Magneto drive

I use a drive that Pete describes on my Bonneville engine. I removed the impulse but it starts easily with the starter. I don't like the top-drive mags because of the load they put on the small dist. drive gear.
 
I have a wico magnet model a distributor or two. Would probably sell one or both for right price.
Larry Shepard
 
Magnetos are mostly fixed timing since the whole body has to be rotated to change it at all and that could be very problematic for mounting. The housing has to be solid due to the torque it takes to pull the shaft through e-gap. The impulse coupling is only for a retarded spark during start phase. They are basically made for all out throttle usage. Kick back on starting with no impulse coupling may not be a problem with a lower compression engine but it could be for a high compression engine. I've replaced a few busted starters on aircraft engines when the spark retard wasn't working correctly.
 
The impulse starting mechanism also spins the magneto quick enough to get a spark when starting with a hand crank or starter. It winds up a spring and then lets the magneto loose when TDC is reached. When the engine is running a centrifugal device locks out the impulse mechanism.

I see all the magnetos mounted on the high performance engines at Secrets of Speed site mounted on the side and driven by the cam gear.
 
I've got an "SM" Smiley Martin side drive with no mag base, and an unmachined Wells front timing cover and side timing cover.

If you see the attached photo, you can see both.
 

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Sorry, I don't, and sold that setup years ago. I ground off a little of the sheet metal at the pan's edge to insure the mount always sat in the same way. Good luck!
 
Thanks for the reply, taken on board what you said regarding the top drive set up and looking at the side drive instead.
Thanks.
 
Jim Brierley said:
Sorry, I don't, and sold that setup years ago. I ground off a little of the sheet metal at the pan's edge to insure the mount always sat in the same way. Good luck!
Click to expand...

I have used the sump (pan) bolts to mount things like an oil filter but I make my own bolts for the job.
I start with a piece of 1/2" (13 mm) hex stock and turn it down to 5/16" (7.9mm) for the length of the thread on an original bolt and thread it. I then work out how much thread I want on the other end plus about another 8mm and cut the stock. I put the piece back in the lathe facing the other way and turn that end down to the same diameter and thread it. The result is a double ended bolt with the "head" in the middle. By removing one of the original pan bolts and replacing it with mine, I now have a place to attach my bracket. The bolt is put into the block using the "head" in the middle of the bolt and the bracket attached with a nut on the under side.
I hope I have explained that clearly enough. Pictures are not easy to post.
 
Thanks but the question was more aimed at the fabricated Magneto mount that was mentioned, would like to see how it was done/how it was driven?
 
I can't' add any info for your question, but I do have a story about mags.
Back in the 70's and 80's I had an old '62 Harley with a mag, I would reach down and fine tune it while driving, and of course every once in awhile it would light me up like a Christmas tree, tell you what...you were wide awake after that...and sober too.
 
Retson the Racer said:
I've got an "SM" Smiley Martin side drive with no mag base, and an unmachined Wells front timing cover and side timing cover.

If you see the attached photo, you can see both.
Click to expand...

Hi Retson,
Could you possibly post a couple of pics of the foot mount adapter from different angles?
Would be very much appreciated.
Chris.
 
Running a Model XH Wico (foot mount) Magneto side mounted running off the cam gear,
the mag drive gear used appears to be a crank gear which would make the mag run at crank speed.
Do they run a wasted spark system? It has been suggested they use a mag with a 2:1 reduction drive but I can’t find any info on a Wico X model with this.
Can you run at crank speed, is it done this way?
Thanks for any input, I have asked elsewhere also.
 
Most mags like yours do have a 2:1 reduction built in to the mag, so do not run a wasted spark system.
The gear is a crank gear, I hope it is steel and not a cast iron gear? I have broken an iron gear while running Bonneville, not good.
 
http://IMG_4215.JPG

Tried to post pic but failed, I had a good look at the magneto and you are right about the reduction drive, the rotor button itself is geared and drives off the main shaft 2:1.
And yes, I’ll be using a steel crank gear. The are obviously designed to run at crank speed and can handle the revs.
Click to expand...
 
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