Tacho? - Page 3 - Motorcycle-Journal Forums

rogerl · 06-28-2009, 01:27 PM

I am having problems with the tachometer. I first wired everything in and fired the bike up and NOTHING. The tach did not read at all. I thought that the resistor/doide bridge was wrong so I checked that and it was built just like the bridge shown in the below web page. I then hooked up one coil wire to the tach lead and the tach works. I then hooked the tach up to the other coil lead and it works there as well. I do not know if the tach is reading 1/2 of was it should be reading or not. I then hooked up the tach thru only one leg of the resistor network at a time and the tach works on both legs of the network and thru both wires if they are hooked up one at a time but NOTHING if both legs are hooked up.
I did a seach in this forum and found a post that showed a diode resistor network that was backwards from the one in the web site below. The schematic in the photo posted by Ray Nielson does not make sense to me. I do not want to try the one in the photo and maybe trash the ignition system. It looks like it could backfeed the other coil.
Any help would be great.

Thanks
Roger L

http://www.motorcycle-journal.com/fo...ght=tachometer

Tachometer Installation

The Dark Knight · 06-28-2009, 03:52 PM

those tachometer installation inst.. look like well... wow.. what is the tachometer that you have come factory set at.. for a 4cyl 6cyl or 8cyl... the boulevard m50 needs a .5pulse per rev... to read right.. so find out whatever resistor would be needed to knock it down to that and hook it only to the white wire on the left side...

rogerl · 06-28-2009, 06:54 PM

Well this even gets better. I had the tachometer hooked up to one of the - coil leads that I pulled into the headlight housing. I decided to take the bike for a ride and see what the tach was reading. I started the bike up and let it warm up a little before taking off. Before the bike went into low idle it stalled and would not start again. I disconnected the tach from the -coil lead and it still would not start. After letting the bike sit for 10 minutes and checking the connections to the coils the bike then started but only after having to crank the throttle. It seemed like the bike was flooded. With the tach disconnected I took the bike for a ride and it ran fine. What is wrong? I bought the tach off E-Bay. Below is the listing for the tach I bought.
Any help would be great.

Thanks
Roger L

Custom Mini Electronic Tachometer Gauge For Harley:eBay Motors (item 140328161006 end time Jun-29-09 11:16:24 PDT)

The Dark Knight · 06-28-2009, 07:54 PM

whats the blue wire for? lighting? looks like red to switched 12 volt.. black to ground.. green to - coil and blue is what... i would think you could get a resistor or something to convert the signal on the green wire down to where it would work..?

rogerl · 06-28-2009, 08:30 PM

The blue wire is for the light. I have the blue wire and the red wire hooked together.

Roger L

The Dark Knight · 06-28-2009, 10:13 PM

k makes sense.. umm... whats it idle at if you just hook the green straight to the white on the left side (opposite the air box)?

PerfectStranger · 06-29-2009, 12:06 AM

Hey, I put that same tach on my Rebel last summer. I had no problems with its performance.

rogerl · 07-05-2009, 05:11 PM

Well i got the tach to work. I used the wiring diagram below and the tach reads the correct RPM. I do not understand why this circuit works but it does.

Roger L

06-28-2009, 01:27 PM	#41 (permalink)
rogerl Clunked into first gear Join Date: Oct 2007 Bike: 2006 Silver M50 Location: Northfield, Ohio Posts: 206	I am having problems with the tachometer. I first wired everything in and fired the bike up and NOTHING. The tach did not read at all. I thought that the resistor/doide bridge was wrong so I checked that and it was built just like the bridge shown in the below web page. I then hooked up one coil wire to the tach lead and the tach works. I then hooked the tach up to the other coil lead and it works there as well. I do not know if the tach is reading 1/2 of was it should be reading or not. I then hooked up the tach thru only one leg of the resistor network at a time and the tach works on both legs of the network and thru both wires if they are hooked up one at a time but NOTHING if both legs are hooked up. I did a seach in this forum and found a post that showed a diode resistor network that was backwards from the one in the web site below. The schematic in the photo posted by Ray Nielson does not make sense to me. I do not want to try the one in the photo and maybe trash the ignition system. It looks like it could backfeed the other coil. Any help would be great. Thanks Roger L http://www.motorcycle-journal.com/fo...ght=tachometer Tachometer Installation Attached Images

06-29-2009, 12:06 AM	#47 (permalink)
PerfectStranger TurtleWax Taster Join Date: Sep 2008 Bike: 2007 M50 Location: North Coast of Ohio Posts: 567	Hey, I put that same tach on my Rebel last summer. I had no problems with its performance. __________________ Geography is where it's at.

07-05-2009, 05:11 PM	#48 (permalink)
rogerl Clunked into first gear Join Date: Oct 2007 Bike: 2006 Silver M50 Location: Northfield, Ohio Posts: 206	Well i got the tach to work. I used the wiring diagram below and the tach reads the correct RPM. I do not understand why this circuit works but it does. Roger L Attached Images

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06-28-2009, 03:52 PM	#42 (permalink)
The Dark Knight TurtleWax Taster Join Date: Jul 2008 Bike: Suzuki Boulevard M50 Location: Central Oklahoma Posts: 572	those tachometer installation inst.. look like well... wow.. what is the tachometer that you have come factory set at.. for a 4cyl 6cyl or 8cyl... the boulevard m50 needs a .5pulse per rev... to read right.. so find out whatever resistor would be needed to knock it down to that and hook it only to the white wire on the left side...

06-28-2009, 06:54 PM	#43 (permalink)
rogerl Clunked into first gear Join Date: Oct 2007 Bike: 2006 Silver M50 Location: Northfield, Ohio Posts: 206	Well this even gets better. I had the tachometer hooked up to one of the - coil leads that I pulled into the headlight housing. I decided to take the bike for a ride and see what the tach was reading. I started the bike up and let it warm up a little before taking off. Before the bike went into low idle it stalled and would not start again. I disconnected the tach from the -coil lead and it still would not start. After letting the bike sit for 10 minutes and checking the connections to the coils the bike then started but only after having to crank the throttle. It seemed like the bike was flooded. With the tach disconnected I took the bike for a ride and it ran fine. What is wrong? I bought the tach off E-Bay. Below is the listing for the tach I bought. Any help would be great. Thanks Roger L Custom Mini Electronic Tachometer Gauge For Harley:eBay Motors (item 140328161006 end time Jun-29-09 11:16:24 PDT)

06-28-2009, 07:54 PM	#44 (permalink)
The Dark Knight TurtleWax Taster Join Date: Jul 2008 Bike: Suzuki Boulevard M50 Location: Central Oklahoma Posts: 572	whats the blue wire for? lighting? looks like red to switched 12 volt.. black to ground.. green to - coil and blue is what... i would think you could get a resistor or something to convert the signal on the green wire down to where it would work..?

06-28-2009, 08:30 PM	#45 (permalink)
rogerl Clunked into first gear Join Date: Oct 2007 Bike: 2006 Silver M50 Location: Northfield, Ohio Posts: 206	The blue wire is for the light. I have the blue wire and the red wire hooked together. Roger L

06-28-2009, 10:13 PM	#46 (permalink)
The Dark Knight TurtleWax Taster Join Date: Jul 2008 Bike: Suzuki Boulevard M50 Location: Central Oklahoma Posts: 572	k makes sense.. umm... whats it idle at if you just hook the green straight to the white on the left side (opposite the air box)?

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