Tach Help!!

[geniusloerts]

ok, so i am trying to hook up a after market tach to my bike and it says to connect it it the wire that comes from the stator to the coil.....on our bike there are 2 wires that go to the coils a red with white stripe and a orange.......

Which is correct.....according to my book the orange goes the the Ig. Unit and the Red and white does tooo.???????? hmmmmm


where to go?

[geniusloerts]

it seems that the red with white is a hot wire when ever the key is on.....does this sound right?

that would make the orange and the other......gray or white...which ever it is........teh ones that send the spark signal

[TopCatGr58]

That's right,

The Orange or Gray wires are the trigger wires, you can use EITHER one, but NOT BOTH together!! And I think you set the tach to 2 cylinder mode! Good Luck!
T.C.

[DavesXS]

Yes just like TC stated with the wires, and you do set it for 2 cylinder models. V twin tach is what I am using.

[geniusloerts]

2nd try

ok, well i already typed this out, but it didnt post.....hrmmm


ok so the tach i am using says to hook it to the wire from the stator to the coil. the tach is a computer unit, in it you can set it for the number of pulses per rev. the options are 0.5, 1, and 2. you choose one of those and go. also it has the option to put in a rpm where the motor may change its number of pulses per rev. this way it will account for it.

the other option is to wrap the wire around one of the spark wires (5 times to start, then increase wraps or decrease to hone in the tach) i thought this was kins hokey.

the tach unit i am trying to use is the "Vapor" from trail tech, I got the speedo working, the temp sensor and the other things, the tach is giving me some grief

so i have it set up on the orange wire to the coil, and 2 pulses per rev. but for some reason my rpms fluxuate about 400rpm, and when i get to "3600"ish rpm it suddenly drops to "2200" ish rpm........hmmmm

[danteinien]

I also have the Vapor computer.

The Tach is also giving me some grief, the best reading I could get was just placing the pickup wire on one of the spark plug wires, barely touching it, just the end on the wire, no wrapping. And also, I made sure the wire was far away from any other spark plug wires.
I think with our bike's wasted spark and all the wires so close to eachother, the pickup picks up a lot of disturbance. I'm still experimenting some other things, I'll let ya know what I find out.

[geniusloerts]

same here

[DavesXS]

Set it for 2 fires per rev.

The signal wire "must" go to the neg side of one coil, as described by TopCat.
If you attach it to the stator signal it will count 4 fires per rev, and the volts will be low at idle and the tach might not read untill you give it gas(I know because I did this)

[danteinien]

OK, after trying many things, I got it!

Ok, hooking it up to one of the coils, orange or grey doesn't matter, the tach was reallly jumpy and inaccurate, so i decided to go further back into the harness. I tried both of those wires right where they go in/out of the Ignition Module, same problem. Now, there is a wire coming out of that same plug on the Ignition module, I can't remember but I beleive it was black with a white stripe. It was on the 'top' of the plug, on the far right if your looking at the front of the module, on the left plug(the bigger one)
I shoved my red pickup wire in with that one and vuala, perfect tach signal. I don't remeber what setting I had the tach on, .5, 1 or 2. I'll let ya know and take of pic of what I'm taking about later today!

[danteinien]

Here ya go

You can see it's a Black wire with a White stripe, I just exposed some of the wire and shoved it in the hole with the black wire, and vuala, pefect working tach.

[3Phase]

The Black/White wire is for the emergency ignition cutoff tipover switch. It grounds that wire to kill the ignition.

If you tip over the bike your tach won't work.


If you get strange ignition problems, disconnect the tach.


Regards,

Scott

[DavesXS]

Your getting 4 fire per rev on that wire. Grounding the neg side of the ignition is how you add a kill switch. Or tip switch kill.
You have your tach set for a 4 cyl. Thats why it looked jumpy on just one coil. Now your getting the signal when both coils fire.

You could be riding down the road and suddenly kill ignition with tach hooked to the same wire as a kill switch. But what ever works right?

[danteinien]

Well, I tried the negative side of the coil, on all the settings on the tach, could never get it to read without jumping up and down, sometimes even like 1200 rpm! It was real frustrating, and using that kill sith wire worked great, if it causes issues, i've been driving it for two days now without incident, then I'll unhook it.

But you can't beat a steady tach! And yup, whatever works right?

[geniusloerts]

danteinien,

so what setting did you end up putting it on? the .5, 1, 0r 2? you should be acle to click through the settings and see without changing anything.

[danteinien]

I'll check when I get home, I forgot to check