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[Adrian]

Finding SR1 magnetos isn't hard, I think you will find cheaper ones. The good news is that they bolt straight onto the Indian Bullet crankcase Alan, just as they did with the 1956-on Redditch Bullets. When Redditch swapped to contact breaker drives the crankcase dimensions weren't changed, and were also faithfully copied by RE India until the end of the classic model Bullet.



If you are happy running on fixed advance, the Indian contact breaker drive gear fits straight onto the magneto drive shaft. If you want the automatic advance and retard mechanism shown attached to the back of the magneto in Alan's picture, the bad news is that they can be a lot harder to find (though there are still some out there).



OTHERWISE (if money is no object) a BT-H electronic magneto can be used, these have automatic advance/retard built in electronically. Sadly BT-H do not YET offer a direct replacement for the SR1 magneto, but their other models "can be made to fit". Ask Bullet Whisperer...







A.

[John M]

I'll see if I can upload a couple more images that give a better view of the swinging arm pivot. I welded in the inserts for the pivots as there isn't sufficient room for the huge nuts that normally keep them in place. Make sure that you use the correct ones for your swinging arm as there are two sizes.

[enfield_trials]

for trials bike project. magneto is good and tidy solution. and get rid of all batteries coil stuff




Even you can use electronic ignition in magneto body like thorspark

http://www.sussexmotorcycles.com/thorspark.html




my friend have used with them no problem.

[Adrian]

I wouldn't want to criticise Thorspark as a product, but once you modify the magneto in this way you need an external power source to run the thing, my preference would be for a working magneto as a self-generating system. It doesn't have to be the SR1, either. All pre-EFI/UCE Indian Bullets still have provision for the steel straps to hold down a Lucas N1 magneto (or MO1 magdyno), so if you could sort out a mounting plate to get the magneto spindle to the correct height that is another possibility, plus you get manual advance and retard control for the ignition.

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The other solution is to use something crank-mounted. Our hosts list the PVL competition CDI ignition which simply replaces the Bullet's alternator, no battery needed. Elextrex World sell something similar, either in ignition-only or ignition plus lighting coil versions. This set-up offers more accurate ignition timing as there is no variance due to slop in the long train of timing pinions.



The budget solution is to use the existing alternator to run a battery-less 12V ignition. It just needs a healthy alternator and reg/rectifier, replace the battery with a suitable capacitor. Works well with points ignition, but don't attempt it with a Mk3 Boyer Bransden! The Mk4 or the Pazon Surefire ignitions are better able to cope with lower starting voltages which are likely at kick-over speeds, so these might work.



A.

[enfield_trials]

Thanks Adrian for the info. I am not expert on Electronic ignitions.



i might go for last solution you describe. some nice idea for coming projects Thanks again

[John M]

I use a Lucas SR1 magneto on mine and it has been faultless for over 9 years, other than once, when I submerged it in a deep ford.
I think that the SR1 is one of the most reliable magnetos that Lucas made, (I think that it was the last model they made) and all the parts can be swapped over in minutes. There is none of the re-winding issues to replace the condenser that you get on older models as it uses a conventional separate condenser.
If you can’t find an auto-advance unit they will work satisfactorily on fixed timing.

[John M]

Let's see if I've sorted this posting image business.

[John M]

Nope!!!

[enfield_trials]

John try using FULL Image html code








do you have separate dynamo on SR1 mageneto. ? handsome bike

[enfield_trials]

bit off topic . do you think gearbox in this condition can be restored.