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TCI Replacement 2020 It Works
- Thread starter Team Junk
- Start date
OK.... my bad. Second box is here so I rechecked. Jack, looks like your diagram needs correcting.
pos and neg inputs (brown).... 4.58MΩ
neg input to gnd. (blue) 4.76MΩ
pos input to gnd... (green) .4Ω
So... what the diagram is showing is backwards. Swap pos and neg symbols.... and yes, the neg side of the sensor does indeed go to gnd.... so disregard all my "floating input" comments.
Guess I took too many tokes the other night....
pos and neg inputs (brown).... 4.58MΩ
neg input to gnd. (blue) 4.76MΩ
pos input to gnd... (green) .4Ω
So... what the diagram is showing is backwards. Swap pos and neg symbols.... and yes, the neg side of the sensor does indeed go to gnd.... so disregard all my "floating input" comments.
Guess I took too many tokes the other night....
Since it will be necessary to fab some sort of mount for the pickup selecting a nonconductive material and and a ring terminal on one of mounting screws for the other terminal should work.
That's when I do my best work.So... what the diagram is showing is backwards. Swap pos and neg symbols.... and yes, the neg side of the sensor does indeed go to gnd.... so disregard all my "floating input" comments.
Guess I took too many tokes the other night....
I had suspected that they might be reversed. Had a 50-50 shot. Should improve Azman's results. Will fix the pin out. Those 1 wire pickups are everywhere so it will be a good alternative.
I have read that there are two camps on the pickups. Yamaha and Honda use one polarity and Suzuki and Kawasaki the other. I'm sure there there are exceptions.
For anyone curious about the size.... Hitachi TCI on the left, GN250 on the right.
I corrected the pin out labels on the Gonzo
Jim please check my math here on the + and -
Comments welcome
Jack
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Twomany rode his Vegas over to visit and see the gonzo. He took one home to cut open. Nice to have a afternoon of shop talk and hanger flying.
His new two into one pipe sounds awesome. Pretty quite if you soft pedal it and throaty when you stand on it.
We talked about gonzo at lunch and both he and I were shocked at the input resistance on the pickup inputs. He agrees about a damping resistor across the unused leads on the pickup.
My thought is that with that high of a impedance on the input of the gonzo and the much higher gauss magnet the input to the gonzo is way beyond what the box needs to trigger the spark. The box was designed to sense a piece of steel( not a magnet) so the voltage generated with a magnet is much stronger then sensing the lump of steel so the crosstalk in the wiring alone may be enough for the advanced coil to trigger the box at higher rpm.That would explain the hyper advance at higher rpm until it "warms up". I think the box may adjust the gain on the pickup circuit as it sees a high level of noise in the pickup. Kinda like having to turn down the volume to prevent a microphone from feedback.
We talked about gonzo at lunch and both he and I were shocked at the input resistance on the pickup inputs. He agrees about a damping resistor across the unused leads on the pickup.
My thought is that with that high of a impedance on the input of the gonzo and the much higher gauss magnet the input to the gonzo is way beyond what the box needs to trigger the spark. The box was designed to sense a piece of steel( not a magnet) so the voltage generated with a magnet is much stronger then sensing the lump of steel so the crosstalk in the wiring alone may be enough for the advanced coil to trigger the box at higher rpm.That would explain the hyper advance at higher rpm until it "warms up". I think the box may adjust the gain on the pickup circuit as it sees a high level of noise in the pickup. Kinda like having to turn down the volume to prevent a microphone from feedback.
Got a chance to ride a bit today. Had a recently acquired TCI box I needed to test, so I spent about an hour runnin' the GN box and another hr on the new (to me) TCI box. Both worked as they should. Couple of 70-75mph runs back to back and I honestly couldn't tell the difference between the two. I guess now we need to wait for Jack and Twomany to figure out what size resistor we want to try to close the loop on the advance trigger so we can test that but.... I'ma call this a success.
