Advance / Retard ignition when hot

Information relating to Matchless and AJS Models built prior to 1939
Diana3899
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Advance / Retard ignition when hot

Post by Diana3899 »

I have a 1937 model 8, 500 cc single and in order to start it from cold I have to retard the ignition lever otherwise I get thrown into the air. Obviously once started I advance the lever to the fully advanced position. My question is this; when the engine is hot should I leave the lever in the advanced position when wanting to restart the engine or should I retard it? One answer could be try it and see but I am reluctant to break my right leg! I would like to know what procedure other members use.
SPRIDDLER
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Re: Advance / Retard ignition when hot

Post by SPRIDDLER »

It is standard practice to retard the timing for starting whether the engine is hot or cold.
With the timing advanced the engine will kick back just the same whether hot or cold.
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Andy G
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Re: Advance / Retard ignition when hot

Post by Andy G »

Diana3899 wrote: Thu Oct 06, 2022 3:13 pm a 1937 model 8,500 cc single
I had to read that twice... :rofl:
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ajscomboman
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Re: Advance / Retard ignition when hot

Post by ajscomboman »

Andy G wrote: Thu Oct 06, 2022 6:00 pm
Diana3899 wrote: Thu Oct 06, 2022 3:13 pm a 1937 model 8,500 cc single
I had to read that twice... :rofl:
Edited so you won't die from laughter! :thumbup:
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Taid
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Re: Advance / Retard ignition when hot

Post by Taid »

I wondered if it was an Alan Millyard special ...
___

Now sold ... 1956 AJS 16MS Bitsa .. HSU 414 .. rebuilt/re-registered 1987
Diana3899
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Re: Advance / Retard ignition when hot

Post by Diana3899 »

Not sure why this was so funny! I am not used to old bikes with manual advance and retard levers. The reason I asked the question was because my old bike is very difficult to start when the engine is hot which I now realise may be a Mag problem. If members feel that their questions however simple are a source of laughter then they will be reluctant to ask any question on the forum. I feel sure that the majority of club members would not want that to happen! Thank you Spriddler for your response which I found very helpful.
Groily
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Re: Advance / Retard ignition when hot

Post by Groily »

The laugh was 'with' you, not a snipe re the substance of the question.
No questions are daft - although some of the answers may be sometimes!

Some people were just tickled by the notion of of an 8.5 litre single cylinder machine, is all - but the fun's gone now because the typo (missing word space that caused the mirth - between '8' and '500') has been inserted into the original post by our learned President . . .

PS - if the engine is hard to start other than at full advance when she's hot, you could well be right, that the mag is starting to fade. it's a classic early sign, on what is sadly a one-way street if one finds oneself on it.
SPRIDDLER
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Re: Advance / Retard ignition when hot

Post by SPRIDDLER »

Diana3899 wrote: Fri Oct 07, 2022 2:30 pm Not sure why this was so funny!
The lads weren't having a poke at you personally or your perfectly reasonable question, but at first glance it did read as though you have a single cylinder 8,500 cc engine which would certainly kick back a bit. ;)

Yes, if you have to set it to full advance to get a decent spark it could well be that the mag is weakening as the strongest spark on any mag occurs at full advance and weakens as it's retarded. Shame really as at my age I'd prefer to have the strongest spark at slow kickstart speed.
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Which taken at the flood............'
Andy G
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Re: Advance / Retard ignition when hot

Post by Andy G »

Diana3899 wrote: Fri Oct 07, 2022 2:30 pm Not sure why this was so funny!
Please accept my apologies Gus, as Spriddler says, no offence intended, I was actually mocking my own eyesight.
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Diana3899
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Re: Advance / Retard ignition when hot

Post by Diana3899 »

Apologies accepted.. Will get the Mag overhauled and hopefully she will start with the ignition retarded and I won't have to risk kickback while trying to start her on advanced ignition.
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