The other thing is I bet the value of TCI pickups and stators is on the rise.
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TCI Replacement 2020 It Works
- Thread starter Team Junk
- Start date
I checked the resistance across the pickup taps inside the GN box the other day. Don't recall exact... but it was somewhere north of 5 megs, so we need to tread lightly closing that loop. Could easily drown out the signal we want to keep.
Having said that, I'm still not convinced it's causing a problem. If the open loop was "ringing"... why isn't it showing up at idle? The trigger magnet passes the (open looped) advance sensor every rotation. Yet at idle, timing is stable. Why would the noise from the advance coil not cause problems then? Why would it only see the noise when revved to 2500 or so? The noise is being generated every revolution. And if you recall, my last run was only a second or two before it stabilized... vs never stabilizing on my first run.
I'm thinking more bikes running for comparison before we try to fix a problem that might or might not exist. Rudy ( @azman857 ) , can you put up a video of your bike on startup with a timing light on it?
The resistor shunts the signal from the advanced pick to ground. I'm thinking it is shifting the ungrounded center tap far enough away from ground to create a ghost signal in the idle pickup as the magnet passes the advanced pickup. Not sure about the amount of resistance. Has to be low enough to damp the signal pulse and high enough not to overheat the pickup coil from too much current flow. Does not affect the idle pickup coil signal at all.
I'm with you Jim, really looking forward to see the timing video on more bikes to quantify the results. The resistor is more of a chicken soup thing .
Stuff came today to finish the wiring Old Brown so I hope to be shooting timing video myself.
Jim,hoping you are getting some of the somewhat dryer air I have right now. Think it will be the best painting op till fall. Hoping to get my front fender painted tomorrow.
Getting closer to man rating this rocket.
We will be able to tell by the exhaust note.
No problem. We can guesstimate by sound. Mainly we need to see if it's wonky initially or stable on startup when revved.
Bubba method of finding sensor placement. just need the distance of the purple segment.
I may have misunderstood the point, but I’m pretty good at math - if you can give me the angles between the two red lines and the distance from the centre to the blue line, I can tell you how the length of the blue line.
I wouldn't trust that distance between the pickup, and edge of the Stater cut out. Not saying it wouldn't be close enough. would have to assume the TCI and Points stater is exactly the same..............
This is the way i see to do it........
Running a line through the Screw holes in the bracket....Shows the pickup coil is sitting on the edge of the bracket................. The pick up edge is in line with the bracket edge......and places back from the edge towards the screw holes
On the Stater
Where the two Blue lines intersect the degree needs to be found...........
On the Pickup on the Stater.....Measure the distance between the center of the screws and the edge of the bracket.........
Once the degree has been found and the distance between the screws and bracket edge............ Then these 2 measurements can be transferred to a, Points/Type B, Alternator.
Using the distance on the pickup, (between the yellow and blue lines), the pickup coil will be close enough to get it started. make some slots in the bracket of the alternative pickup coil to fine tune the timing
This is the way i see to do it........
Running a line through the Screw holes in the bracket....Shows the pickup coil is sitting on the edge of the bracket................. The pick up edge is in line with the bracket edge......and places back from the edge towards the screw holes
On the Stater
Where the two Blue lines intersect the degree needs to be found...........
On the Pickup on the Stater.....Measure the distance between the center of the screws and the edge of the bracket.........
Once the degree has been found and the distance between the screws and bracket edge............ Then these 2 measurements can be transferred to a, Points/Type B, Alternator.
Using the distance on the pickup, (between the yellow and blue lines), the pickup coil will be close enough to get it started. make some slots in the bracket of the alternative pickup coil to fine tune the timing
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Shots of a 70-79 point stater........and an 80-83 TCI Stater
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I was just trying to keep it bubba simple. No degree wheel, trying to find the center of the window of the stator where the screws would be etc.. It is simple to lay a straight edge over the window and measure to where the center of the pickup should fall. Kinda like Jim's trick for finding the magnet position
A couple of notes
The yellow line should be on the leading edge of the pickup.It's the lead edge that sets the timing.
