Forum

[Presto]

Just for fun - found this site advertising contact points for 'classics' - "I have remanufactured old style, top quality points with the original Fibre heels, right diameter Tungsten contacts, correct spring tension and perfect alignment. As they were in the 1930’s, 40’s, 50’s, 60's and 70's.'

[PeteF]

"Tungsten is used but not only hard but difficult to machine"
Good quality carbide tools will machine tungsten.

[geoffro]

I had the same problem on my Crusader Sport and the problem turned out to be a little bit of play in the ignition switch so if you have no amp reading give the key a little wiggle, works for me as ampmeter soon shows a reading.

[Exile]

All of the above makes me glad that I converted Thumper to electronic ignition....

[Dennis C]

Exile it shouldn't, tippi could have cleaned the points and been on his way, electronic ignition stop's and you are stuck.

[ric]

The only reason points can be fixed at the side of the road is because they need to be fixed at the side of the road.

[Dennis C]

Not if you look after your bikes properly, this only happens to poorly maintained bikes.

[jefrs]

PeteF, switch contacts weren't turned, they were stamped out. Dad was the master toolmaker at what became Elliot Automation (GEC), think on the Elliot-Lucas connection. He had a small army of inspectors, toolmakers and machinists fettling the production tools. Nowadays we can use small CNC lathes to rapidly turn and part off such small hard components, even tungsten, but back then it would have been slow and require too much tool resetting. Even now turning tungsten with tungsten carbide wears both components rapidly, which is ok if you only have a few to do. Production is like rivets (they are riveted in place) by stamping on dies, maybe 300 per minute.

[jefrs]

I recently gave away my last set of points and condenser, I couldn't remember which machine they were off so they went to a good home. I don't have anything with points now but I actually like points/condenser-coil systems for their simplicity, ease of setting up and reliability.



The only way I can think of points failing open circuit is if one of the contact pads comes off.

I've seen this where the pad wears right through, and where the rivet simply decided to part company.

This needs a new set but it /can/ be bodged at the side of the road with a small screw replacing the missing contact, a real get you home bodge with a BA cheese-head off something electrical (I think it was a 13A mains plug). Changing the points properly should only take a matter of minutes.

[PeteF]

As always I bow to your superior knowledge in all things J.