Lucas Rita - good spark but engine won't run!

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Nov 17, 2014
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Hi, my latest Project (72 Commando) came with a Lucas Rita and started fine before the restoration. Now having put everything back together i can't get the thing to start.

I have gone through the tests and have a good spark when switching the ignition off with the key, and also when i pass a screwdriver past the pick up. In spite of this the bike won't start!

Initially i had the timing set up so that at 28 Degrees the lobe on the reluctor and the pick-up were in line....bike didn't start. I found these instructions online (https://www.britishonly.com/pdf/rita/fittinginstructions-nortoncommando.pdf) which state that the lobe on the reluctor must be approx 5 mm before the lobe on the pick-up at 28 Degrees. Made the necessary changes to no avail...the bike still won't start.

I have a paddock startermotor - when i rotate the engine with that it rotates nice and freely but makes absolutely no sign of firing (no Backfiring etc.). When i open the throttle, the engine becomes rough and labored and still makes no sign of combustion whatsoever.

Afterwards checked the (new) spark plugs....which smell of petrol but show absolutely no sign of combustion.

Obviously i am doing something wrong, but have absolutely no idea what it could be. I have heard that the Rita is a good system so i would really like to keep it if possible - any help finding the problem would be greatly appreciated.
 
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Does it spark with the plugs out but earthed to the head and the engine kicked over.
 

L.A.B.

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Are you sure you are using the correct rotor timing mark?
 

Fast Eddie

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Have you remembered that the cam goes backwards (anti clockwise) on a Norton? So, 5mm before the pick up is 5mm in the opposite direction to what it would be on a Triumph etc.
 
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Nov 17, 2014
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Hi Folks, thanks for the flurry of answers!

@kommando,

i have only tested it with the spark plug out and earthed to the head whilst passing a screwdriver passt the pick- up and when switching the ignition on and off....i will test it immediately by kicking as well.

Hi LAB,

As far as my memory serves me correctly there is only one mark on my rotor....will check and post back in 5 mins.

@Fast Eddie,

Yes, the lobe on the reluctor is 5mm above the lobe on the pickup (as shown in the diagram in that link which i posted)

Will post again in 5 mins
 
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Hi,

@ Kommando, I have a spark when kicking.

@LAB, you are right.....there are two marks on my rotor.....i will time it to the other one right now and try to start again.

Thanks
 
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Nov 17, 2014
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Thanks everybody....i timed it to the other mark as LAB suggested and i have combustion. :)

While i am here a subject off-topic:

Does anyone have any idea of the current uk market value of a Triumph Speed Twin 1938 (Girder Forks) as i have one on my radar and am already pondering whether i can squeeze yet another bike in here :(
 
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With the plugs out its easy to see where the pistons are up or down, good to see easy fix we all do it sometimes.
 
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