The holes for the pickup will not be in the stock location.
The holes in the new pickup will need to be sloted to allow for adjustment.
Thankfully I have a nasty stator to experiment with. I'm working on getting the 78 running so that I can run it on the stock points system while experimenting with pickups etc.
A couple of notes
The yellow line should be on the leading edge of the pickup.It's the lead edge that sets the timing.
The holes for the pickup will not be in the stock location.
The holes in the new pickup will need to be sloted to allow for adjustment.
Thankfully I have a nasty stator to experiment with. I'm working on getting the 78 running so that I can run it on the stock points system while experimenting with pickups etc.
To clarify that statement is not exactly true. The Gonzo fires on the start of the negative side of the pulse. I think most of these boxes fire on the transition from positive to negative which happens as the magnet passes the center of the armature, (the red dots). Makes sense because if it triggered on the start of the positive then variations in the magnetic field(size of magnet,strength of the magnet with age, pickup flying height etc.) would influence the spot where it fires.
Seems logical to me, (although electrics are a black box to me), in that there are a lot of recorded problems with a weak magnet that causes starting and running issues........Fixed when magnet is replaced.
Yes new holes have to be made in the stater, and slotted on the pickup, for final tuning.... as i mentioned in post #390
Edit for my diagrams relating to the yellow line..........The pickup should be on the edge of the yellow line and placed back towards the Blue line
Don't need a degree wheel. Once the line across the Stater mount holes is made, lay a protractor, (or a 90 degree protractor, 180 cut in half), on the line to get an angle of the line for the TCI pickup mount holes.........measure and mark A (in all three pics), That line, (Yellow), then is the back, (for the want of a better word), edge of the Trigger.........
.I cant get access to a TCI stater to use for a reference...........thats why i need an angle/degree number............Not right now........just a thing, when ever
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Morning Skull. Always so interesting talking to someone that's already in tomorrow.
Just a slight correction, the leading edge of the pickup looking at the side of the pickup that faces the rotor is towards the middle of the pickup assembly (the rotor spins counter clockwise, anti clockwise for citizens of the empire).
Just a slight correction, the leading edge of the pickup looking at the side of the pickup that faces the rotor is towards the middle of the pickup assembly (the rotor spins counter clockwise, anti clockwise for citizens of the empire).
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Time travel is a wonderful thing..............Yes!!!!...got my leading edge backwards.........correction will be done...........we have cyclones, (clockwise) and you have hurricanes, (anticlockwise), no wounder you up on this...
I hear the toilets swirl opposite also.
Makes you wonder what would happen if a cyclone in the north Pacific heads south and crosses the equator. Damn, more stuff to research.
The part on the equator stops blowing.....
Had the eye of a Cat 5 cyclone go directly over our community a few years ago.......Cyclone was traveling around 30-35 KPH, took 45 min for the eye to go past........Middle of the night and could see stars when i was looking straight up. the air was unreal, kinda normal at the start then the humidity skyrocketed and sweat was pouring off me, i might as well have been in the rain, my clothes were that wet..................Man i would have loved to have gone out in the eye in the daytime, could imagine walls of cloud and seeing the top of the cyclone, would be like looking up from the bottom of a well, with the sun shining.........
Had the eye of a Cat 5 cyclone go directly over our community a few years ago.......Cyclone was traveling around 30-35 KPH, took 45 min for the eye to go past........Middle of the night and could see stars when i was looking straight up. the air was unreal, kinda normal at the start then the humidity skyrocketed and sweat was pouring off me, i might as well have been in the rain, my clothes were that wet..................Man i would have loved to have gone out in the eye in the daytime, could imagine walls of cloud and seeing the top of the cyclone, would be like looking up from the bottom of a well, with the sun shining.........
Na, the fush from the back to the front.........basin water does though.........
