Author Topic: Magneto problem?  (Read 2683 times)

Offline renos-a10

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Magneto problem?
« on: 28.03. 2011 07:39 »
Goodmorning all

I believe that i have problem with my magneto.So i need you light.
I make restore my BSA a10 from the begining ( engine - frame etc.)
I start the engine and all was find.I take a ride and i stop for relax.
The engine didn't start. I check the fuel and all was ok.
I charge the spark and that's it. But this problem is come again and again.
I believe that problem ..... magneto.What you believe?

Thanks in advance
1954 BSA A10 Plunger
Cyprus

Offline MG

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Re: Magneto problem?
« Reply #1 on: 28.03. 2011 08:48 »
Hi renos!

Sounds like a faulty condenser. Does it work again once the mag has cooled down?

The condenser is located inside the armature, so that has to come apart. Once you are at it, I would also have the armature rewound. Not cheap, but when done properly, it will last for ages.

Cheers, Markus
1955 A7 Shooting Star
1956 A10 Golden Flash
1961 Matchless G12 CSR

www.histo-tech.at - Restoration, Repairs, Racing

Austria

Offline renos-a10

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Re: Magneto problem?
« Reply #2 on: 28.03. 2011 09:06 »
yes . it work again when cooled.
You believe that my mg need rebuild?
thanks
1954 BSA A10 Plunger
Cyprus

Offline Pete Gray

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Re: Magneto problem?
« Reply #3 on: 28.03. 2011 09:36 »
I had what sounds to be a similar problem on mine soon after it had been rebuilt.
It had run really well for a few miles then suddenly became erratic and wouldn't keep running.
I took the Mag back to the repairer (FTW in Sheffield) and on test they found that the head of the points securing screw was touching, or very close, to the cam ring causing a short. A replacement screw and the problem was solved.

Pete

1961 Swinging arm A7
2000 BMW R1100R

Online lawnmowerman

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Re: Magneto problem?
« Reply #4 on: 28.03. 2011 09:39 »
The mag is the heart of the engine and causes all sorts of obscure problems when playing up. It is not cheap to get a recon and rewind but the best money I have ever spent on my bike.
Make sure that you go to a reputable mag rebuilder.

Jim
1959 A10 SR
1938 Wolseley 14/60
1955 Ferguson TEF20 tractor
1965 Ferguson 135 tractor
1952 Matchless G80 rigid
1960 BMW R60
1954 Matchless G80S
1955 Ariel 500 VH
1951 Sunbeam S7DL
1960 Matchless G12 with Watsonian Monza
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Offline renos-a10

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Re: Magneto problem?
« Reply #5 on: 28.03. 2011 09:56 »
Thanks all for you help.I think that my mag need rebuilt and i wiil make.
Thanks again :)
1954 BSA A10 Plunger
Cyprus

Offline wilko

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Re: Magneto problem?
« Reply #6 on: 28.03. 2011 19:47 »
In forty years of Brit bikes, i've only had one mag to break down in this manner. At the moment i've been running a 60 year old mag i bought for 40 dollars for 6,000 miles. They aren't as fragile, including the condensor as people insinuate. There are plenty of other reasons for this symptom.Other people are always ready to spend your money on an expensive mag rebuild.

Online Triton Thrasher

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Re: Magneto problem?
« Reply #7 on: 28.03. 2011 21:15 »

The engine didn't start.

I understand that.

Quote
I check the fuel and all was ok.

Did you try using the tickler button, even with a warm engine? Did fuel run out of the carburettor?


Quote
I charge the spark and that's it.

I do not know what that means and I would almost bet money nobody else does either.  Try to explain it differently.

Offline kiwipom

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Re: Magneto problem?
« Reply #8 on: 29.03. 2011 00:32 »
hi tt/guys,probably "changed the spark plugs" you get used to deciphering gobble de goop after a few forums,cheers,Bob
A10.G.Flash(cafe racer)Honda 250 vtr. Yamaha Virago XV920.

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Offline selva

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Re: Magneto problem?
« Reply #9 on: 29.03. 2011 02:05 »
Hi Guys..
     i have faced same Problem before with my bsa a7.
Whn the engine cooled its easy to start.. but when stop riding,,,
and start again while the engine hot .The engine didn't start.
i got an advice from local old chef. he advice me  to change the condenser.
i ordered the condenser frm

 PETER SCOTT MOTORCYCLES
 44 RAVEL STREET, SEVEN HILLS2147
PH:96241262
EMAIL:QUALMAG@ALPALINK.COM.AU.

after  change the condenser i have solve the problem.

the part number for condenser
400v-/220v-MP
40/070/56

hope this will help you  renos-a10
cheer steven
BSA A7 RIGID 1947(XA7 1352)

Offline renos-a10

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Re: Magneto problem?
« Reply #10 on: 29.03. 2011 08:51 »
Good day guys...

I take out the mag and check it but evrything was ok.May be the problem is that one srew is too close.So i fix this and come back again

Thanks all for a moment
1954 BSA A10 Plunger
Cyprus

Online muskrat

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Re: Magneto problem?
« Reply #11 on: 29.03. 2011 10:09 »
G'day Selva,
                 PS is the MAN down here for magies and dynamos. He was pretty quick on his Rudge as well.
Wilco, you lucky bugga, most magies have been WORKED on by ham fisted fools.
TT, I thought Renos was getting better. My Grandad was a Scott, couldn't understand a word he said  *smile*
Renos, which screw? Not the one holding the handle bars I hope  *smile*
Cheers
'51 A7 plunger, '57 A7SS now A10CR,  '83 CB1100F, 88 FXST .
Australia
Muskys Plunger A7

Offline renos-a10

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Re: Magneto problem?
« Reply #12 on: 29.03. 2011 13:09 »
Sorry guys .... my english is bad.But i try to explain what happen with my baby.
TT  when i said '' check the fuel ''  ( i take out the carb , clean it , replace new gasket ...etc )
And when i said '' change spark ''  ( replace new spark plug )  beacause the spark plug was burn.
Now i hope you understand me.
Muskrat  the screw holding the ignition coil
Thanks anyway all for you help
1954 BSA A10 Plunger
Cyprus

Offline selva

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Re: Magneto problem?
« Reply #13 on: 30.03. 2011 02:07 »
           *smile*G'day. *smile*
 Guys..
 hope everthing fine
 *smile*
cheer
steven selva ;)
BSA A7 RIGID 1947(XA7 1352)

Offline selva

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Re: Magneto problem?
« Reply #14 on: 30.03. 2011 02:22 »
hi guys, *ex*
 its new replacement condenser for
magneto from PETER SCOTT MOTORCYCLES

400v-/220v-MP
40/070/56

cheer stevenselva *smile*

BSA A7 RIGID 1947(XA7 1352)