Old Brown

That is how it works as far as I can tell. Like I say the timing is spot on at idle and jitters a little at higher revs. Just doesn't advance. Main difference I can see is the magnet on the newer bikes covers 15-20 degrees instead of the dot on the 650. Once I get her closer to roadworthy I will explore some options. I'm looking on fleabay for a spare pickup coil to see how it is constructed. I'm thinking that making the pickup coil cover a longer arc or a arced magnet might get the advance working.
 
I did find a place that sells rattle cans of Toyota smoked mesquite brown paint . That is the color that is the closest to the TXA cinnamon brown that I've seen. If anyone is out riding their TXA be on the lookout for Toyotas to see how close it is. Just curious
 
Correct me if I'm wrong but on that 700 set up the pickups should be "Seeing" the magnet through those two holes in the shield?
 
xj pickup.jpg
the 700 looks more like a pamco only on the end of the crank. The alternator is behind the cylinders
 
I've been looking for my impact screwdriver so I can get the damn peanut butter screws off the xj cover so I can get a look at the pickups and the magnets. It would be nice to widen the selection of used TCI boxes if I can get this to work properly.
The main thing is I got her to run so I can get the carbs straitened out . I going to Hurst next week to pickup a set of 2 into 1 pipes from wannabridin so I can start working on the jetting. I'm excited about the pipes because they look idenical to the 2 into 1 Hooker Headers that were on Old Brown when I bought her. A full circle thing.
 
This a bit vague but think I remember the two windows are the timing here.
Crank fired the two pick ups are for the different piston sets; one set is TDC while the other is BDC so you would only use ONE pick up and fire ONE coil That TCI uses two pickups to fire TWO coils. It's really TWO TCI's in one box.

xj pickupa.jpg
 
I did find that using the black wire as the hot and the orange as common is what got it going. Perhaps why previous attempts at substituting TCI's from other bikes failed. I did try hooking the grey to the TCI input will it was running didn't affect the timing.
 
Yes you are right. I'm just using one side of it. One xj coil to fire both 650 plus wasted spark style.

A quote from the xj guide I'm using.
" This spinning rotor disc has a small magnet embedded within it's outer tip, and as that outer tip rotates past the fixed magnets within the PICK-UP COILS, the interaction of magnetic fields triggers a small voltage in the pick-up coil wires that lead to the TCI UNIT."

Pretty much what we have on the 650 TCI. Head scratcher.
 
I might try using the advanced pickup coil grey wire as common and the black as hot. It sure seems that the magnet and pickup coil would be at the advanced position and the processor would wait x milliseconds to signal the spark till it got to the idle timing spot. I'll go out to the barn in awhile and try it .
 
Yes you will need to use one of those pickups and maybe magnet to make it work. But those pickups face IN, they see the end of that rotor/magnet, right? Might be possible to mount that rotor on the end of the crankshaft held on by the charging rotor nut, then mount a pick up on the stator frame facing it?
Or mount a pick up so it faces the existing magnet on the charging rotor. Getting the gap between pick up and magnet as small as what it is on the 700 might be hard to do
It starts getting complex fast.
 
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I don't think the 650 pickups are all that different from the xj pickup. The air cooled 700 pickups of the same year ohm out at 120 like the 650 pickups. I think it is a polarity issue. I just tried grey to common(the advanced pickup) and black to hot. (from pickups). Started up and timing right on the F. Rev up and it retards. ???????
 
late model signal.jpg
I suspect that the holes don't have anything to do with the timing. I think that is a bar magnet on the end. Perhaps at low rpm it triggers when the magnet ends. At higher rpm the box may trigger closer to the beginning of the magnet. As a test If I can find a dead stator maybe a bar magnet jb welded in a position that places the left end of the magnet at the stock 650 magnet location.

Pure speculation on my part. Facing the stator I think the right side of the magnet sets the max advance and the left side the minimum advance. The magnet on the XJ is about the same arc as the timing range arc on the 650.

As a test I may glue a bar magnet to a sanding disk and chuck it in a drill spinning it with magnet passing by the back side of the 650 pickups (the side you see when you are looking at the timing marks).
 
Could be as simple as adding two or three more 650 magnets to the right of the stock one or winding a pickup like the stock 650 with a wider armature.

Yes I know I have too much recliner time on my hands.
 
Quote

Or mount a pick up so it faces the existing magnet on the charging rotor. Getting the gap between pick up and magnet as small as what it is on the 700 might be hard to do
It starts getting complex fast.
650 car alt.jpg
 
Well it looks like the xj rotor is the similar to the 650. Minus the tci magnet and I assume no timing mark. Blank canvas for experimentation. The timing rotor from the xj does resemble a Cuisinart blade
 
Leaving for a circumnavigation of the humidity zone in the morning. First to my hometown of Houston, on to Conroe and the on Sunday to the Metroplex and then home. Stops at Harbor Freight for tire iron and I'm sure a ton of other crap. then on to Conroe for my younger daughter's wedding and then to Hurst to pick up the 2 into ones. Looking forward to seeing my kids and grandkids.
Really looking forward to the tire irons and pipes as that solves 2 outa 3 major issues keeping Old Brown off the road. Paint for the tank is supposed to be here Tuesday.
 

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