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Motorcycle Discussions => British Bikes => Topic started by: jdmetcalf on November 08, 2014, 01:17:38 PM

Title: BSA B25 Starfire 1978 contact breaker
Post by: jdmetcalf on November 08, 2014, 01:17:38 PM

Hi,
Does anyone know why the 1958 B25 Starfire contact breaker does not have a condenser wired in?  It runs without it and the wiring diagram for 1968-71 models does not show a condenser, although the previous and later models both have a condenser.
Thanks, JD.

Title: Re: BSA B25 Starfire 1978 contact breaker
Post by: Boo on February 13, 2015, 07:38:07 PM

1958 should be a C15 with a mushroom ignition at the rear of the barrel. It should have a condenser next to the points. Maybe it has been fitted to the coil instead, same thing, other end of the same wire that's all. No condenser will give a huge spark at the points and small spark at the plug. It will also make short work of welding the points together.

Title: Re: BSA B25 Starfire 1978 contact breaker
Post by: john.k on February 21, 2015, 10:55:00 AM

A condenser is essential,it may be fitted between the coil terminal and earth,or anywhere between the coil points lead and earth,including inside the ignition unit.Without a condenser you get very weak spark,and the engine wont rev,and the points burn. Unless an electronic unit has been fitted,of course.Regards John.