Author Topic: misfire under acceleration  (Read 638 times)

Online Guy Wilson

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misfire under acceleration
« on: 24.08. 2015 11:27 »
.I have a 52/53 Gold Flash that was dismantled and spread around Kenya. Its not now pretty much reunited with all its original bits and sort of road worthy (always open to interpretation in Kenya)
It was running fine around the garden but when I took it out on the road it misfires under acceleration.
I was reading an older post on magnetos (They are a mystery to me and I'd like to change that) It suggested  reducing the spark plug gap as a temporary fix as the misfire is a sign of imminent magneto failure or brush failure. I'd like to understand what may b about to happen if that is the case.Can anyone explain it simply?
Guy
Kenya

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Re: misfire under acceleration
« Reply #1 on: 24.08. 2015 12:51 »
When magnetos fail they often give you a bit of warning, one such warning is a misfire! Also the bike is difficult to start when hot. If you haven't given the magneto any attention it would be worth giving it a general 'service' which is in the scope of most owners and can be undertaken without removing it from the bike. i.e clean the points and check the gap, remove the pickups and make sure both brushes are clean and free to move in their slots, give the slip ring a clean whist the pickups are out, clean the HT leads and check the plug caps and connections at both ends of the HT leads, remove the earth brush and make sure it is free in its pod and not oily.
Priory Magnetos Ltd - A10 spares, magneto and dynamo refurbs. www.priorymagnetos.co.uk

Online Guy Wilson

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Re: misfire under acceleration
« Reply #2 on: 24.08. 2015 15:33 »
thank you, that's what I'll do before i get into anything more serious. I have a spare of a later bike. I'll check that one out as well. The one on the bike at the moment won't have any sort of service other than a general cleaning for at least 20 years..
Guy

Online Guy Wilson

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Re: misfire under acceleration
« Reply #3 on: 25.08. 2015 13:56 »
Discovered the exhaust tappet was way out on the right hand side, the side of the miss. Its adjusted correctly now. Once I've run on the road, I'll approach the magneto if its still missing.
Guy

Online Guy Wilson

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Re: misfire under acceleration
« Reply #4 on: 31.08. 2015 17:54 »
Correct tappet setting seems to have solved most of the miss fire...I'll try and get a good run in at the weekend,
Guy
Kenya

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Re: misfire under acceleration
« Reply #5 on: 31.08. 2015 18:21 »
Sounds promising!
Priory Magnetos Ltd - A10 spares, magneto and dynamo refurbs. www.priorymagnetos.co.uk