Misc: Ignition B.T.H Magnetos

Bill Thomas

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Am I right that the NEW BT-H mag's don't need any electric feed ,
Just like the old ones ?, Cheers Bill.
 
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highbury731

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Yes. The BT-H is self-generating

Other modern electronic ignition systems like the Pazon need an electric feed.

Paul
 
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vibrac

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Great product pity about the price I have one on the bench waiting to be refurbished after 10 years of Comet racing and I could get another for the road Comet, I have got an old Lucas on the road bike at the moment but I am a bit brassic for project funding at the moment things may improve I may sell the Egli Comet in the spring whan the clouds lift
 

vibrac

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Double edged sword Bill at the moment I am working on a Bike I have stored for 30 years with some parts I have had for 50 but I have spent the last 10 minutes looking for a chuck key. I just put down......... Someone should do something about the second law of thermodynamics :rolleyes:
 

Bill Thomas

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I thought it was just me that had that trouble,
It's very often under my Nose !.
Wish I was as keen as you, I just think a lot !.

The Wife says I am a Thinker, I think that's what She says :D

One day I must have a go at my 560 flywheels, Maybe a job too far ?.
 

norvinmick

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VOC Member
i have had bth mag on my bsa for as long as they where first made may be 20 years or so when i built the black norvin i changed from mag to bth as the mag is in front and will get wet and cut out so i went to bth no problem with water the only problem i had was wen i put new pistons in i put the coils back in place and wired up one wire the other wire had blue tag on it this is the one you timed the engine on.on the coil it has a arrow with b on it. after about 4 to 6 week the bike wood start easy get up 60 65 mph and no faster. i took mag off done every thing i could the lads were saying change the carbs as i was running gardeners i was thinking about it but sent the mag back to bth they said nothing wrong put it back on run it no good above 60 65 mph after another 2weeks i sorted it it was the lead was on the wrong terminal great now i can have a good burn up. i have fitted a bth mag on my other norvin since 2006 4 plug head the black norvin since 2000 and never let me down .
 

kinsellm

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VOC Member
I have modern BTH magneto on a series C Black Shadow. Works well so far, but have only covered about 300 miles so far.
Since about 2010, my brother has used them on his ARIEL HS 500 singles in all weathers, both MK I for scrambling and Mk III for road use. Never had any problems, even with the scramber being breifly submerged under water. On all these bikes we set the plug gap at 20 thou.
 

BigEd

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VOC Forum Moderator
Am I right that the NEW BT-H mag's don't need any electric feed ,
Just like the old ones ?, Cheers Bill.
Tony, the original designer/and manufacturer of the new BT-H magnetos had a stand for several years at the Stafford Show with several of his magnetos displayed on the table. One of the magnetos was one setup for a Vincent twin. A common question asked by interested parties was "what is the spark like?" Tony would pick it up off the table (no wires connected to anything on the table) and spin it by hand producing sparks jumping with a crack 1/4" from the end of the plug leads to the body of the magneto. The next question was often "is it 6 or 12 volt? o_O
 

Bill Thomas

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I was asking for a friend, A new person to Vincent's,
I am out of touch and prefer a Distributor myself.
Cheers Bill.
 
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