['45 WD CO]

Gents,

Before I begin my exploration with "no Spark" on my '43 WD CO, does someone have a list of top reasons?  I rebuilt the magneto last year and all was going well, until ,.....  I assume the battery has nothing to do with anything, since it has a magneto?  If that's the case, then I'm left with coil and rectifier? Thanks so much.  Bill

[malky]

Hi Bill.
The mag works independent from the charging system, lights etc. Here's a simple list. You may have done this already, so I don't mean to insult your abilities in any way.
1 if your bike has a kill switch/button follow the wire down to the mag and disconnect it.
2 if no spark try another plug.
3 if no spark, remove plug cap if fitted, ensure the plug lead end is clean ie; no wires hanging out, jam the plug lead end between two of the cylinder fins and kick over the engine and check for a spark, if you see a good healthy blue spark jumping from the lead end to the fins,then this is usually enough to get the bike running. If there is no spark: in a darkened area get someone else to kick over the bike while you visually check the length of the plug lead for any tracking/arcing, with the plug lead following its normal route as if the engine was running.
4 if still no spark, first check the point's are assembled properly and any screws nuts etc haven't slackened off, check that the point's are clean and opening and closing properly, you can clean your points with a purpose made point's/magneto file without dismantling anything, if your points are operated by a face cam, check that the plunger hasn't seized, this can happen on a bike that has been laid up for a while.
5 if still no spark, follow the plug lead down to where it is attached to the mag, this is usually a bakelite fitting held on by either screws or a spring clip, remove this carefully and check that the spring loaded carbon brush hasn't stuck and is free to move, and check the condition of the slipring inside the magneto which the carbon brush must contact. Depending on what's " in the way" the last two checks may be awkward with the mag still fitted to the bike.
6 these mags also have a condenser which can fail,
It is usually inside the mag,attached to the armature.
If you identify which mag is fitted to your bike and do a search on Google, there is no end of exploded diagrams etc which are a great help. Hope this has been of some use. This check method has worked for me in the past and if each check fails then it usually means " mag off time " and off to the repair man.

['45 WD CO]

Thanks so much, Malky.  Working on it now.  Cheers.  Bill

[malky]

Bill. sussex motorcycles.co.uk do an electronic conversion kit for your bike if it fitted with a Lucas mag.

[High On Octane]

I fitted a ThorSpark to my K2F mag.  I was pretty happy with it.