Britbike forum Forums British motorcycles in general British motorcycles in general Lucas MO1 Magento Points Carrier

Hi all,

I am currently in the process of a complete restoration / rebuild of a Lucas MO1L Magdyno.

The unit I am working on is from my 1955 Royal Enfield 350 G2 Bullet, although the specific parts I am interested in are the same for many British motorcycle brands from the 1950's.

I have a problem with the fixed points carrier, as shown in the attached photographs. The threads that the fixed points contact stud screw into are stripped, so I am faced with the task of either making a repair with a helicoil (if I can find the necessary gear), or some other way.

Am I correct in thinking that the thread is 5BA? I have measured the diameter with a micrometer and put a thread gauge on it and it seems to be correct for 5BA but I would like someone who knows more about these magnetos to confirm this if possible please.

My preference would be a new carrier but so far I am struggling to find one. There are some on eBay from India, although I would prefer not to go down that route due to import duties and doubts about the quality.

Does anyone know where I could get a new carrier in the UK?

Thanks,

Kev Ev

Just a quick update.

I have made some further investigation with my parts and the thread on the fixed contact point stud is actually 4BA.

I have confirmed this with a brand new 4BA nut.

As there is absolutely no force on the thread, you can use an insert
When you adjust the points make sure you only use magneto spannars that are about 1.5" long so you don't put too much force on the locknut
In a pinch you could square off the underside and glue a 1/2 nut under the housing and use anothe 1/2 nut on top
Some old household power fittings used 4 BA so become a good source of brass 1/2 nuts .