elec tach conversion

I was getting weird noises from my valve cover, pulled it, and found the molded-in tach drive gear on the cam is about 60% chewed up. The gear on the pinion that goes out to the tach cable is ok, and the Tach itself appeared to be working fine...very strange.
Rather than replace the cam, I would like to put an electric tach, that reads off the coil neg wire. I've read that I can use a standard tach and wire it off either of the 2 coils. Has anyone else done this? Does anyone know of a replacement tach that won't be too hard to retrofit cosmetically?

...doin' some more thinkin'..(coupla beers always helps); How about if I buy a new electrical tach, like a "Sun" or something, and replace the original mechanical tach guts with the Sun guts? Plug the pinion hole on the head, and "I be Tackin'"! Think about it..Intriguing, huh?

Put the electrical tach on, you do need to fabricate an adaptor to make it work properly though. Loudhvx came up with an easy to build adaptor that I fab'd and used. You need a resistor and two diodes. Search the archives and you will find the diagram. As for the transfer of parts from the electric to the mechanical housing, you can try it, but it might be easier to fab a mount.

Hey DT, thanks for the info; found it,and gonna print that out. The only reason I wanted to swap guts, was to keep the original look, and have it match the speedo. Plus the original housing is already 'shock mounted'. From what I've been reading, the biggest problem is vibration. I think I'll put a dab of silicone on the needle when I have it all apart. And I plan on using lots of silicone when mounting it inside the housing. Gonna take my time, shop around for just the right tach..

I scored the tach from a Spectre 750 on eBay. It's the same size and will fit the mounting bracket, and it's electric. I'm in the process of tracking down a Spectre wiring diagram so I can figure out which wire does what...

That sounds great. I gotta keep an eye on Ebay. My original tach is just a tach, no idiot lights on it. Yours too? Does your new tach have lights inside it?
As far as plugging the hole in the head, I have a nice solution: I went to my local Ace Hardware, and got what's called a 1/4 20, 3/4"long expansion plug(see attached pic). The thickness of it is 1/2", perfect size for the existing hole. You just add a washer and 1/4 20 bolt, stick it in the hole and tighten it about 1.5 turns. It's like it was made specifically for this repair! I also put back the original screw & clamp that were there, to make sure it doesn't go anywhere.

Post edited by: Wild & KZ Guy, at: 2005/12/02 10:22

guitargeek, you still here?
Did you figure out that tach wiring yet? When you do, could you clue me in? I just bought a Kawi electric tach off Ebay, the wiring is probably about the same.
THANKS!

Wiring a tach for a Vulcan or for a KZ is about the same exercise. Both have two coils so you might find this write up useful:

www.gis.net/~manjo/TACH%20Install.htm

You can get the bit you need from Dynatek and www.z1enterprises.com is a Dynatek dealer.

WG, I'm not sure what model of tach Wild & KZ Guy got for his project, but mine is from a Spectre 750. Johnno posted the Spectre wiring diagram, but his scanner will only do black & white and I need to see the colors to figure out which wire does what.

To further complicate matters, I plan to do the coil wiring mod and install the GPz750 cams at the same time. For now I'm gathering bits and pieces and studying as much as possible before I dive in...

I think the tach mod will work for most any tach...

Check your valve clearances after swapping the cam shafts! Good luck.

Mine is from a Spectre 750 also. I don't actually have mine in my hands yet, it's on the way(from Ebay).
So any wiring diagrams/color codes/help would be very much appreciated. If I get any good info, I'll post it also..

Post edited by: Wild & KZ Guy, at: 2005/12/27 18:27

..just wanted to mention; I have the rest of the instrument cluster, minus Tach, with Volt & TripReset buttons, +160MPH, Fuel, Temp, and idiot lights. As far as I know, it all works fine. I don't need it and will give it to someone who can use it, you just pay the shipping. This is NOT a scam or AD, no bullshit, no additional costs, just trying to help out fellow KZers & make room for beer. There is a crack in the
bottom of the housing that looks like it could be pretty easily glued/fixed. This is off of a 1986 GPZ 600, but I understand it will also fit a 1987 ZX6 Ninja, not sure what else. I have pics and will gladly send if requested. Email me here if interested, just make sure my reply gets thru your spam filters.
By the way, my Tach conversion went extremely well(see pic), had to trim the circuit board here and there, resolder some of it, trim some metal etc. But it came out looking factory, and I even added a pushbutton switch to change from Tach mode to Voltmeter mode. The redline was too high for my KZ650, had to repaint it to 9000.
Safe Riding!

Post edited by: Wild and KZ Guy, at: 2007/01/24 18:05

Post edited by: Wild and KZ Guy, at: 2007/01/25 08:05

Man that looks totally factory. Very nice job!