CONFUSED about CDI vs TCI and What's On Your Virago? [INFO.]

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ViragoJoe
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CONFUSED about CDI vs TCI and What's On Your Virago? [INFO.]

Post by ViragoJoe » Tue Feb 23, 2021 8:15 am

Are you confused about CDI (Capacitive Discharge Ignition) vs TCI (Transistor Controlled Ignition) and what "Ignition System" is really on your Virago?


With Mace_Hacker's assistance and inputs, I think we have solved that riddle, with the following information gathered from the Internet. It has been determined that Virago’s are TCI Only Ignition Systems.

First:
How Spark Is Made CDI vs TCI:
https://www.sportdevices.com/rpm_readin ... nd_TCI.htm

Click Image to Enlarge:

SCR - (Silicon Controlled Rectifier).
IGBT - (Insulated Gate Bipolar Transistor).
HOW SPARK IS MADE - CDI and TCI 2.png
Note in the above comparisons. The CDI system has a coil that is LESS (<) than ONE OHM.
Where as the TCI system coil is GREATER (>) than ONE OHM.

I've found more information on the functionality of the CDI vs TCI Igniters (Brain Boxes) and it is a very good explanation. See below:

"TCI collapses an already charged coil by disconnecting it (TCI switches off briefly). These systems generally use a higher resistance type coil and are known as an "induction" or "Kettering" ignition systems.

CDI sends a brief high (200+) voltage pulse to an uncharged coil which act like a transformer and multiplies it even higher. The step up is normally around 100:1. These systems tend to use low resistance or "racing" coils.

CDI modules normally use low resistance type coils. Remember that CDI is "shooting" a voltage pulse through the coil. TCI (or induction ignitions) use (and expect) higher resistance "induction" type coils. Remember current is flowing through the TCI to the induction coils continuously and the coil is fired when the TCI shuts it off."
So, the 'TCI is a “break” technology, and the CDI is a “make” technology.'

Also, the CDI box has a shorter duration spark to the Spark Plugs and the TCI has a longer duration spark that improves upon the combustion process.

Found the coils specifications in the Clymer's manual page 188 below:

The coils are all above (>) ONE OHM on the primary winding and confirms, Virago's are all TCI Ignition Systems.
Here are the Specifications of the coils by model years.
Click Image to Enlarge:
ELECTRICAL SPECIFICATIONS from CLYMERS MANUAL.png

Virago Igniter Boxes by part number, model, and year:
Click Image to Enlarge:
CDI - TCI IGN BOXES BY VIRAGO MODEL AND YEAR.png
The Virago family were all TCI equipped with varying components from model year to model year.

Hopefully, this research has resolved and corrected any confusion of the type of Ignition system that are on our Virago's.
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ViragoJoe 🇺🇸
1996 XV1100SH Virago Special
"Never ride faster than your Guardian Angel can fly!!"
;)


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Yamaha Virago manuals for download. Left Side Panel
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1992 Virago 1100

Re: CONFUSED about CDI vs TCI and What's On Your Virago? [INFO.]

Post by Mace_Hacker » Wed Mar 17, 2021 3:33 pm

Joe,
Good post. It does clear things up a bit.


Mace
Don't worry; It's supposed to sound like that.

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ViragoJoe
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Re: CONFUSED about CDI vs TCI and What's On Your Virago? [INFO.]

Post by ViragoJoe » Wed Oct 20, 2021 7:33 am

IMPORTANT TO KNOW!!

Click Image to Enlarge:
TCI IS NOT CDI.png
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ViragoJoe 🇺🇸
1996 XV1100SH Virago Special
"Never ride faster than your Guardian Angel can fly!!"
;)


NOTE TO ALL:
:arrow: Please edit your profile with location (State/Country) & Bike Information. It will aid us in assisting you!


Also: If this website was helpful, please consider donating to help keep this site here for yourself and future Virago owners.

Yamaha Virago manuals for download. Left Side Panel
or Click this Link:
https://viragohelp.com/phpbb3/viewtopic.php?f=64&t=1722

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