Replacing SC36 ICM and converter by an Ignitech DC CDI P2

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MK_WF
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Replacing SC36 ICM and converter by an Ignitech DC CDI P2

Post by MK_WF »

Hi folks,
I just tested/verified the necessary settings on my SC36 and thought some of you may need that sooner or later ...

If you have a faulty ICM and/or converter unit, then you can replace both boxes at once with using an Ignitech DC CDI P2.
The parts will cost you around 200 Eur. incl shipping.

Part list:
- Ignitech DC CDI P2 (http://ignitech.cz/en/vyrobky/dccdip2/dccdip2.htm )
- Ignitech adapter cable (for TCI P4 to Honda 16 terminal connector)
- If you don't want to cut off your converter plug you'll need the Sumitomo HM90 connector: https://shop.touratech.de/steckdose-sum ... -6pol.html

The adapter cable is originally designed for the TCI P4 - the DC CDI P2 unit has different pin coding, so you'll need to exchange two cables/pins.
At the Ignitech connector exchange pin 7 to pin 2. Also Exchange pin 14 and 11.
The result will look like this (I installed bullet connectors to be able to switch between TCI/CDI):
Image

Then unplug the ignition converter unit. You can either cut off the plug and solder together
black/yellow and yellow/blue
black/blue and blue/yellow
or you get the above Sumitomo HM90 connector and build something like this:
Image
Image

Then connect the DC CDI to the ICM connector using the above adaptor.
Connect the unit to your PC (USB to serial needed; cable needs the right drivers) and use the following settings:
Image
Image
Image

The wiring will look like this:
(Note that you can connect pin1 and 10 directly to yellow/blue and blue/yellow at the converter connection.)
Cylinder 1 means rear, cylinder 2 is front
Image

I can confirm that the described setup worked on my (non HISS) '98 SC36.
I'm using the pictured ignition map for quite some time and had no issues yet.

All Ignitechs offer some more features than the stock ignition.
On my bike I'm using the shifter-option
Image
and I'm about to build some "EXUP" type exhaust that can be controlled by the Igni
Image
(butterfly donated from a Ducati Hypermotard)
Bye
Martin
tony.mon
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Re: Replacing SC36 ICM and converter by an Ignitech DC CDI P

Post by tony.mon »

Very interesting map inputs; several are not in the sequence, are these as a result of fine-tuning? What symptoms did you get to let you know you needed to tweak in some places?

Well done :clap:
and cheap, too.

Is there a blipper module input for downshifts?
It's not falling off, it's an upgrade opportunity.
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sirch345
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Re: Replacing SC36 ICM and converter by an Ignitech DC CDI P

Post by sirch345 »

Well done :clap:
That could be really helpful, thanks for posting that :thumbup:

Chris.
mik_str
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Re: Replacing SC36 ICM and converter by an Ignitech DC CDI P

Post by mik_str »

Very cool.

I had tried a couple of Ignitech boxes a while back but could never get them to work (though I think that was due to an electrical gremlin that I have since fixed). ON a positive note, Ignitech stood behind their product.

Keep us posted on how things develop :)

Oh yes, and good luck :thumbup:
99 VTR1000F Firestorm, a.k.a. The Carbon Express
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Stephan
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Re: Replacing SC36 ICM and converter by an Ignitech DC CDI P

Post by Stephan »

Hi Martin,

Have you found some info for base advance setting? I see you have 15 deg, and your map is approx by 10 deg higher than my with 5 deg, but per my last post regarding it, I still think map values are absolute (plus physical value), so yours is advanced by 10. Unfortunately there was no follow up from ignitech.

http://www.vtr1000.org/phpBB3/viewtopic ... 5&start=75
MK_WF
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Re: Replacing SC36 ICM and converter by an Ignitech DC CDI P

Post by MK_WF »

Thanks folks.

Blipping the throttle automatically would be cool, but it's close to impossible on a carburetor engine. You'd need an EFI system with servo-controlled butterfly valves as a prerequisite.
What you actually can do is to cut ignition in up and downshift when using the right two-way sensor. In my case it's only for upshift.

The ignition map is by no means optimized.
It is based on the supplied map by Ignitech and mixed up with what Stephan and another guy from Germany found.
In addition I reduced the full load and high rpm values a bit to be on the secure side.

