Starter solenoid

[Neill C]

Hi all. I've been having problems with my starter solenoid. The ignition sometimes doesn't light up until I give the solenoid a tap. Once I've tap it a couple of times the ignition lights up and off I go. Today the bike cut out and I had to get off and rattle it to get going again. I thought the solenoid was just a switch to get the starter spinning. Any thoughts on why this affects the ignition?

[Bryanj]

It shouldnt, the only connection is through the small red wire from terminal with battery cable to fuse

[McCabe-Thiele (Ted)]

Sounds like a problem with the ignition circuit not the solenoid as that only operates the starter motor when you press the start button. I would be checking the fuse box at the back where the wires are soldered on.

Update: Plus even suspect the ignition switch itself.

[Bryanj]

What exact model is it as 500 and 550 differ a lot

[Neill C]

It's a 550F

[Bryanj]

In that cas the fuse box itself is suspect as the clips get warm, loose tension on the fuse end, get warmer still, melt the plastic and even the solder connections.
Also ignition switches have been known to give intermittent contact

[Neill C]

Thanks. The joys of owning a 47 year old bike are never ending!

[Bryanj]

Great innit, but they failed40 yr ago as well

[Neill C]

I replaced the solenoid and all seems wellxat the moment. Apart from the two main terminals two small wires come off the side of it so I'm wondering if they had anything to do with it?

[Bryanj]

Nope, they are the energizing circuit, one goes to earth the other gets power when the starter button is pushed on yours ( opposie on 500).
I suspect the small red wire to loom had a bad connection OR moving all the stuff about made a better(temporarily) connection in fuse box

[Neill C]

Damn!