Help please

[05BDMchopper]

I have a 05 BDM Chopper , New 120 Ultima installed ... My question's are
Where does the Tach wire (green) connect ?
Being now no mechanical crank position sensor used . Do these hook together ?

 

[Rottweiler]

The green wire should be the input to the EHC from the Ignition module. Output to the tach is yellow.
here is a link to wiring Dia.

Dropbox

www.dropbox.com

 

[Mikeinjersey]

I have a 05 BDM Chopper , New 120 Ultima installed ... My question's are
Where does the Tach wire (green) connect ?
Being now no mechanical crank position sensor used . Do these hook together ?

What Rottweiler said is true but If you are changing from a system using a Crank Position Sensor to a system with a Cam Sensor the ignition module is different. Also the Ehc will be different and the connectors to ehc from the ignition modules will be different. The tachometer signal is not a function of the EHC so the signal wire (green) from the ignition module can probably be connected directly to the (yellow) tach input wire , bypassing the EHC if necessary.
Also Timing is different for the CPS system vs Cam Sensor system. CPS system has timing and dwell set at the factory and the Cam sensor system needs to be adjusted manually.
Disclaimer: I do not have personal experience doing what I suggested. Before cutting any wires please wait for verification from others on this site. I would hate to cause you any problems.

 

[Th3InfamousI]

I have a 05 BDM Chopper , New 120 Ultima installed ... My question's are
Where does the Tach wire (green) connect ?
Being now no mechanical crank position sensor used . Do these hook together ?

I am guessing the Ultima has a cam sensor in it that's usually what they would come with. Make sure you set the cam sensor to single fire, unless did you change your coil?

Basically you will be able to eliminate some wiring and that thunder heart box now. Can you confirm what ignition setup you are running now in the nose cone & what coil you are planning to run? Be easier that way than giving you information that isn't a match for what you got.

 

[05BDMchopper]

I am guessing the Ultima has a cam sensor in it that's usually what they would come with. Make sure you set the cam sensor to single fire, unless did you change your coil?

Basically you will be able to eliminate some wiring and that thunder heart box now. Can you confirm what ignition setup you are running now in the nose cone & what coil you are planning to run? Be easier that way than giving you information that isn't a match for what you got.

I'm using the original big dog ignition (single fire )

 

[05BDMchopper]

If the green tach wire is not connected ...
How does the computer run the RPM ?
How do I convert this so it works ?

 

[Mikeinjersey]

If the green tach wire is not connected ...
How does the computer run the RPM ?
How do I convert this so it works ?

Your best bet is to contact https://www.bigdogpartskingpin.com/ or https://www.wildsteedworx.com/ They will know what you will need to make your system work. I doubt there is a way to connect a single-fire cam sensor to your original ignition but if there is a way those guys will head you in the right direction. Be sure to let us know what you end up doing. Good Luck

 

[05BDMchopper]

Your best bet is to contact https://www.bigdogpartskingpin.com/ or https://www.wildsteedworx.com/ They will know what you will need to make your system work. I doubt there is a way to connect a single-fire cam sensor to your original ignition but if there is a way those guys will head you in the right direction. Be sure to let us know what you end up doing. Good Luck

Thanks , I've gotten some parts from wild steed works before and they were smart people

 

[Th3InfamousI]

If the green tach wire is not connected ...
How does the computer run the RPM ?
How do I convert this so it works ?

tach works off the ignition module

Green is tach on your new unit it will be connected to the green wire going into the Thunder Heart box.

_________________________________________________

Green to Green - (Going into Thunder Heart Box)
Blue to Yellow (Leaving Thunder Heart Box) - Front Cylinder
Pink to Blue (Leaving Thunder Heart Box) - Rear Cylinder

Red coming into the box your best bet is to to crimp it to both White on the Ultima Ignition & Red on the wire leaving the thunder Heart box to power your coil & ignition module when you turn on the key & hit the run button to keep it same as stock.

Violet you won't use just cut and heat shrink wherever.

 

[05BDMchopper]

tach works off the ignition module

Green is tach on your new unit it will be connected to the green wire going into the Thunder Heart box.

_________________________________________________

Green to Green - (Going into Thunder Heart Box)
Blue to Yellow (Leaving Thunder Heart Box) - Front Cylinder
Pink to Blue (Leaving Thunder Heart Box) - Rear Cylinder

Red coming into the box your best bet is to to crimp it to both White on the Ultima Ignition & Red on the wire leaving the thunder Heart box to power your coil & ignition module when you turn on the key & hit the run button to keep it same as stock.

Violet you won't use just cut and heat shrink wherever.



I see the green (tach) wire out of the ignition module on the wire diagram , I'm just trying to get this all figured out before I go splice and wires and f****** something up, this is my idea of the green wire to this green wire but didn't know if the ignition module generated this signal or if we could patch it in after the ignition module , or if it was the same being now it's off the cam instead of the crank position sensor
View attachment 82462

 

[05BDMchopper]

I see in this diagram the green wire coming out of the ignition module , can I just connect the green wires or does this need to generate the RPM off of the front and rear cylinder coming into this ignition module

 

[05BDMchopper]

Or is there a chance that I can connect it to the old crank position wires going into the ignition module ?

 

[Th3InfamousI]

I see in this diagram the green wire coming out of the ignition module , can I just connect the green wires or does this need to generate the RPM off of the front and rear cylinder coming into this ignition module

Green to green that's it...

RPM comes out of that ultima ignition now straight to tach

Sent from my moto z4 using Tapatalk

 

[05BDMchopper]

talk to the guys at wild Steed works gives me the answer of take the ignition module completely out and hook the green wire to the green wire and it'll work

 

[05BDMchopper]

You remove the ignition module completely hooking the green tack wire coming from the Ultima motor to the green tack input wire to the computer it's the same signal

 

[Mikeinjersey]

You remove the ignition module completely hooking the green tack wire coming from the Ultima motor to the green tack input wire to the computer it's the same signal

Yes , Now you still need to supply 12 vdc to the New Ultima Ign system and the coil like TH3Infamous pointed out. Also the front and rear signal wires from the module need to be connected.

 

[05BDMchopper]

Yes , Now you still need to supply 12 vdc to the New Ultima Ign system and the coil like TH3Infamous pointed out. Also the front and rear signal wires from the module need to be connected.

These connections are made , thanks again everyone