Hour meter on Chinese engine?

[wheelbender6]

Has anybody used an hour meter on their bike engine? Most meters I have found will not work on a magneto fired engine without a battery. They need a 6 or 12 volt lead.

My current speedometer/odometer is a bicycle computer and you must remember to push the start button before each ride to activate the odometer function.
Cheers

[Dave31]

check this thread........http://motorbicycling.com/f3/tach-1627.html

It's a tach with hour meter

[spad4me]

There is also tiny tach which can be had with a resetable indicator.
YOU CAN NOT REPLACE THE BATTERIES IN THE TINY TACH BUMMER!
Tiny-Tach: Gasoline Tachometers

2cycle and 4 cycle 1 or 2 cylinder.

[gerichardson]

I tried one that is similar to the Tiny Tach. It worked but I had some problems.

The one I tried is an ENMCO PT15E26. There is a problem with the inductive tachometer / hours meter. I purchased two and the first installation worked great for awhile, but it would go crazy at high rpm, such as over 6,000rpm.

Sometimes it would go blank and then restart or else I would get a message “SERVICE”. It would happen randomly. These are sealed units and there are no buttons to reset unlike some. The problem may be due to RF generation from the AC voltage of the magneto, inducing current in the leads.

Initially I replaced the first unit thinking it was defective but the same problem occurred. Then after a fast ride the entire screen went blank and would not show hours. I reconnected the first one and tried to route the wires away from the sparkplug wire and CDI but it also failed the same way.
I don't have any problem with my bicycle speedo/computer it works fine.

What did I do next? What any good MB'er would do.... I dissected the unit to see if I could fix it.

The epoxy inside the back of the unit was soft and pliable and easily removed with an exacto knife and toothpick to expose the battery. The battery was a standard 3volt lithium 2032.

On the circuit board were two pads that said reset. So I shorted across them and the display performed some sort of count down with the hours symbol, the words CHG, RPM and SERVICE illuminated it looked like random numbers changing. Then it went to the display with the hours symbol and 0.0. I thought that did the trick but after a few seconds the screen went blank.

Not knowing if it was low battery voltage, I soldered on a connection to a AAA battery pack and connected a couple good batteries so that I knew there was 3 volts. This ended in the same result.

Maybe something is damaged in a chip where it listens for spark pulse? Anyone else have any ideas?

--George

[Biker Mike]

Looks like a warranty exchange is out of the question for that one. Sorry for your loss...LOL

[gerichardson]

Just like the Chinese I think that I have reversed engineered this device.

I was looking on the little circuit board in the back of the meter and saw another pad. It seemed to be in a similar position to where the reset buttons are on the other styles of meters..

In reading some of the literature on the manufacturers website, I found the resetting procedure and what to hold down for how many seconds.

I figured this board must still have some similar behaviors. So I tried shorting the pad to one of the reset pads with a bent paperclip and VOILA!

I now have a display.

I'm going to reinstall with some shielding on the leads, maybe some coax.

Here are some pictures if anyone else needs this info.

--George