ignition timing setting

Alan Jackson /

my old paloma DASL 39.6mm stroke in 1960 the recommended timing setting was 4mm BTDC

should i set this to 2mm with the state of petrol and some tiny improvements to the motors breathing?

the spark plug hole enters the head in at an angle and is to one side.

will i ever see decent power with the spark plug like this?

i suppose this affects the ignition timing and maybe why it is so advanced? am i best converting it to centrally located? or could i even fit another plug hole at the other side?

Re: ignition timing setting

What sort of porting did you do or did you only port match the intake and exhause pipes?

If you adjusted the port event timing then you will want to drastically retard the ignition, however if you just improved the breathing then I would suggest to be no so aggressive for the timing and do perhaps 3mm BTDC. The timing needs to be within a pretty tight parameter, because the actual position of the permanent magnets in the flywheel need to be positioned within an optimum relationship to the iron core of the exciter coil in order to have enough potential when the points open. Too early or too late will not have sufficient magnetic flux through the core to make a lot of electricity.

Make sure the points are open at least 0,4mm at index as well as opening at the timing mark so the coil can be fully saturated when the points open.

Re: ignition timing setting

Alan Jackson /

thanks for that rebel

i forgot about the flux gap on the magneto

im doing another engine with same porting plus a reed valve mod with peak power 7k rpm to suit pipe

the 1961 magneto produces a spark that is only just strong enough and wont power a strobe light and still fire the motor up.

mind you my strobe is from the 1970's i bet nowadays theres led strobes with minimal draw.

Re: ignition timing setting

Time to invest in a inductive pickup strobe

> Alan Jackson Wrote:

> -------------------------------------------------------

> thanks for that rebel

>

> i forgot about the flux gap on the magneto

>

> im doing another engine with same porting plus a reed valve mod with

> peak power 7k rpm to suit pipe

>

> the 1961 magneto produces a spark that is only just strong enough and

> wont power a strobe light and still fire the motor up.

>

> mind you my strobe is from the 1970's i bet nowadays theres led strobes

> with minimal draw.

Re: ignition timing setting

Alan Jackson /

just bought one. powered off a battery, miles brighter.

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