Twin Magneto Points

pwaltham · Post by **pwaltham** » Mon Jan 10, 2005 12:31 pm

This may seem a daft question but here goes....
I have previously set up car engine ignition timing by using an ohmmeter to see when the points open.
I have tried this on my Model 31 but still get a reading even when the mag points are open.
The bike runs fine.
Am I missing the point (huh!) somewhere?
Should the open points break a circuit of some kind, or are the points assembled incorrectly.
I have checked and think they are as the handbook illustration shows.
Any pearls of wisdom out there?
Thanks
Peter Waltham

lawrence · Post by **lawrence** » Mon Jan 10, 2005 5:47 pm

Bizarre isn't it! I encountered exactly the same thing on my twin and thought I must be mad. I used the old 'ciggy' paper technique though, as stated in the manual and it runs fine. It took two days to find someone who smokes roll-ups though. I was worried I might have had to buy a new packet [:D]

Lawrence [}:)]

itma · Post by **itma** » Mon Jan 10, 2005 6:25 pm

the thinnest blade on your feeler gauge set will do just as well and last longer.
as for finding a roll up paper in this part of the world just head for the nearest growlight shop.........

lawrence · Post by **lawrence** » Mon Jan 10, 2005 9:05 pm

You're not from the Sou'West are you Ken?

Lawrence [}:)]

Biscuit · Post by **Biscuit** » Mon Jan 10, 2005 9:07 pm

It's long time since I played with Electrics/electronics, but with the points open, the condenser/capacitor is still in circuit.................

pwaltham · Post by **pwaltham** » Tue Jan 11, 2005 9:26 am

Lawrence, nice to know I'm not the only one to think I'm going mad.
Ken, I couldn't find any fag papers either so I use aluminium kitchen foil.
Alan, you have solved the problem...... I forgot about the condenser/capacitor......... I was trying to use high technology to sort out a non-existent problem......I'll stick to the old tried and tested ways in future [:)]
Thanks to you all
Peter

itma · Post by **itma** » Tue Jan 11, 2005 6:52 pm

not from it laurence, more like marooned in it....
but you picked up the inference quick enough.....t`aint jus zider `at makes `em look that daft my dear, look.

Dave Walker · Post by **Dave Walker** » Wed Jan 19, 2005 5:16 pm

the capacitor shouldn't conduct DC electricity

Biscuit · Post by **Biscuit** » Thu Jan 20, 2005 7:55 pm

Sitting in my workshop as I write, sits an incontinent BSA 350 Enduro Star ( where do they get these names?) With the body of the capacitor insulated from the engine, and the L/T connection to the coil dis-connected, I get an open circuit when the points open. However the exercise is 'pointless' as shifting the capacitor from it's mounting stud, twists the heel of the moving point, rendering the exercise rather inaccurate. David, as I said my electronics is extremely rusty, but with the body of the capacitor earthed, would it not retain a charge?

Dave Walker · Post by **Dave Walker** » Sun Mar 20, 2005 8:07 pm

yes I guess it would .. perhaps that would be enough charge to confuse the ohm meter ..?