TCI Replacement 2020 It Works

I'm looking for another saw blade to mount a 3mm magnet to see if affects the amount of advance. On the latest video stills I posted (I think from @[URL='http://www.xs650.com/members/yamadudexs650c.21193/']YamadudeXS650C[/URL]t) that showed it from the F mark 15 degrees to about the max advance on a points stator.
It's got to be take your pick. gimpy pickup or magnet or box. since it runs ok on the stock tci then hopefully the loaner floater will solve the issues. The one thing I noticed playing yesterday is that series resistance on the pickup affects the timing.

upload_2020-6-21_16-55-22-png.170369
 
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For Jim May have to ff through some of the 2 hours but some cool info. The gm map sensors they mention I've been looking at for carb syncing.
 
gn250-timing-chart-marked-png.170789


In the diagram above the width of the pulse in Line B1 is derived from the separation of the +ve and -ve spikes in Line A. For a reluctor coil the separation of the two spikes is directly related to the length of the raised metal sensor zone on the outside of the PMA:
PMA.jpg
When you use the stock TCI sensor coil with a magnet it will not product the correct length of pulse that the Gonzo is expecting. This is because the magnet is behaving kind of like a very short reluctor sensor zone.

Jim, may be a larger diameter magnet will help correct for this???
 
But we are getting full advance partly because the magnetic field of the magnet is much bigger than the magnet itself. Compare the photos of oem vs gonzo. There is no magnetic field in a steel reluctor so it has to to be longer. I really don't think the width of signal sets the amount of advance. The processor in the box determines the advance from a lookup table. Both yamadudexs650 and I are getting full advance from a 6mm magnet. I think you are trying to apply analog theories to a digital box.
 
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Additionally the manual that timing chart came from is for a early 80's bike (I think from other sections that I looked at). For instance the timing curve and scope traces I'm seeing looks nothing like that one. I'm sure the original Hitachi box was analogue and a some point PLC based box became cheaper and more accurate.
 
I will be able to know for sure when I get the 3mm magnet another pickup mounted on the test stand.
 

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If it has a Bosch sensor(I'm pretty sure) then 2.5v is atmospheric. 5v max pressure. 0v max vacuum. 5v power supply from 12v usb charger It was mentioned in the oscilloscope video as a way of measuring vacuum.
Ordered a 8 channel pc scope. Will be here Friday.

Read a good portion of the thread on the TZR 250 and the guys web site. I don't think they were able to get one working on a bike .
Looks like they were able to swap the chip from the 30.00 datalogger into the Yamaha CDI. Looks like the CDI on the the watercooled 2strokes was made by Toshiba. Explains why they quit selling the RZ's in the states.
 
If you want to use boost sensors for sync then I suggest using a 1Bar sensor. A very commonly available one is the Unipart GTM6002 or Bosch F 000 99P 003 or Mobiletron MS-E01 (Approx. £17 each). It actually has about 50 different names. On Ignitechs site they have it listed as 82051 but do not mention that is a Meat and Doria Part number. The technical specification curve is out there somewhere and I will at some point be using one to replace the original Mitsubishi on my Virago once I measure its Volt/Pressure curve.

Just remember not to exceed 5 Volts on them.
 
GM map sensor voltages.

1.) 0 in. Hg ...... 4.7 Volts.

2.) 5 in. Hg ...... 3.9 Volts.

3.) 10 in. Hg .... 3.0 Volts.

4.) 20 in. Hg .... 1.1 Volts.
 
Paul Sutton said:
Bosch F 000 99P 003
Click to expand...

Not so good here in the States. I can buy 3 GM sensors for the cost of 1 Bosch. And sadly Bosch stuff gets really homesick over here. The $280.00 Alfa Romero Bosch fuel pump relay comes to mind. And the reason I recommended the Volvo pump relay is that I have several dead ones on my desk and a spare in the glovebox of Ingrid, my 745.
 
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FWIW I just tested my 2 GN250 boxes and both tested NO continuity. Does that mean floating?
Anyone brave enough to have ordered a "Performance" box? If so, how is it?
 
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Yes that is floating. Seems to be the new normal. Interested in how they compare. I haven't seen much difference on the test stand.
Haven't seen the "high performance" version.
 
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I haven't seen the Performance label on any GN boxes.

I got one yesterday which was a grounded box:
Digital Ignition CDI ECU BOX Ignitor for Suzuki GN250 Motorcycle Parts from Ideals 100
on EBay.

I also got a floater, which I've already passed on to someone else.

Update on boxes:

Jeff, 4 boxes........................... all are grounded.
Steve has 1 box (dissected)...... grounded.
Jack, 2 boxes............................ Floating
Jim has 1 box........................... grounded.
Jim has 1 box (dissected)... ....... floating.
Thuban, 2 boxes.........................grounded
Jake650 1 box............................floating
 
I went and found the "racing" box. It's the one I looked at that the specs in the description describe a 2 stroke CDI . Seems sketchy to me.
 
YamadudeXS650C said:
Digital Ignition CDI ECU BOX Ignitor for Suzuki GN250 Motorcycle Parts from Ideals 100
on EBay.
Click to expand...

In the description for this box
"Adopted to condenser diode ignite. Simplifying the structure of the magneto, reducing costs and improving ignition efficiency"
Maybe a way of distinguishing between grounded vs floating. "Simplifying the structure of the magneto" = sales speak for cheaper? A balanced input by nature requires more components. The advantage is better noise rejection.
 

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