Hi hello everyone I’m new , I have just bought a 1950 c , it hasn’t run for a few years so I’m cleaning out the carbs changing the oil etc before I attempt to start it , it has a manual mag on it which I know is wrong , and there is another mag in the spares along with the auto advance unit , this might sound daft but bear with me , which way do I move the lever to start it ? Cable slack or tight ? I do intend to replace the mag . What’s the recommendation do I go bth mag or distributor , thanks
ET: Engine (Twin) Vincent c mag
- Thread starter Shilton
- Start date
Mag turns anti clockwise so look at the way pulling the lever moves the ring inside the cover normally pulling the cable moves the cam ring anticlock wise so the spark occurs later for starting
I would go for a BTH and coil for racing. on the road I dont like all my eggs in one (electrical)basket
having said that I just have acquired a manual advance mag for my next project twin and I am fitting a ATD on it with no advance cable no reason why that wont work so long as the cam ring is fixed
as an aside I am however fitting a screw adjuster on instead so I can adjust the timing by a degree or two dependant on the fuel we get in the future
I would go for a BTH and coil for racing. on the road I dont like all my eggs in one (electrical)basket
having said that I just have acquired a manual advance mag for my next project twin and I am fitting a ATD on it with no advance cable no reason why that wont work so long as the cam ring is fixed
as an aside I am however fitting a screw adjuster on instead so I can adjust the timing by a degree or two dependant on the fuel we get in the future
If you are replacing the mag I would go with a BTH, at least you are not relying on a charging system and battery.
You can of course just run a Lucas magneto if either are good (like Vibrac lock the manual one advanced and fit the ATD if you use that one).
Manual magnetos are worse to start than auto ones due to moving the sparks away from best position rather than altering the whole magneto timing.
When I got my twin it had a BTH fitted, the PO had replaced the Lucas manual magneto as it was hard to start.
Anyway last year I decided to give it the once over everything looked ok but as I was having another remagnetised I had this one done as well, it now has a massive spark compared to before.
You can of course just run a Lucas magneto if either are good (like Vibrac lock the manual one advanced and fit the ATD if you use that one).
Manual magnetos are worse to start than auto ones due to moving the sparks away from best position rather than altering the whole magneto timing.
When I got my twin it had a BTH fitted, the PO had replaced the Lucas manual magneto as it was hard to start.
Anyway last year I decided to give it the once over everything looked ok but as I was having another remagnetised I had this one done as well, it now has a massive spark compared to before.
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I have the auto BTH type mag on my 1950 C and have just had it refurbished (the guys at BTH were brilliant by the way) and I’ve also got new coils. Alton mag was on the bike when I bought it and works fine. My mag is an earlier version but works well, I guess the the latest type have improved upon mine.
Did you mean Alton here?
Sorry, I meant BTH mag was already on there, the dynamo is a Miller.