Advice from you ignition guru's (points specific)

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At least one screw loose behind the handle bars
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So I bought this 1973 TX650 not long ago with 3800 original miles. Figured I'd take my time and do a slow restore. Bike has mostly been untouched but it definitely sat in someones garage a long time gathering alot of surface rust. Before tearing the bike apart for restoration, I wanted to get the motor running to see if anything mechanical would be needed. Long story short after checking everything motor wise, rebuilding the carbs, getting a new rotor from Jim, updating the reg and rec, I fired it up today. It ran great and was excited. However, I noticed oil pouring out of the right hand cam seal. I'm not talking drips. It was literally running out. No big deal for a first fire up. After adjusting the carbs to get it idling nicely I blipped the throttle a couple of times to get it up to temp to check for other leaks. It then backfired a couple of times and quit running. You could tell something happened to the timing. I then inspected the mechanical advance and noticed one of the retaining clips holding one of the advance weights was MIA, and the weight was sitting crooked on the advance mechanism. Took it all apart and there was no cam seal at all!! The PO must have removed everything, including the original seal, and not put the advance assembly back together very securely. The pics tell the story. The backing plate is buggered up, but worse, the pin that goes into the camshaft is MIA and the camshaft hole that holds the pin is also buggered up. What are my options here? Any suggestions? My first thought is that I wouldn't be able to run any electronic ignition that relies on mechanical advance with that pin hole all sloppy now. Would this require replacing the camshaft?

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I'd guess all that damage was previously done. Prolly buggered up the seal too... which explains why it was missing. Started OK because the po put it back together in roughly the right position. If that hole's wallered out enough it won't hold the pin, your options are pretty limited as far as using the mechanical advance. :(
On a brighter note, did you notice I used brass screws on the rotor... just in case you wanted a crank fired magnet? :whistle:
Yeah... I fixed my crystal ball. :lmao:
 
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I was thinking of going the gonzo route. Good to know on the rotor!
 
Hi
My first thought would be a Ignition not relying on the mechanical advance as Boyer Bransden
If i recall right it does not need the damaged parts

http://www.boyerbransden.com/pdf/KIT00303.pdf

Secondly i think it is possible to salvage ,which may be a cost advantage in the first upstarting event.
The bent part I would try to hammer on I like to use things longer than " Best before "
Perhaps there is a crack but one way is if you have a socket for the hole and then press on it in a bench vice
or hammer on it .. Soft hammer and soft vice. perhaps a pipe . in the hole
Perhaps a weld is needed but nothing major .. .. assuming it is that type steel
If it was a rare part one could turn a new ring and take off the damaged and weld in a new .but then
the Boyer is in this case a more natural choice.
We are not talking a part with exact tolerances
The pin and hole is more difficult to evaluate Cant exactly see on the picture If half the dept is left some pin will stick. . my first guess is use of some locking chemical
For a larger pin i would look at shafts from drills .. cutting of a bit that has grip .grind it conic in the point and drive it in with the locking compound
But again it depends on the depth of the damage.

Please ask vendors about this case but perhaps that one

https://www.henkel-adhesives.com/us/en/product/retaining-compounds/loctite_648.html

And hard solder can be an option .need for acetylene torch ..which also can help in the adjusting of the bent part.

The mechanical advance is perhaps the worst design on these bikes .. So a change will most likely come after a while.
 
The backing plate is toast. The bent piece is cracked all the way through and it doesn't appear to be a weldable metal. It almost looks like some sort of cast metal. Quite brittle. I was also thinking of drilling the camshaft pin hole all the way through to give the pin more depth, then fill the hole with maybe a hard 2 part epoxy or a hardened solder and redrill? Any risk in having the pin ride up against the points shaft if I drill the hole through? Backing plate could probably be obtained used, so not too worried about that.
 
