1958 model 30 magneto

Ironhead · Post by **Ironhead** » Thu Jul 09, 2009 11:23 pm

Hello All, I have another question not to many for one night I hope.(Anyway Tele`s Rubbish in the summer)
Would my magneto have automatic advanced retard for the model year,
If not would one with automatic adv. ret. work OK mine looks jiggered.
Alex.
P S would you buy one on E-Bay

Duncan · Post by **Duncan** » Thu Jul 09, 2009 11:45 pm

Alex, I believe all of the twins had manual magneto’s fitted, I am not sure if there is room for the auto mechanism under the timing case, if you are concerned about operating a manual one don’t be it only needs to be retarded to start and even then it is not 100% necessary, I borrowed a BSA magneto (no manual A/R) to go to the Dutch IJR a couple of years ago and ran it with fixed timing and the bike started fine, it was a good magneto however with a strong spark.

At the risk of being denounced a heretic I am now running on a modified Fiat 500 distributor ( with auto A/R) and believe the bike is better/smoother at slow “Run” type speeds.

As for e-bay you pay your money and take your choice, however it may be worth contacting Tony Cooper first (sorry I do not have his details to have but they have been posted here before) and see if he will sell you refurbished one without an exchange unit.

rex.webb · Post by **rex.webb** » Thu Jul 09, 2009 11:50 pm

NOW NOW THERE IRON HEAD ???
That there Micky Mouse is mine ??
Can i have him back please??
Ride with Care and Live Long.

Tolly · Post by **Tolly** » Fri Jul 10, 2009 11:24 pm

Alex, my '57 G11 has an auto adv/ret drive gear as the mag has no manual fixtures, I do not know if this is correct as I have only had the bike for the past 7 years but it works fine. I know Itma doesn't like twins but he may be able to put you right.

wilko · Post by **wilko** » Sat Jul 11, 2009 2:20 am

Show us a picture. Have not come across an auto advance on a twin before? Even if it's off another make it would have to have the right gear pitch and tooth count?

Tolly · Post by **Tolly** » Sat Jul 11, 2009 9:42 pm

Unfortunately it's behind the timing cover Wilko, but when it comes off and I remember I will take a photo. Saying that the outer part of the gear (teeth etc.) were identical to the old "fixed" gear, that's why I'm not sure if the mag is the correct one or not. When I bought the bike it was running like a pig and on checking the timing found a fixed gear driving the mag which does not have manual adv/ret. Having located an auto gear it ran much better.

wilko · Post by **wilko** » Sun Jul 12, 2009 1:00 am

Well i'll be a monkeys uncle!! Never seen one. Could you get your X-Ray camera out, i'm intrigued!

Tolly · Post by **Tolly** » Sun Jul 12, 2009 1:35 pm

Wilko, it's due for a service very soon, if I get time I'll whip the cover off and take a photo. I thought these gears were quite common as I had no problems finding this one.

Don Madden · Post by **Don Madden** » Sun Jul 12, 2009 5:22 pm

When you get the advance unit in hand, compare the teeth & mesh with the intermediate gear very carefully. I have never seen one for our twins but have seen various dyno drive gears. Some have the same tooth count as the AMC gear but different tooth profile so mesh poorly. Cheers, Don.

wilko · Post by **wilko** » Mon Jul 13, 2009 2:57 am

Uh Oh!Tolly won't be getting any sleep tonight. Is his mesh correct? Might get a picture sooner now. Your a devil Don!