I have a B34 with alternator and a pointless ignition system [transistor]. The rotor is set at the retarded point so I need to know where to set the ignition up in the retarded point. How many degrees is there between the retarded point and fully advanced or inches or mm down the bore from TDC. Hope this make sense to some one.
I would suggest ask the maker of the ignition system for the information, only he will know what range is built into your system.
When you do get the details and set it up,I would strobe it afterwards. Note the maximum advance,I would use no more than 32 degrees as a maximum. The advantage of strobing is that you can see the transition of advance through the rev range, and if the strobe has a rev counter built in the actual rpm where full advance happens.From memory of the several types I've fitted they all seem to have an advance curve of around 28 degrees.
The built in advance feature means no chance of kicking back when starting.The chap who sells the stand alone new BTH electronic magneto's told me this is the main reason for people buying them.
The guy who build this bike is no longer with us so no chance of asking what he did. I had be hankering him to sell it to me for years and I mean years. He wanted to be a one of special MODERN day Gold Star. To put you in the picture it is housed in a wideline featherbed frame, it has transistorized ignition coupled with a 12v Kawasaki alternator a Norton diaphragm clutch operated by hydraulics. It has two row primary chain. Twin disc's on the front and single disc on the rear with racing twin pot Lockheed calipers. It has been stood idle for the last 30 years. I have had to strip the engine and gearbox down and clean it all out as it was run on Castrol 'R' I have rebuilt it now and I am now trying to fathom out the ignition side of things. The little distributor is a Lucas with the markings 40599A and has the solid stator fitted. This obviously has a bob weight in retard position for starting and automatic advance as the revs rise, so this my question where to start positioning the pulse in the retard position ie how for down has the piston to be BTC. Not knowing how far it advances to the 30 degrees at fully advanced. Hope this is not too confusing to you but I am open to all replies. I thank you.
That sounds like an interesting project ! Because you have mechanical advance it should be fairly easy to work it out,use a protractor to see how many degrees the bob weights will advance.Or you could just set it at TDC fully retarded and gradually advance it bit by bit. Have you managed to find out what the dist was fitted to ? I guess even then you won't know if its standard or has different springs or weights.
All I know is the markings on the outside of the Lucas dizzy ie 40599A. But yes I would start from just before TDC and work it back to the optimum running. Looking back when I had a Goldie you started it on fully retarded and a soon as she fired up pushed the lever to fully advanced and it was left there.
It is more common to set the timing in the fully advanced position, the advanced position is much more important than the retarded