The only thing that I have fully verified by measurements is the base advance value of 15 deg. It doesn't not matter that Ignitech did not react on our inquiries.
The algorithm needs a reference point for calculating the timing when to fire. This is the base advance.
It tells the ECU "now the crank is at position X".
If you have a map saying for example "fire at 20 deg", for the ECU it means "fire 5 deg after the 15 deg base advance".

The only culprit with the Ignitech algorithm of map-interpolation is that when the rpm is lower than the lowest rpm column, then it doesn't fire at the map values, but at the base advance.
It's a matter of a stable ignition. If you want to fire "before" base advance (i.e. higher than 15 deg) you need to "wait almost one rotation" and fire the next time you're at the desired position.
This waiting time blurs the accuracy of the timing as a big twin has a rotational nonuniformity that makes the timing jerk. Ignitech compensates this by directly firing at base advance when below lowest rpm value and thus having a "stable" timing.

You can verify that on your own with the help of a strobe.
Unplug the timing plug at the generator cover and strobe the running engine.
At 15 deg BTDC each cylinder has a "F" mark on the rotor that must line up with the case mark.
Set the base advance to 15 deg, set the lowest rpm value to 300 rpm and switch the map to be completely 15 deg (easiest done by using no TPS and setting the remaining curve to constant 15 deg).
The marks on rotor and case match but the timing will "jerk around" a bit. If you rev up, it'll become more stable.
As a second try do the same with a changed first rpm value to let's say 2000 rpm.
Now the idle rpm of 1300 is below that first rpm and the algorithm doesn't not use the "map calculation", but fires at base advance. The marks match and are pretty stable.

Next experiment: Assume someone said the base advance is 5 deg and program that with a first rpm column of 2000 rpm.
When you strobe that, you'll find that the marks match despite the "wrong" base advance value of 5 deg. Why that ? Well, in this case we told the ECU "fire when you get the pick-up pulse" and as we didn't change the mechanical setup on the bike, the timing is still the same (=
right angle).
To confirm that, we now change that first rpm to 300 again and program a map of 15 deg. What we now expect is that it fires at 15 deg, right ? In this case the marks did not line up when strobing it.
The explanation: Now the map values are used and "fire at 15 deg" means "fire 10 deg before the 5 deg base angle". As the physically right base angle unfortunately is 15 deg, it fires 10 deg earlier = at 25 deg = marks don't match.

I did the full procedure from front to end multiple times until the radiator started boiling and came to the conclusion that any base angle values much different from 15 deg are plain wrong.
Slight corrections are ok like in my case I found that with a +1 on one cylinder the marks were closer than with a 0.

So how do you proceed if you have a Ignitech and use a wrong base advance ?
Usually the unit also contains a "wrong" map and both errors negate each other. That means the unit fires at the right physical angles, but the values in the map are not the physical values.
You can correct that on your own by adding/subtracting the difference in base advance to the complete map.
Example: You used a base advance of 5 deg and want to convert the map to a 15 deg base advance. The difference is +10 deg, so change base advance to 15 deg and every map value by +10 deg.
That won't change your physical timing at all, but it makes the values in your map comparable as they now represent the physically used advance angles.
Bye
Martin
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Stephan
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Re: Replacing SC36 ICM and converter by an Ignitech DC CDI P

Post by Stephan »

MK_WF wrote:So how do you proceed if you have a Ignitech and use a wrong base advance ?
Usually the unit also contains a "wrong" map and both errors negate each other. That means the unit fires at the right physical angles, but the values in the map are not the physical values.
You can correct that on your own by adding/subtracting the difference in base advance to the complete map.
Example: You used a base advance of 5 deg and want to convert the map to a 15 deg base advance. The difference is +10 deg, so change base advance to 15 deg and every map value by +10 deg.
That won't change your physical timing at all, but it makes the values in your map comparable as they now represent the physically used advance angles.
Thanks for the great reply.

All in all, will there be any benefit from using correct absolute values in my map, that means I will use 15 deg base and add 10 everywhere?
MK_WF
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Re: Replacing SC36 ICM and converter by an Ignitech DC CDI P

Post by MK_WF »

No. If it's just for riding, you can leave it “as is“.

Just think of it next time you compare maps with other people.
Bye
Martin
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Stephan
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Re: Replacing SC36 ICM and converter by an Ignitech DC CDI P

Post by Stephan »

thanks, it was at least good to point out, someone could miss the fact that values in map are in conjunction with base advance, and ignitech setting is 5.
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