RPM signal issues

Shawn Patrick

Building a pro street gen 1 busa and having issues with stock gsxr 1000 tach not reading signal(Microtech not reading rpm either) yet tach cycles when key turned on and TIC reads signal fine which is tied into rpm wire from ecu...Im thinking possibly ecu is wrong one? Not sure what year bike is but it is a gen 1
You have a problem. There were 3 ECU's used for Gen I's

Tell me the year,look at the frame or yer regi papers.

99-2000 used the same
2001 used the same one
2002 on used the same one.

early ones 16 bit,later ones 32 bit

If the ECU is the wrong one, the bike wouldn't run.

Are you saying you have an NLR TIC, a Microtech, and a stock 1K tach all tied into the same tacho output from the ecu?

Try removing the TIC and Microtech and see if the others get the signal. You can also try putting an oscilloscope on it to see what you are dealing with.

What exactly are you trying to do with the bike?
why not give the Microtech the signal off of coil 1? i had some issues when i tried to tie more than 2 devices off of the RPM signal wire.