I've started building a run stand for my non-TCI engine so's I can work out the details on converting a pre-80 bike. So hopefully I get that mounted this week and see what I need to make that a runner. All in all a good day.
I've started building a run stand for my non-TCI engine so's I can work out the details on converting a pre-80 bike. So hopefully I get that mounted this week and see what I need to make that a runner. All in all a good day.
I'm thinking a 1156 or the tail light filament of a 1157 wired from the advanced coil ro the common might be a quick and dirty resistor to try. Worst that could happen is popping the filament. That should settle the coil down.
Awesome that you got to get out and do an extended test ride. Nice to have a spare along. If there was to be a problem it surely would of manifested itself running down the highway in the heat. Things a just getting better and better.
Two many and I pulled the ignition covers off my 78 and both sides look great so assuming the starter works I might have a test bed running myself. Want to see if I can get gonzo working on a pma flywheel.
Heat index was hovering around 100°
Life is good.
Yeah, nice visit with Jack and his mud daubers today.
(The mud daubers give on-site welding classes)
Jack handed me one of his GN250 "Gonzo" boxes, with his official okey-dokey to slice it up.
Well, alrighty then.
Looks like I can't stay within the lines.
Oops, I inadvertantly sliced off the top of a large/tall electrolytic cap.
(The mud daubers give on-site welding classes)
Jack handed me one of his GN250 "Gonzo" boxes, with his official okey-dokey to slice it up.
Well, alrighty then.
Looks like I can't stay within the lines.
Oops, I inadvertantly sliced off the top of a large/tall electrolytic cap.
I think I should mention that the tablet on Twomany's Vegas is running software to tune the bikes ECU. When we were leaving to head for the house he's tapping on tablet to adjust his idle. Beats pulling a screwdriver.
Whoops. Damn the bad luck. Almost looks like bamboo in there. Looks like 3 different connectors for output. Standard IC chip with different i/o circuitry to adapt to different bikes . Just as I suspected about these boxes. Actually there are a lot more analog components on the board than I expected. Probably because of the three i/o s. Thanks Twomany. This makes the investigation very interesting.
There's still about an inch of board buried in the potting compound. I would say that the high-voltage, high-current coil driver transistor and associated circuitry are buried in there.
A closer look at the exposed part of the board.
Yup, modern American Ansi/IEEE surface-mount board and silkscreen.
The Blue/White signal (+) wire goes to a pad labeled "PC".
(Anybody's guess what that stands for.)
The first component that "PC" goes to is a 3.9 K resistor.
The Green ground wire goes to a pad labeled "GND".
The Green/White signal (-) wire also goes to a pad labeled "GND".
Flip the board over and check them.
Yup, sure 'nuff, both the Green GND wire and Green/White signal (-) wire are connected to the board's ground plane...
A closer look at the exposed part of the board.
Yup, modern American Ansi/IEEE surface-mount board and silkscreen.
The Blue/White signal (+) wire goes to a pad labeled "PC".
(Anybody's guess what that stands for.)
The first component that "PC" goes to is a 3.9 K resistor.
The Green ground wire goes to a pad labeled "GND".
The Green/White signal (-) wire also goes to a pad labeled "GND".
Flip the board over and check them.
Yup, sure 'nuff, both the Green GND wire and Green/White signal (-) wire are connected to the board's ground plane...
There was some sort of secret smear atop the IC. Tried to clean it to get a better pic.
Would need to examine under the microscope, but I guess that's not necessary here...
Would need to examine under the microscope, but I guess that's not necessary here...
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Recognize the 78l05 voltage regulator probably for the CPU IC.
Mud dabbers I let them make their nests and then when they are hanging on the nest I tie a paper bag on a broom handle, set if on fire and hold it to the nest for a second or two to burn their wings off and then stomp them when they fall to the ground.
Mud dabbers I let them make their nests and then when they are hanging on the nest I tie a paper bag on a broom handle, set if on fire and hold it to the nest for a second or two to burn their wings off and then stomp them when they fall to the ground.
