Fitting a magneto

[tomo256]

I am thinking of fitting a magneto to my generator shovel, but i have a set of panhead cases with the mounting for the rectifier just in front of the points cover, are there any difficulties that i need to be aware of such as modifications that have to be made to the cases. Also are all the Joe Hunt magnetos auto advance, and do they really give a better spark. Oh yeah and does anybody have one for sale.


Cheers

[Limey_Dave]

Do Joe Hunt's give better spark than other mags? Don't know.

Do mags give better spark than coil? Not at normal revs,they're worse esp at low revs.

Unless you are constantly running at high revs, and need to save weight by dumping battery and lights,I can't see the point.

[the_french_owl]

Hi Tomo,

Don't think mags for Pans have advance/retard, not enough room along the cylinder to rotate the mag.

They use the same clamp arrangement as the timer.

Not too sure, but some fins might have to be trimmed...

Mags versus points... Mags were mostly discarded as OEM equipment because of cost compared to a cheap timer... Nothing to do with "is it better or worse"... In most cases, a properly maintained mag's better but most modern folks are just affraid of their supposed complexity.

Patrick

Having used mags and coils for many years I think I am in a good position to comment. A well set up Magneto is good, a poorly set up coil system is poo, and vice versa.
There is a slight difference in the way they work, the mags spark gets better the faster it spins, and the coils gets worse, but for the average Joe, there is very very little diffrence.
Personally, I would stick with what the bike has allready, but I am lazy and wouldn't think the expense or time worth it.

[45Brit]

what 1200shovel and Limey Dave said. I've been looking hard at this for my 45 project, and come to the conclusion that there are better things to spend the money on, and it's a LOT of money.

if you have 12 volt electrics, a modern coil of the Andrews or Accel type, and an auto-advance timer like the one J&P Cycles sells, you have all the sparks a shovelhead will ever want or need. If you don't, then get them. Flog the 6v stuff on eBay, to someone who wants the originality that much. If you have a left-hand advance control, you will need to lock the twistgrip.

spend the rest of the money you haven't spent on a magneto, on a decent carb like a Mikuni, if you don't have one already - assuming you don't have a piano-wire throttle, that is. If you do, get a Bendix if you don't have one already. Flog the Linkert on eBay.

[tomo256]

Yes i am running 12 volt electrics,brand new SU carb, the bike has only just been built, apparently it was one of two that the late Griff from Bristol was building before he tragically passed away a little while back. The reason i was going to put the mag on was just because it would look real neat. But as many of you say i am best sticking with the stock points i will stick with them a little longer.


Regards Tomo256

[45Brit]

This may just be me, but if you have a bike recently built, with 12v electrics and a new SU, I should leave well alone. Someone has already spent the money to do a good upgrade, why waste it?

You will have to take the barrels off and maybe grind the fins to fit a magneto. If your inlet seals are in good condition, your bores are in good shape and you have no serious exhaust leaks, don't disturb them for no useful reason.

I'm not going to argue with Patrick about magnetos and their benefits, because Patrick produces well-engineered bikes and what he does, he does for a good reason

speaking as an engineer by profession, IMHO " 'cos it looks cool" ISN'T a good reason... speaking as an old lag who has been around old bikes for a very long time, disturbing the set-up of a bike recently built by an experienced builder, to do something that "looks cool" isn't a good idea either.

Shovelheads will give you plenty of reason to have a look inside them if you give them time. If you have to take your engine apart, and still think spending several hundred pounds on something you will never get any noticeable benefit of is good value, go ahead.

[kiwidave]

you are not going to get better advice than that from anywhere

[45Brit]

you might also feel that if the builder was of a good reputation, then keeping the bike "as-is" might be a sign of respect for his work.

[kevscrivener]

Originally Posted by 45Brit

Shovelheads will give you plenty of reason to have a look inside them if you give them time.

That has to be one of the best Shovel quotes ever!

I totally agree with you mate, if it's been done right don't mess with it.