Another ignition thread.

[Tony Smith]

Riding home and the bike cut dead, no cough, no backfire, one second running fine and then nothing. Let it cool for 5 minutes and it started and ran like a hairy goat missing and back-firing and would not rev past 2,000rpm (which got me home).
 
Tested the coils - they looked ok and tested 1.8ohm primary and 20k ohm secondary. Also when I tried a little manual test powering the coil with 6volts only it was still several minutes before i got the use of my fingers back - reckoned the coil was not the problem.
 
Did the Snowbum ignition amplifier test of making sure there was a combustable mixture in the cylinders and switching the kill switch on and off - got a nice back-fire so for the time being gave the amplifier a pass.

Using a 9 volt battery, a few alligator test leads and a white LED I had kicking around I did an in-situ bean can test and it seemed to be working just fine.

Changed the Ignition amplifier for the cheap Chinese copy I was so proud of finding a year or so back - nothing, not even the snowbum test showed any sign of life.


Went to town and bought a Bosch 0 227 100 137 from a auto parts store and the old girl fired up like brand new. Pulled it all apart, smeared heatsink paste on it and slapped it back together.

Mental note to buy another and keep it with the 2AV54 in the on-board spares.

[montmil]

<snip> Went to town and bought a Bosch 0 227 100 137 from a auto parts store and the old girl fired up like brand new. Pulled it all apart, smeared heatsink paste on it and slapped it back together.

That exact same Bosch part is OEM in my 1986 VW Cabriolet. The Hall sensor in the distributor is also same as our Bean-O can units. Opens the possibility of salvaging an older VW distributor from an auto bone yard if your can goes Tango Uniform.

[Tony Smith]

Monty

Given that the 2AV54 is back in production in China and the part would cost less than a wrecker would want for a ancient VW/Audi/Porsche/Volvo/SAAB etc distributor, I think the days of that kind of salvage is over.

And to be truthful I reckon the Siemens HKZ101 part is a superior replacement because it can be bolted in whereas the 2AV54 requires rivetting. I do not have a rivet tool so I had to much about drilling the end of a 5mm bolt and then hardening it to make the "dolly" I then used a fine hardened "centre-punch" to deform the top of the rivet. On the balance I'd have been happier using some small stainless steel bolts and threadlock.

I've actually come full circle on my thinking about post 1981 ignition systems. Both my 1978 R100 and the Wife's  1979 R65/80 have mounted Boyer Bransden systems for 30 odd years with zero problems. I bought extra pick-up coils which have never been used, I've never bothered with a spare control box as these bikes could be reverted to points in a matter of minutes (albeit that neither of them would have a work advance-retard mechanism).
 
It's that last bit that has always convinced me as to the superiority of the BB system - automatic spark advance. Given the costs if my R65 ignition pays up on me again I will convert it to Boyer ignition and be done with it I think.