96 T'Bird Tach Gone Crazy

[Jerrydef]

Hopefully someone can give me some advice to WHY the Tach on my 96 T'Bird Cruiser will work fine, then just go to -0- and stay there for a few minutes, then work again, then sometimes goes to about 5000 RPM regardless of the true RPM and just stay there while the engine is running, then drop back to -0- and so on.

Is the Tach shot? If so who repairs them in USA? Is it a bad Connection somewhere; or a bad (corroded) Ground? All thoughts will be helpful.

Thanks

 

[grandpaul]

Sounds like a loose connection.

I'm moving your thread to a more appropriate forum section.

 

[Mad On Triumphs]

Hopefully someone can give me some advice to WHY the Tach on my 96 T'Bird Cruiser will work fine, then just go to -0- and stay there for a few minutes, then work again, then sometimes goes to about 5000 RPM regardless of the true RPM and just stay there while the engine is running, then drop back to -0- and so on.

Is the Tach shot? If so who repairs them in USA? Is it a bad Connection somewhere; or a bad (corroded) Ground? All thoughts will be helpful.

Thanks

Hi Jerrydef,
I posted this a few months ago, and to date my rev counter is 100% perfect. I do hope that this helps you out.
Good Luck




[h=2]Erratic Rev Counter Thunderbird 900[/h]

I have for sometime now been plagued by an erratic rev counter, I have today cured my problem with a small bit of wood. Let me explain.
I dissembled the Taco as much as you can, and sprayed WD 40 onto the back of the rev counter, ( Through the 2 holes where the little bulbs go. be careful not to go too mad and spray the underside of the glass ) also spraying the 3 pin connector that goes into the taco it'self. I reconnected the 3 pin connector to the rev counter. I then started the bike up before putting the assembly all back together, but to my dismay it was still the same, erratic, and not even registering whilst at idol speed. It was while I was fiddling about with the connection it'self that the rev counter decided to work perfectly. Now I'm no Einstein but the problem seemed to be this connection. So messing about with this connection more than a few times, brought the same result. Working not working, so it was obviously a loose connection. So I cut a very small piece of wood and tapered one end, and carefully wedged it between the 3 pin connector and the rev counter housing. I'm pleased to say that it has now cured my erratic rev counter problem, and is even registering when the bike is at idol, something it's not done for a while now.
I understand that this is more than likely not in the Triumph workshop manual, but it's just saved me £200.
My bike is a 1995 Thunderbird ( Not the sport ).
Hope that this helps someone out there​

 

[The Seeker]

Sounds like a toothpick may have worked just the same...or bending the three pins slightly so they make better contact.

 

[Mad On Triumphs]

I thought about bending the pins, but knowing my luck 1 would have snapped off, so I took the cowards way out. I dare say tooth picks would work just as well though. Can't beat a bit of improvisation, ( I think that's a posh word for bodge up :y24: ) especially when you save a few bob ( Whoever Bob is )

 

[keystiger]

Round these parts its called "Redneck Engineering" (I have a PHD in R.E. and am working on my Masters Thesis in Duct Tape specialization) and looks as though you are working on your Doctorate there Mad
Good on ya.

Hope it helps Jerrydef.

 

[Mad On Triumphs]

As you're aware a few years ago I had some trouble with my 1995 Thunderbird 900 rev counter, the problem being that it was erratic, and wouldn't respond to the throttle.
It would sometimes work then it wouldn't, well I fixed this by jamming a bit of wood at the side of the 3 pin connector, which up till the end of last year had worked a treat. Well at the end of last year it finally died, and no matter what I did to the tacho connections it just would not work. So I contacted my local Triumph dealer to buy a new tacho, it was then that they told me that you could no longer buy the tacho on its own, but you could buy the tacho complete with a new speedometer ( which I didn't want or need ) for a bargain price of just £600, You're having a laugh springs to mind.
There was no way that I was going to pay that, that in my opinion was, and is, a rip off.
So I decided to try and fix this tacho on my own, it was then that I remembered some advice here, that at the time I was unwilling to do, and that was to bend the 3 pins that are at the base of the tacho, that the 3 pin connector, connects too.
If you have a problem with your tacho which I have described Do Not Bend The Pins. I bent the pins and then tried to reconnect the connector to the 3 pins, to re-establish a good connection, and promptly pushed the 3 pins back into the tacho. Now the taco was useless as I couldn't get anything on the pins to pull them out. So I decided to drill a hole in the side of the casing and push the pins out again, and then reconnect the 3 pin connector, then seal the hole up. This I did, but it still wouldn't work.
So I searched the Internet and came up with this chap Classic and Modern Motorcycle Speedo Repairs - Home now I'll grant you he's not cheap, but I thought that as this chap upgrades to aircraft components, it would hopefully last a long time ( Touch wood ).
Well I sent it away and 3 weeks later it came back, there was a slight problem as the revs at idle were registering 2200 rpm which as we all know is way to high, so I contacted the chap Peter and he said send it back as he had an idea as to what might have happened.
Well yesterday it came back and the problem was that the pointer had moved ( ? ) so I reconnected everything and just hoped that everything would be ok this time, and I'm pleased to say that at this moment in time all's well. It now indicates the correct idle speed, and responds to throttle input as it should.
His work comes with a years guarantee, which I hope that I won't have to call on anytime soon.

