Help with the Transistored Ignition for motorcycle

[Integer]

Hi!

I have 2 stroke Yamaha TDR 125 which originally comes with CDI ignition. But problem is that my bike have restriction in the CDI which doesn't let him to rev more than 70000 rpm. So I'm decided to build TCI ignition.

I found this schematic:
https://www.rmcybernetics.com/projects/DIY_Devices/homemade_ignition_coil_driver.htm

But I don't know can I reuse my ignition coil, or to buy the new one?

Thanks

 

[crutschow]

The requirements for a CDI ignition coil and and TCI ignition coil can be different so I don't know if it will work. A TCI (Kettering) ignition runs a high current through the primary of the coil whereas a CDI does not. I recommend you buy a coil designed for TCI.

 

[Integer]

Hmm, do you maybe know is there difference between different TCI coils from motorcycle, can I use from any motorcycle which have TCI ignition?

Thanks!

 

[Integer]

I found this DC-CDI, and company that sells is say that it can be used with original coil:
https://www.ignitech.cz/english/aindex.htm

Is there inside this CDI, small coil which produces high voltage(~200V), and then send's it to the original coil to produce 20 kV on spark plug?

 

[crutschow]

A CDI ignition typically uses a DC-DC converter to charge a capacitor (the C in CDI) to ≈200V. A switch, such as an SCR, then suddenly discharges the capacitor into the primary of the coil. This is stepped up by the coil turns ratio to give the high voltage spark output.

 

[Integer]

So, is it simple tu build that kind of CDI, which gets power from battery, than magneto?

I found this schematic, which gets it power from magneto, but is there a way that I can modify this schematic:
https://mastercircuits.blogspot.com/2010/07/yamaha-dt125-cdi.html

 

[crutschow]

Modify it for what? I don't know what your machine has for outputs from the stator.

 

[Integer]

It has PickUP coil!