The backing plate is toast. The bent piece is cracked all the way through and it doesn't appear to be a weldable metal. It almost looks like some sort of cast metal. Quite brittle. I was also thinking of drilling the camshaft pin hole all the way through to give the pin more depth, then fill the hole with maybe a hard 2 part epoxy or a hardened solder and redrill? Any risk in having the pin ride up against the points shaft if I drill the hole through? Backing plate could probably be obtained used, so not too worried about that.

Aeehhh..hhh that is drilling in the camshaft which is hardened at least at some points and most likely of hard steel.
There is also a bushing for the advance axle inside .I don't know how far it extends.
But that bushing can be taken out with a long soft drift .. if one wants to drill. It is not easy but I have done it.
I believe it is difficult . to get a usable ( Round ) hole with small diameter drill in a hardened part holding a hand machine
but it perhaps is doable.
With some measurements not drilling all the way through.
Not having the parts here before me -- my guess is that I would not try to drill. And I have worked with sheet metal and are used with handheld machines.
Thinking out loud Larger hole ? ..and a stepped pin ? one diameter slightly larger than stock into the hole
 
Problem one with drilling the pin hole in the camshaft is that you're going to have to remove the camshaft, and if you do that, you might as well just replace it with a used camshaft, they aren't that expensive.
Problem, two, is that you're still going to need an advance unit. Do you already have one lying around? If not, good luck finding one for under $90.

This is the perfect opportunity to go to a virtually maintenance-free TCI. I'll sell you a guaranteed good TCI for 85, a guaranteed good reg/rec for 15, and a guaranteed good dual coil for 25. Buy all three, and shipping is free.
Now, all you need to do is to convince Jim to swap the rotor you bought from him for a TCI rotor. Or, add a magnet to your rotor -- there's plenty of info on doing that. Finally, you'll need to buy a TCI stator -- I might be able to help you on the stator too. And make a couple pretty simple changes to your wiring.
Then, you can sell your now un-needed advance rod, and your damaged advance unit, to me.
 
I actually have a working spare TCI, rotor, stator, reg/rec and dual coil. Was just looking for a way to keep it all as stock as possible.
 
Curiosity was gettin' to me, had to go check...
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...drilled a lot easier than I thought it would. But like DogBunny says gotta pull the top end apart to do it, don't think I'd try it freehand in place.
 
Maybe JB Weld the pin in place? I'll have to hunt around, but I think I have an extra advance assemble around here somewhere if you want to give the JB Weld a shot?
 
Or yet another option, if you do decide to pull the top end down. I've got a good 256 cam that I was going to swap the sprocket and use on my build. Since I'm going with an alternative ignition that buggered up hole would bother me, possibly make a trade. Just a thought.
 
Well that was easy... was in the bin marked XS1 ADVANCE.... go figure... :cautious:
Only thing missing is one of the weight clips and the pin. If I'm not mistaken, the pin on the cam side is the same?


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Thinkin' it through... the pin's just there for alignment, it's the nut that secures the housing in place. I think I'd go with the JB epoxied pin. There's really no forces on it once it's secured. I don't think the advance (housing) would move any.
 
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Thanks Beags for giving that drill a go! Yeah, was out in my shop and I made a pin slightly larger than stock out of the butt end of a drill bit. Should be strong enough. Will try JB weld with it. There does seem to be enough meat in the camshaft to hold it in place, and with a bit of JB weld it might just do the trick. The backing plate does appear to be stamped steel. I was surprised though at how little it would give before breaking apart. For being stamped steal one would think it would bend a bit more. I'll try welding it up tomorrow.
 
@Jim, I actually have a couple spare pins from a kit when I bought an XSCharge unit that subsequently fried a few years back. If'n you're interested in parting with that advance plate/mechanism, let me know.
 
@Jim, I actually have a couple spare pins from a kit when I bought an XSCharge unit that subsequently fried a few years back. If'n you're interested in parting with that advance plate/mechanism, let me know.
PM on it's way.
 
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