Lucas MO1 Mag

vincenttwin

Well Known and Active Forum User
VOC Member
Having a Senior moment ,on a Lucas MO1 Mag single cyl , Is fully advanced having the cable plunger fully in ? (slack cable)
thanks
Peter
 

chankly bore

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Non-VOC Member
Usually advance is taut.Turn the engine to just before points open,slack wire Should be about TDC compression.Pull on slack wire.If points open,advance is taut, taught,tort,or possibly torte.Happy New Year!
 

Comet Rider

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VOC Member
Usually advance is taut.Turn the engine to just before points open,slack wire Should be about TDC compression.Pull on slack wire.If points open,advance is taut, taught,tort,or possibly torte.Happy New Year!

Hi Clanky,

Sorry to contradict you, but on all of out MO1 mag's they are slack wire advance. Only 1 bike that we own is slack wire retarded, and that is a 1922 Raleigh.

SWA is much easier to use whilst riding, as will not do too much engine damage, other than a burst of pinking should it advance un-expectantly on you.

HTH
Neil
 

timetraveller

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VOC Member
I am not sure what an MO1 is but you do not have to endure 'senior moments' with this. If the bike is a Vin then the mag rotates anti-clockwise when viewed from the points end. Whatever the bike just watch the points rotate and move the lever which controls the advance/retard. If the cam ring rotates in the same sense as the points then that is retarding the timing and vice versa. If the advance/retard mechanism is original then it should be tight wire retard but if the manual end was fitted later then it could be either. The danger of a tight wire advance is as follows. Years ago I was competing in the Brighton Speed Trials. In those days the course was either a kilometer or half a mile, I forget which. The course was, and still is, bumpy and the combination of engine vibration and road bumps caused the tight wire advance to slacken off and the timing to retard at about 120 mph. I had to let go of the left hand side of the handlebars and re-advance the timing and then hold it fully advanced until the end of the course. Very stimulating!
 
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nkt267

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VOC Member
Peter. The big problem with MO1's is that they will work pretty much in either rotation. When I rebuilt my BSA B33 the mag was tight wire advance, something I dislike as it is easy for the lever to go to the retard position with out realosing it has happened. I trawled the auto jumbles, no Ebay then, till I found the correct type I needed and changed the points end over. If your points rotate clockwise, looking at the points end, then the advance cable needs to be to the left. If anti clockwise then to the right. I'm still trying to find the correct end for my MS1 mag and having to keep holding the mag lever with the heel of my thumb is a pain..John
 

vincenttwin

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VOC Member
just got a email from Sean Hawker who rebuilt the mag and yes it is a slack wire advance,

thanks for the help ,now I know my timing is close.

hope to get my little New Imperial running next week ,first time in 40 years

Happy New to all

Peter
 
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