j

Re: k2f's

Posted by neil_waterton at July 08. 2017

On closer inspection, the mag has the counter-clockwise arrow on the plate, but the end cap  (the points end) has two dome-headed nuts at about two o'clock and 8 o'clock hold the cap in place. Also the manual advance/retard has been unconnected with a bolt and nut stopping up the hole for the 'mushroom type plunger and cable entry. Will try and I.D. the serial number, but looks a cow to get the end cap off to check points etc. The 8 o'clock nut seems to be right behind the primary chaincase back plate. Looks like all primary side off first then the mag off. Any sugestions as to why this set up was adopted.? Maybe just a cheap any-old-mag will do to get it going? Any way no spark so will dig further.

thanks all. Neil

Re: k2f's

Posted by neil_waterton at July 08. 2017

Previously howard_robinson wrote:

Please delete this spurious input Mr Webmaster....Howard

?????? I do hope you dont think I am wasting peoples time, and if my questions are a bit too menial for you I am sorry about it. Going by the timing of your second comment it seems you think I am posting 'spurious' comments. If this comment is directed at someone else, kindly address it as such. Thank you.

p.s. your first comment was most helpful that's why I am a bit perplexed.   Neil

Re: k2f's

Posted by howard_robinson at July 08. 2017

Nothing to do with your questions Neil.  For some reason my response got repeated so I went to edit mode and deleted the text but it would not delete the entry...

Regarding the end cap on your magneto - it's obviously not the screw-on type preferred by Norton.  Sounds like an early BSA type.  There will be a year of manufacture on the mag plate.  There will be a code with the month and year. (so  0552 would be May 1952 etc) .  Don't forget that the spark plug gaps for a mag shold be adjusted to about 15 thou.  New ones are usually set to 25 thou - for car coil ignition systems.   Your magneto points need to be 12 thou.  When you get the end-cap off you may be able to fit some studs and then fit some special double hex nuts like many electrical items have these days.  Often the connection from the armature to the slip ring goes high resistance and is easily rectified.  Cheers, Howard

Re: k2f's

Posted by David Cooper at July 09. 2017

I ground a spanner sides well down and keep it for that bottom nut. It is just possible to access from below one twelfth of a turn at a time... turning the nut a bit and turning the spanner over. Luckily that stud and nut are stainless on mine and if clean it spins off after it is slack. There are alleged to be long extended  replacement bolts from BSA  but I don't know how or if they fit.

Re: k2f's

Posted by les_howard at July 09. 2017

Much easier to use a long BSA type nut...makes mag adjustment a doddle!

Les

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Re: k2f's

Posted by Fritz Wettstein at July 10. 2017

Previously les_howard wrote:

Much easier to use a long BSA type nut...makes mag adjustment a doddle!

Les

Where did you get this? Part-No?

Fritz

Re: k2f's

Posted by neil_waterton at July 10. 2017

Previously Fritz Wettstein wrote:

Previously les_howard wrote:

Much easier to use a long BSA type nut...makes mag adjustment a doddle!

Les

Where did you get this? Part-No?

Fritz

Ebay uk has several from £12 to £15, just type in 'BSA k2f long nut.' There are 1 or 2 period parts and a few new pattern ones in stainless. CPC engineering in Redruth, Cornwall  has them listed.  p/no. 67-1259

Neil

Re: k2f's

Posted by Gordon Johnston at July 10. 2017

Some of the new pattern BSA long nuts have a thick shank which makes them a pain. The original BSA ones have a slimmer shank and they go straight on. As mentioned, it does make life so much easier. Considering the BSA and Norton twins had the same designer, he could have specified long nuts for both types...

