The BSA A7-A10 Forum
Technical (Descriptive Topic Titles - Stay on Topic) => Lucas, Ignition, Charging, Electrical => Topic started by: Hyde61 on 15.04. 2012 17:20
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Hi i just join your forum hopeing somebody can help i have a bsa a7 shooting star in greenlaner form ie no electrics just a lucas kf2 magneto i bought the bike about three years ago not seeing running anyway to get to the problem afer sorting the engine out.
how do i check the mag have tryed kicking it over with the plug on the side of the engine nothing its had new pick-ups plugs ,
also has anybody got a pic of how the points should look like as i dont now what the preivous own did ie is there a washer missing
hope somebody can help
thanks for reading
ps its got atd on it
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I would advise removing the points and cleaning the faces. In principle the moving arm is connected to the base plate, whilst the fixed point is insulated from the base plate but connected to the magneto low tension circuit via the central fixing screw. So, with the points removed, there should be no electrical continuity between the fixed point and the baseplate whilst the points are open. Do you have the early solid brass points or the later pressed metal (low inertia) points?
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The later ones break at the baseplate. Get some proper brass ones if you can.
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Hyde,
Welcome to the forum. I guess the first thing I should do is thank you for teaching me a new bit of slang, "greenlaner", which I assume means offroad on trails, maybe through the woods. (You know, us Americans need everythng explained to us.)
Below are two pictures of points, both with brass bases (left-click on them to enlarge). The first one is courtesy of our administrator (goes by the nickname "e") . The second is from my magneto, where you can see the addition of an "EasyCap" from Brightspark Magnetos. They have quite a bit of good magneto information on their site at http://www.brightsparkmagnetos.com/ . In the picture of my points, you will also see a lockwasher under the points fixing nut. Not sure why "e" doesn't have this. Maybe his is correct and mine is not. I don't know if this is the washer your referred to.
Lack of spark can be due to several different things: bad brushes, bad plug wire, bad caps, bad plugs, bad capacitor (inside mag), bad mag coil, demagnetized magneto (probablay not), dirty slipring, bad slipring, bad points (or points adjustment), and more. When you have the plugs out, cleaning the slipring is a good idea. It also gives you a look at the brushes. Just remove the brush holders and kick over the bike while using your finger behind a clean rag. Sorry if you already know all this, but I couldn't reckon your skills from your post.
Here is a link to service and repair tips for Lucas magnetos:
http://archives.jampot.dk/Technical/Electric/Technical_tips/Magneto_Tips_by_Mark_Seibert.pdf
Richard L.
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Thanks to you all for the imput will try all of them just thought i would put a pic of the points in question ,
i am in ireland so if anybody knows of were i can get the brass plate type from that would be great
thanks again
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On the steel points you've got there Hyde the spring point is live and the fixed one earth. So maybe worth being quite sure the spring and its retaining screw at the tail can't in any circs touch the lobes on the cam ring? Looks OK, if close, in the pic, but I'd check on the other lobe and also at rpm, in case there's anything funny going on there.
If anyone has any NOS brass assemblies, I guess we'll all be forming an orderly or disorderly line! 2nd hand ones come up, but if you find one you may well find it needs a new pivot for the moving point to get it how it should be in terms of clean making and breaking. Do-able, but a fiddle. Best of Luck.
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Hi Hyde, the steel plate should work as well as the brass ones and a further consideration is you need a different centre bolt for the brass one.
in your photo the spring does look a bit close to the camring but that might just be the photo, but check it out as suggested by Groily
Hi guys I have a spare brass plate set *smiley4* - may have to sell if Osborne continues his assault on the elderly *fight* *evil* *evil*
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I have been reminded to mention that, while cleaning the slipring, the rag in front of your finger should be thick enough to keep you from getting shocked. Otherwise, maybe a friend can hold down the kill switch.
Shocking!
Richard L.
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maybe a friend can hold down the kill switch.
better still get your friend to put his finger on the cloth ( you could run out of friends though)
seriously though next time your in a coffee shop or Starbucks avail yourself of a good few of those wooden stirrers, glue a bit of felt onto the end of them and leave to set.
You will then have a stock of slip-ring cleaners (you will need to shorten some for the engine side)
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Thanks again guys going to try again tommorow will keep you posted fingers crossed mite get the wife to stick her fingers on the slipring *smile*
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(you will need to shorten some for the engine side)
Good one!
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Bill,
Sorry, can't tell if you're joking about "engine side". Do you mean the lower brush-holder hole? If so, and if you are serious, why?
Richard L.
