Rear mount studs broke, any good fix???

The black wire is not soldered to anything,it is grounded with a MAG mount screw!

Sorry, Dan, my description was lacking a bit. When I said black wire, I should have said earth connection. I was thinking electrically, not physically.
I've attached a pic showing the magneto earth connection.
With the cover off, facing the magneto, the connection is at the top left-hand side of the core, facing you.
Because they're soldering to a heavy piece of metal and no doubt in a hurry to do so, this could easily be a dry solder joint with high resistance, or might be disconnected altogether now, since you said that during testing the resistance sky-rocketed.

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Yes I checked that wire. I read a thread about the wire breaking at the solder point. It is attached well. I think the winding(s) are bad. Just guessing!
 
If you did your resistance measurements at the three solder points and they were as high as you said, then you're not just guessing, it's f'd.
I wonder why so many of these coils fail?
I have a (very old) roll of 0.5mm enamelled copper wire here that has spots all through it where the enamel is no longer adhering properly to the copper, like moisture has got in past the enamel. Maybe the wire in these things is similar. I don't think they're too worried about storing parts outdoors, going by the rust damage I've seen on some parts.

I've got a coil-winding machine, but it can't handle the whole core, only the bobbin itself, otherwise I could wind decent magneto coils for these engines. (Usually, the coil is wound on the bobbin, then the laminations are slid into place and the whole thing is laquered.)
To wind them on my machine, the whole thing would need to be soaked in solvent to loosen the lacquer, then the laminations would need to be slid apart to free the bobbin. After winding, the laminations are then slid back into the bobbin and riveted/screwed and lacqered. Too much work to be practical.
A machine that could clamp the whole core would be easier.
 
I don't think anyone will warranty the MAG, so if I get one that will last, I'm going to attempt to take one apart (counting windings). With the blue and white wires coming out of the outside of the coil & the soldered (ground) looks to be the starting point. :unsure: How many separate windings &/or splices are under that tape? :geek: Maybe I can make a winding tool that works similar to a fishing reel :unsure: I like to piddle with things I don't need right this minute!:whistle: But don't like to mess with things unless absolutely need to!!!:cry: On my rear mount I put another stock mount spacer behind seat tube (between rear tire & seat tube) :unsure: Might give more support, Don't know, can't test it yet :rolleyes: Sorry if I double posted these pics! :rolleyes:
 

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I think the front adapter mount is allowing too much flex! I square the rear mount to the seat post then do the front mount. But the rear mount keeps dropping down the tube,
Yea Dan, I think you may have something there...If that clamp on the front mount is a bit too big you could be slipping enough to snap the rear studs..I have a 1 3/4 down tube and switched to a 1 5/8muffler clamp for front mount like yours..That clamp has to be TIGHT! on the down tube with that mount adapter...or it will twist. I would make sure your clamp is one size less than your tube diameter and tighten the h--- out of it. Or go back to flat mount, crimp the down tube or drill it and dont use spacer for rear mount..I think your front mount might be your probelm........Dont give up, man!!
 
I got the engine tight, & used a second rear spacer mount behind seat tube. Seems to have more clamp power & clamp surface area. But can't try it out. Another MAG went out on me!!! Won't start!
 
Studs Snapping

I'll leave the electrical problems up to others, as I don't pretend to know much about the subject, but I am eager to learn. As far as the snapping stud or mount problems go, the Theory is to Limit the sideways 'flop or twist' of the motor caused by the torque as you accelerate. On all of our cars that we used to drag race, even the ones we didn't race, we Always ran a chain or steel cable from a bolt on the front, left (port) side corner of the block directly to the left main member of the frame. It was taut, and as you mashed the gas, the block wanted to violently flop to the right (starboard), shearing the rear motor mounts. In 1968, GM even issued a recall of their vehicles with V-8 engines to correct this problem...the 'fix' was merely a steel cable to the left frame member.

Check AusieSteve's profile, 2nd & 3rd pics to check out his rear motor mount...a very good example of holding that motor tight so it can transfer all power to the rear wheel only. Ron's 'L-bracket' (Al.Fisherman) seems to do about the same thing. Anyway you can figure that if you keep that engine from lopping over it will eliminate the problem of sheared studs or mounts. I know it is hard and frustrating, and you get madder than heck at everything and everyone; but, I find it always helps to just sit on a low stool and stare at the thing. Pretty soon something will form in your mind, clear as a bell, and once you know the Theory behind what you are looking for, you will have a solution to what is causing the problem, and be able to fix it. Good Luck.
 
Check AusieSteve's profile, 2nd & 3rd pics to check out his rear motor mount...a very good example of holding that motor tight so it can transfer all power to the rear wheel only.

All thanks to Jim and Paul at Sick Bike Parts for a well-thought-out rear mount with the shift-kit. Besides the good vertical length for leverage and the two u-clamps, I forgot to mention that they also purposely drill the two holes that attach to the motor very slightly askew, so that the mount can be pre-loaded during assembly with a large screwdriver while tightening the mounting bolts to minimise engine lean.

The ultimate would be rear and front mounts in that vain.
 
Broken Mounts

Take all the studs out of the engine go down to Ace Hardware and buy 6 mil stainless bolts at the various lengths that you need. The mounts must fit the bike tube curve flush. Use washers to make up space and make sure you use lock washers all around. I like to use rubber pads between to the mounts to obsorb the shock. I will send pictures when I figure out how. I am a new member.
 
The ACE HW store caries 6 x 1.0 Allen head. (black). Which are nicer than the Philips/std head screws they use!:sick: I don't want to use rubber because the Flying Horse engine is smooth running, when it runs. (little vibration) and the clam shell spacer mount is all ready to tight to the seat post, I would not even get an old piece of inner tube in there! :unsure: I think it's a torque issue that's causing stud failure. Going to add a torque stop like Al Fisherman & A Steve use! And see if that cures the problem.:rolleyes: As for attachments I'll PM you!
 
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