Re: k2f's

Posted by les_howard at July 10. 2017

Hi fritz...as others have said there are several sources but the photo is the one from this seller:

http://www.ebay.co.uk/itm/Long-Magneto-Bolt-Nut-for-BSA-A7-A10-Triumph-Pre-Unit-67-1259-/311520538385?epid=684258145&hash=item4888122f11:g:JF4AAOSwpLNX9OUd

Les

Re: k2f's

Posted by Fritz Wettstein at July 10. 2017
Previously les_howard wrote:

Hi fritz...as others have said there are several sources but the photo is the one from this seller:

http://www.ebay.co.uk/itm/Long-Magneto-Bolt-Nut-for-BSA-A7-A10-Triumph-Pre-Unit-67-1259-/311520538385?epid=684258145&hash=item4888122f11:g:JF4AAOSwpLNX9OUd

Les

Thank you Les. I've ordered one, just in case I'll have to go at it sometimes. Fritz

Re: k2f's

Posted by neil_waterton at July 20. 2017

Just took the mag off for a refurb. I suppose because the bike is a '68 it doesn't have the almost impossible nut under the mag. The third nut is in the timing chest behind and slightly below the auto a/r unit and a shanked bolt goes right through the mag body and the timing chest back.

All the internals are very manky, the slip ring and the earthing ring were almost same colour as the varnish on the windings, so a good clean up is in order. will then put new points in and test it best i can. Will probably be asking all sorts of q's soon.about it. Thanks for contributions so far.

Neil

Re: k2f's

Posted by kevin_wood at July 20. 2017

Make sure you disconnect the stop switch to the end of points before anything else.

 

i had pic ups which were broken, but not obvious last year. New ones and a clean of slip ring had her sparking correctly again.

 

All worth a try. No suppressed plug caps either with a mag.

 

make sure points are doing what they should do and there isn't a fag paper debris left behind to insulate the gap! I have never done that before!

 

Kevin

 

Re: k2f's

Posted by neil_waterton at Friday 12:32

Previously kevin_wood wrote:

Make sure you disconnect the stop switch to the end of points before anything else.

 

i had pic ups which were broken, but not obvious last year. New ones and a clean of slip ring had her sparking correctly again.

 

All worth a try. No suppressed plug caps either with a mag.

 

make sure points are doing what they should do and there isn't a fag paper debris left behind to insulate the gap! I have never done that before!

 

Kevin

Thanks Kevin. well worthy to note these things. new pick-ups are on the way and new points. On dismantling the points plate i noticed 2 fibre washers not seeming to do much, one was under the plastic 'number 8' shaped plastic moulding and one seemed to be keeping the bakolite 'heel insulated from the base plate. Metal ones (3)  and a shakeproof one on the screw . It all seems a bit of a mess, do you know of a proper 'exploded view of components that make up the points and the base plate, and where the metal and fibre washers all live? Have trawled the net to no avail at the moment. Thanks, and thanks to all who read and take an interest. BTW the body of the mag (totally stripped) went into my new ultrasonic cleaning bath and came out like  'factory new', well pleased. Will be making this service available to any members living near Brackley when I move in September. Prices will cover costs only, as I am retired (and I do know what cost and profit means.)

Neil

Re: k2f's

Posted by les_howard at Friday 14:11

Not sure of what bits you mean but here is a link to everypart of the mag....pleased you are having a go....don't hesitate to ask questions:

http://brightsparkmagnetos.com/library/Parts%20lists/Lucas%20motor%20cycle%20parts%201936-57/G09-23%20Magnetos%20and%20ATDs.pdf

The download starts a bit slow......Les

Re: k2f's

Posted by neil_waterton at Friday 16:13

There is no exploded view of the component parts to the points base plate and mounted points. The problem is if I go and put a fibre washer where one shouldn't be, we will end up with zero sparks, and keep pulling it apart and rebuilding the plate instead of building it to an exploded view. sounds a bit anal, but the only way I can see around it is to buy the complete unit, points and base plate as they are supplied together. Classicmotorcyclespares (part of vintagemotorcycles.co.uk) sell one for about £30.,however they are out of stock at the mo. Until I can get a 'took-apart' look at a diagram of the thing i will just keep cleaning,dismantling and boxing bits up. (ready for house move!)

Thanks again.  Neil

Re: k2f's

Posted by John Shorter at Friday 17:38

Or, you could forget about points, field coils, brushes etc, and got a Thorspark unit!

