Tech Tips: Breaker Points

Personally, here's how I do it - with good results . . .
FIRST:  I make certain point faces are parallel and square to each other - equal distance across from each other.  I bend, pry, tap with hammer & punch, use a needle nose, whatever . . . just get the faces as straight as possible.  If you don't, they are just barely touching at one point - and you may not get a good ground, more arching of spark, more pitting of point's faces, etc . . 
NEXT:  I check my Points Gap on both the "Narrow" and "Wide" lobes.
Magneto Points = .015 to.016 gap (.018 new set)
Cone Points = .020 gap (.022 new set)
If they are a new set of points, I add a couple to compensate for the fiber block wearing.
NOTE:  If the gaps are different on each lobe - I will "true up" the shaft with a small brass hammer or a punch with tape on the end . . . (see below) Otherwise you have (2)different points gap setting for each cylinder - which is lame.  I think my motors run better with equal point gaps.  
I just lightly tap the shaft opposite side I want it to move.  Most of the time it works.  Sometimes the shaft won't move much.  Sometimes it's off quite a bit.  If I can't get the shaft to move, I'll split the difference from each lobe and set my gap at that . . . kinda in the middle.  Example: .022 and .018 - I'll set it around .019 or .020 - ( a shaft with .005+ run-out needs trued )
Spark Plug Gaps
Magneto = .020-.025
Breaker Points = .025-.035
The more powerful your coil, the more you can open up your plug gap.  Most electronic ignitions can jump a .030 or more . . . really get that flame to travel.  The wider gap, the more your coil will "strain" to jump that gap, possibly damaging a stock coil?  I usually run what the H-D Service Manual recommends.  Check your cone points every 10K miles.  Magneto Points last longer.  I've had the same sets of points in my magnetos for about 10 years now - and they all still look good.
ALWAYS grease your cam lobe (fiber block)
With advance weights:
ALWAYS set your timing with weights in advanced position ! Use a screw driver or needle nose to advance your cam to the stop in the direction it turns when engine is running . . .
 5 ohm coils = Points Ignition
3 ohm coils = Electronic Ignition
(You can run a 3 ohm coil with points, you just risk burning your points a bit faster over time . .
See you on the road !

1 comment:

Mitchell Phipps said...

Hey thanks for posting stuff like this.
im 28 and have a magneto run pan. no one else to turn to for information off the computer and it helps alot.
Also makes me want a sportster...thanks.