Any speculation welcome. I went round to a mate's house last night to try to get his 125 started. It's made by a company called Vulcan, model name "Harrier 125". Couldn't identify much about it except that it seems to be a single cylinder air cooled four stroke. Anyway, I spent about an hour trying to get the bugger started. Checked the oil. Checked the fuel, made sure I could smell fuel in the exhaust while cranking it... Checked battery voltage, checked current was getting to the plug (overloaded my multimeter on 600 V-AC range).

Would it buggery start up?

I decided to give up, as I didn't have a plug wrench to check for a spark even though there was current getting to the plug. Plus I didn't want to flatten the battery by continually firing the starter. I was just digging for my favourite mechanic's phone number to give to the guy when he gave it "one last try".

And it started. It sounded unwilling, but it started. So what's with that? We'd been using the kick and the electric start for about an hour, and I can't work out why it decided to start after consistently not doing for so long. The only changes I made were to switch the fuel to reserve, tighten the top of the carb where the throttle cable enters, tighten the throttle cable at the grip so it ticked over OK... Didn't even spray a drop of WD-40.

Anyone got any ideas? I'm stumped, - can't work out what the problem was at all. Not that it really matters, 'cause we got it running in the end, but I'm curious. I don't think it was any of my tweaking to the fuel / throttle system that did it, 'cause I did all that about 10 minutes before it finally started... Although he tells me it's running smoother now...

Weird.

You're supposed to stand back with a smug grin on your face and say 'I thought that would fix it'


When your mate asks what you did, just say 'It's a trade secret - if I told you I'd have to kill you'

!
Almost impossible to tell you what it was!! Could have been flooded and started when you left it because the fuel had evaporate. That seems the most likely.

I've had similar happen to me before and it was a break in the wiring loom. When I was poking around with bits it must have made a connection again for a short while so I thought I'd fixed it.