Tacho cutting out at 7000

[Lachie04]

Hello Chaps,

I have just fitted a dyna 2000 to my 7fiddy K engine (yeah I know there's  probably better ignition systems) however as the title says 

Have the dual picks dyna 3hm green coils and taylor leads all seems to run very well, the rev limiter is set to 11500 

and connected the yellow wire to the tac input (First I somehow though it was the green following the instructions but that was reading double so changed over to the yellow)

Anyhow when it hits 7000 the tacho cuts out,  

Has anyone experienced this as I am a bit stumped on what it could be as everything is working well apart from that

 

Edited September 29, 2018 by Lachie04
added detail

[Lachie04]

it seems like the signal cuts out from the dyna so I might check with them about that

l was thinking maybe could get the signal from the - side of the coil

its a oem tacho which normally gets signal from the ECU has anyone ever connected the oem tacho in this manner would it work?

 

[no class]

.....hmmmm....I remember the tach wire being black with red tracer

[Lachie04]

Sorted

Don't know why Dyna signal is cutting out at 7000 every thing is working fine apart from that

Anyhow I wired up a spare tacho to the " - " output from the 1-4 coil and it didn't blow up anything so permanently wired the input wire to the tacho to the coil and works ok

[Gixer1460]

7 hours ago, no class said:

.....hmmmm....I remember the tach wire being black with red tracer

Its the tach wire from the Dyna that is yellow which then connects to the OEM tach wire Black/red (for clarification).