 

[Terrypsmith]

As you're aware a few years ago I had some trouble with my 1995 Thunderbird 900 rev counter, the problem being that it was erratic, and wouldn't respond to the throttle.
It would sometimes work then it wouldn't, well I fixed this by jamming a bit of wood at the side of the 3 pin connector, which up till the end of last year had worked a treat. Well at the end of last year it finally died, and no matter what I did to the tacho connections it just would not work. So I contacted my local Triumph dealer to buy a new tacho, it was then that they told me that you could no longer buy the tacho on its own, but you could buy the tacho complete with a new speedometer ( which I didn't want or need ) for a bargain price of just £600, You're having a laugh springs to mind.
There was no way that I was going to pay that, that in my opinion was, and is, a rip off.
So I decided to try and fix this tacho on my own, it was then that I remembered some advice here, that at the time I was unwilling to do, and that was to bend the 3 pins that are at the base of the tacho, that the 3 pin connector, connects too.
If you have a problem with your tacho which I have described Do Not Bend The Pins. I bent the pins and then tried to reconnect the connector to the 3 pins, to re-establish a good connection, and promptly pushed the 3 pins back into the tacho. Now the taco was useless as I couldn't get anything on the pins to pull them out. So I decided to drill a hole in the side of the casing and push the pins out again, and then reconnect the 3 pin connector, then seal the hole up. This I did, but it still wouldn't work.
So I searched the Internet and came up with this chap Classic and Modern Motorcycle Speedo Repairs - Home now I'll grant you he's not cheap, but I thought that as this chap upgrades to aircraft components, it would hopefully last a long time ( Touch wood ).
Well I sent it away and 3 weeks later it came back, there was a slight problem as the revs at idle were registering 2200 rpm which as we all know is way to high, so I contacted the chap Peter and he said send it back as he had an idea as to what might have happened.
Well yesterday it came back and the problem was that the pointer had moved ( ? ) so I reconnected everything and just hoped that everything would be ok this time, and I'm pleased to say that at this moment in time all's well. It now indicates the correct idle speed, and responds to throttle input as it should.
His work comes with a years guarantee, which I hope that I won't have to call on anytime soon.

What sort of money did he charge to return the tacho? Mine doesnt work either I was thinking it may be the ignitor has I have a Miss fire as well.

 

[Qship]

The member Mad on Triumphs hasn't been on here since end Oct, so you may get an answer soon.........maybe not. He does not frequent here much anymore.

 

[Terrypsmith]

What sort of money did he charge to return the tacho? Mine doesnt work either I was thinking it may be the ignitor has I have a Miss fire as well.

I've sorted my tacho issue out. Yippie. The issue was with the connection from the plastic connector on the tacho to the internal circuit board. My tacho is one of the earlier ones 1996 where there's a white female 3 pin connector on the back of the tacho. Obviously a white male connector fits in this. The issue is the female connector pins pass through holes in the circuit board and are soldered. Pulling the male connector out loosened one of the pins creating a inconsistent connection. I.e. it works and then doesn't. The connector on the loom has 3 wires one is a live feed, one is a earth and the other the middle one (but check your wiring diagram) runs to the ignitor. With the bike running and the male connector disconnected I check continuity to earth on the earth wire, all ok, a 12v power feed on the live, all ok and a power signal coming off the ignitor wire it was about 10volts at idle when the bike is revved up the voltage increases. This told me that the loom was functioning ok and the issue was with the tacho.
To get to the circuit board is a real pain. First you have to prise up the the edge of the chrome clock surround to remove it. Take it slow. Once the surround is removed, the rubber seal and glass comes with it, you can then remove the needle and tacho dial face, two small screws. At the back there are 3 brass insert screws remove these, be careful as they hold the motor to the board and once released it falls out. Once you have the board out you will see where the connector pins pass through the board. On the rear of the board you will see the circuit tracks, I checked for continuity from each pin to a connection point on the track. In my case one pin was loose so I resolded it and reassembled less the glass, seal and chrome rim. Once fitted to the bike with the ignition on but not running the needle re zeroed so I removed it, a push fit, and set it to zero before starting the bike. Once started, aye presto, the tacho worked. It was just a case of removing again and refitting the glass seal and chrome rim. When fitting the chrome rim you need to apply a little pressure to the back of the tacho to compress the seal and carefully bend/tap the the edge back to make a tight fit. take it slow and its achievable, just to be 100% sure I run a small bead of silicone around the edge so I had a water tight seal. Hope this helps someone. I took this approach because I couldn't source a replacement.