What's up Doc,

I just removed the capacitor and joined the wires together and is worked fine. So basically all I have is the resister tapping into the line off the ground.

I did the stick coil mod on my F3 also, my only concern with the mod is that the suction cup that go over the spark plug holes are no longer there after the mod is done. I worry if I get caught in heavy rain that water could end up going into the plug holes and possibly getting into the engine. I know there is drainage in the hole just in case of such an event but I'd rather not get any water in there. Did you do anything to combat this worry I have?

 

OK, so it seems that the resistor load is all you needed to get the signal clean for the tach. Good info to add to the database. Users may have to try both approaches (cap and resistor, resistor only) on a case by case basis. I don't recall if I tried only the resistor myself. I may be doing some more wiring work soon, and if it looks easy enough I may try eliminating the capacitor on my setup to see if it still works.

I talked a bit with my senior tech who also rides before I put in the stick coils. We both kinda figured that the scenario of water getting into the cylinder after sitting in the plug well of a head that is probably hot enough to boil water when running, and then through a threaded connection that is gas tight to 150 or more psi is probably kind of a non-issue. There might be a more likely issue of corrosion at the coil socket/spark plug interface if the well fills with water that just stands there. But a hot engine is probably gonna make that standing water evaporate pretty fast. I'm kind of a fair weather rider and keep the bikes garaged, so I just left it as-is.

 

I might have an answer for this.

When I was connecting my koso gauge to the Triumph I ran into a weird issue: when I gave it revs all the tach did was vibrate a little, and the digital SPEEDO was actually reading the revs showing speeds of over 300km/h. What fixed the issue was when this one tech wiz at the Triumphrat forum told me to fit a 4,7kOhm resistor between the switched 12v and the tach signal wire. Why? Because the sensor that reads the revs is essentially an open collector transistor so it needs to be energized from outside. The T595 or mk1 Daytona had the resistor physically fitted into the wiring harness, on the 955i or mk2, the resistor is embedded into the gauge circuit board, which I suspect is the case here too. Without external energizing all the rev sensor is is basically a self revolving door with no one going through, so tapping into the ground wire probably gives the sensor enough juice to produce a readable pulse for the gauge, which probably doesn't have a powered tach wire as does not the koso either, or since you were getting SOME readings out there might be power in the wire but not enough for the higher revs.

Hope I'm making any sense here

 

I think it might be the same type of thing but a slightly different situation. I say this because what you are describing is "pulling up", giving the tach pulse signal a minimum voltage of 12V by putting a +12V bias on it. Sabotage has actually pulled the tach signal minimum voltage to 0 volts. My hunch is the resistor load to ground also reduced the size of the pulse somewhat. I think what may be going on in my and Sabotage's case is the signal needed some cleaning up - and it may also be that the tach signal on our bikes is inverted relative to the tach pulse signal on the Triumph.

That's why I was using a scope to suss this stuff out. It helps to be able to see what that tach pulse is really doing.

 

Doc, i tried both methods with and without the cap neither would work so i decided to tap the wire coming from the ECU to see if it was a wiring issue up front it still didnt work BUT, while i had everything hooked up i put a test light on the wire coming from the ECU just to see if it was getting the voltage pulse and the Tach works perfectly. When i removed the tester the Tach stopped working. Any ideas? im about ready to give up on this cluster.(this was while both the cap and resistor were still connected up front on the tach input)

 

Presumably you had the test light leads connected across the signal wire and ground. Sounds like the tester was creating a ground reference. If you have that resistor on the tach side of the cap, try moving it to the ECU side of the cap. If that doesn't work try a smaller value resistor.

 

how much smaller resistor you think? i tried a 680 and the tach would read but way way high like 9000 at idle. maybe 20,000 ohm? i hate to keep buying resistors on ebay by the 10 packs when im not sure if they work, is there any way i can fashion some type of a variable resistor then adjust it were the tach works right then put a meter on it to see what ohm i need to buy?

 

Doc, i checked the stock Tach that came off the bike granted it has 2 wires that goto the Tach but between those 2 wires its showing 50k Resistance , safe bet on 50K resistor to put in instead of the 100k? (as you suggested i changed the position of the resistor but made no difference)

 

here is some pics to show you the stock tach if it helpsThis is were i tested and got the 50K from right at the terminals in the tach.



This is the little board that connects to the tach from the ecu wire(this was inside the old cluster)


Just an overall shot to show you how it all hooked up the 2 posts on the board was were a ground and the ecu wire bolted onto the cluster

 

Unfortunately I don't imagine the value of the resistor in the stock tach driver has much relation to what the SS182 might need. You could wire up a potentiometer, say 50Kohms, as a variable resistor by jumpering the center terminal to one of the end terminals. Put that in in place of the resistor and vary the setting. Then just measure the value across the end terminals of the pot when you get a stable reading at all rpms, and sub in a fixed resistor of more or less the same value. Also remember that you can parallel resistors to get a lower value, for example two 50K resistors in parallel make a 25K resistor, four in parallel make a 12.5K resistor.

FWIW the SS182 in my HuRRicane is still working very well after several months. The bike is well sorted and is now for sale.