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Hi Richard
Well spotted, I got that one wrong it is the other side (rear) that is a bit awkward, the sticks are quite long and I found snapping a bit off made it easier to poke down the contact hole.
sorry about that, probably should write mails in the shed sitting beside the bike.
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Hi, Hyde 61,
Welcome to the forum from a fellow Irish, BSA owner, there are a few of us here *smile*
Where are you located?, I live near Cork City
I work on Classic bike repairs/resto's and could check the mag over for you if you are not at the opposite end of the Country
Best Regards
John O R
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HI I AM NEAR WEXFORD JUST 3 MILES FROM KILMORE QUAY
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Hi John,
Off topic but I just recently found one of my ancestors was "relocated" from Cork to Australia.
Back to points, I recently repaired an AJS magy which has the steel point plate.
I don't know the chain of events but one leaf of the spring was broken, the points bent and the fibre heel block was broken through the spindle hole.
No choice but to replace with the same. Poor quality as the radial slot had to be filed to allow the securing screw to go home.
Trev.
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*clap*Nice one B-Bill,made me laugh better still get your friend to put his finger on the cloth ( you could run out of friends though)
Kind of what I had in mind ,but you got there first, until-> You will then have a stock of slip-ring cleaners (you will need to shorten some for the engine side)
??? sounds like something I'd say on a 'good' day?? *doh*=lost cred .
Jeez, yeeaah,but not quite how it's done 'down-under', must be some U-beaut Northern hemisphere trick ,or you're using mirrors?! But good thing Richard L. 's on the ball, blew all theories away++brownie points *beer*wink2
RL, saved those links- look interesting
Hey Hydeyho, good luck with the missus-I'm sure she's too smart, unlike me 13yo I got scammed into poking finger into BIG old Tractor maggie (Twin City MM if that means anything ta anyone)
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HI ALL
HAD A BIT OF TROUBLE LASTNIGHT THOUGHT I WOULD GIVE THE POINTS A CLEAN NOT A GOOD MOVE WENT OFF LIKE A CLOCKSPRING PLEASE SEE PICS
FEEL LIKE FOREST GUMP JUST CANT SEEM TO GET THEM RIGHT I NOW DONT SAY IT
HELP?
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You need to remove the base plate of the points from the mag before starting to reassemble. Put the centre screw back into the centre of the points but don't start to screw it in, just jiggle it about firmly from side to side to release the base plate off its taper. I'll put some pics on later or talk you through it.
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Pictures of reassembly now on the Tech Tips page of my website. Hope this helps.www.priorymagnetos.co.uk (http://www.priorymagnetos.co.uk)
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See that round hole on the left? That
is where they break because there isn't much material left around it.
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Hi All,
REMEMBER *ex* *ex* that thes points plates can be assembled in two ways to suit opposite rotation ???? ????
beezermacc's page has it correct for the A10 application
HTH
John O R
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HI GUYS
I WANT TO THANK YOU ALL FOR THE COMMENTS AND TAKING THE TIME TO HELP ME WITH MY PROBLEM ,WANT TO GIVE A BIG THANK YOU TO BEEZERMAC FOR THE STEP BY STEP PHOTOS ON HIS WEBSITE FOR PUTTING THE POINT BACK TOGETHER THE RIGHT WAY HIS WEBSITE IS BRILLIANT
Priory Magnetos Ltd.
AND HIS PRICES ARE VERY GOOD
THANKS AGAIN
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Hi All,
REMEMBER *ex* *ex* that thes points plates can be assembled in two ways to suit opposite rotation ???? ????
beezermacc's page has it correct for the A10 application
HTH
John O R
Hyde 61 - Thanks for the kind remarks.
Chaterlea 25 - I think you'll find that the hardened contact button is on one side of the fixed plate only. There is only a plain rivet on the other side. If you want to reverse the rotation (for a Royal Enfield for example) you can flick the moving arm over but you need the correct base plate with a hardened point on the left.
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HI GUYS
THOUGHT I WOULD JUST LET YOU ALL KNOW I HAVE SPARKS FROM THE PLUGS FEEL LIKE A NEW FATHER AT HIS FIRST CHILDS BIRTH WILL POST A PICOF THE BIKE WHEN IT ALL TOGETHER .
THANKS AGAIN TO EVERYBODY FOR THERE TIME
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Sparks are good..... I like sparks!
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Hi beezermacc,
I live and learn *ex*
I never liked those points setup , I have slung them as far away as I can and fitted the brass backplate type
Better still I have a BTH (original) on my SR
Cheers
John O R