Re: k2f's

Posted by les_howard at Friday 17:42

The K2F contact breaker plate is very simple...The photos are from "Brightsparks" web site....all that is different is the green circuit board shown has replaced the insulating plate that you will have. Note that there are two types of CB plate the newer ones have the open steel moving contact arm whereas the older one uses a brass holder for the points set. The electrical test is to make sure that when the points are open there is no short to the main part of the CB plate from the FIXED contact....but the fixed contact contacts the primary via the long centre bolt that holds the whole CB plate to the armature and allows to rotate with it....Les

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Re: k2f's

Posted by John Sunderland at Friday 20:06

Previously John Shorter wrote:

Or, you could forget about points, field coils, brushes etc, and got a Thorspark unit!


I'll second that. I fitted a Thorspark to my Slimeline 99 the other week after trying and generally failing to get my bike to run properly due to an eccentric cam ring. What a difference. Starts first kick, no more faffing about with points etc. Fairly easy to install and set up.

Re: k2f's

Posted by neil_waterton at Friday 21:17

Previously John Sunderland wrote:

Previously John Shorter wrote:

Or, you could forget about points, field coils, brushes etc, and got a Thorspark unit!


I'll second that. I fitted a Thorspark to my Slimeline 99 the other week after trying and generally failing to get my bike to run properly due to an eccentric cam ring. What a difference. Starts first kick, no more faffing about with points etc. Fairly easy to install and set up.

Thanks John, As I have said in previous subject posts, I am no purist, so a recommend is much better than any good advertising blurb. Your comment (and others) and a bit of non-partisan research has sold me on the Thorspark. I've told the Mrs that a mag refurb or worse, a rebuild could be upward of £300 so this adds up to very good sense to invest in. Just got to get the core mechanicals checked first, then concentrate on getting her running. The Atlas that is, not the Mrs.

Many thanks.

Still looking for any commments re: my Ultrasonic cleaning bath. Its a big one (30 litre) so will take crankcase halves, timing chests outers, heads, oil tanks etc. Any thoughts , guys and girls ??

Re: k2f's

Posted by les_howard at Saturday 09:12

Hi Neil...Looks like you won't want the original CB plate then...so any chance of letting me have it?....I'm building another K2F from old bits...no prob if you do want it...it's just that you might be throwing it away?...Frown....Les

Re: k2f's

Posted by neil_waterton at Saturday 09:55

Previously les_howard wrote:

Hi Neil...Looks like you won't want the original CB plate then...so any chance of letting me have it?....I'm building another K2F from old bits...no prob if you do want it...it's just that you might be throwing it away?...Frown....Les

Hi Les, your very welcomed to anything not needed with the Thorspark install. I am a bit magpie-ish, and never throw anything away especially old stuff or related to 'old'.  I specialised in CX500 Hondas for a while (1978 to '83 models) and rebuilt lots of engines and three  complete bikes. All gone now but still have a dozen storage boxes full of spares for that model. When we move I will have to do a major sort out. !! PM me or get in touch through here for contact/address swap etc. Will be probably a month before I get round to sending the bits to you so hope your not in a hurry. Best for now. Neil

Re: k2f's

Posted by les_howard at Saturday 13:57

Thanks Neil .....I'm the same though, very reluctant to throw anything away. I even keep all the rusty nuts and bolts from any refurb...not that I'm ever likely to use them again...it's just the "sentimental value"...how daft. Don't worry if you do want to keep it, I was just getting in quick in case you binned it and that would have been a waste. Some people can throw things away without a second of thought. You just need to go to the local re-cycling centre to see what people throw away. I once got a petrol mower which was nearly new, someone had thrown it out as the engine must have been revving away simply because the small governor spring had been knocked off the carb! Unfortunately I've moved house and my centre does not allow anything to be taken out once dumped....Perhaps it's a good thing, I'd be up there everyday bringing back loads of stuff...Sorry for sort of hijacking your post but it's back on top again....Les

Neil's last message says:

Still looking for any commments re: my Ultrasonic cleaning bath. Its a big one (30 litre) so will take crankcase halves, timing chests outers, heads, oil tanks etc. Any thoughts , guys and girls ??

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