ET: Engine (Twin) Electronic Rev Counter

[erik]

I went the machanically way with the rev counter.It is no Problem even with the atd unit.The power take off should be from the idler and not from the Center of the atd unit.This works well on my Comet since 13000 miles. On my Twin I have BTH ignition and without the atd it is an easy Job.Erik

 

[bmetcalf]

The power take off should be from the idler

Any photos or sketches for details?

 

[greg brillus]

I've had a mechanical Smiths tacho on my Rapide for several years now........It looks nice opposite the 3" speedo on the other side, but in all honesty, I really don't look at it anymore. Once you know what rev's equate to a certain speed, there is no need for it........The gearbox leaks oil now, so I'll probably remove it.......... the electronic ones are nice, but you have to be careful how you wire them up.......use either the small pickup sensor that attaches to one of the HT leads, or the pickup wire that goes to the SWITCHED SIDE OF THE COIL......... not the positive side........This for either electronic or points ignition........it tells you in the instructions what to do.......If you get it wrong you will suffer issues that might cause you a case of chronic depression or similar....... It can fry the ignition coils and many other side affects. The scitsu tacho's work ok........They claim to have a run time of 10 hours on a fully charged battery........They don't suffer vibration too well........Be very careful you buy the right model for your ignition type, as it can be confusing and they won't refund you, only sell you another one........I've had a couple of them on race bikes now........first one worked ok on the twin racer, second one suffered badly from vibration above 6000 rpm, and the needle just went mad all over the place.

 

[Chris Launders]

Gary, any electronic rev counter for an older type Harley should work straight on with a D distributor I have one of the smaller (50mm) aftermarket ones on my Norvin, 0-8000 RPM I have to use a little black box though as I have twin points but if using the single points would couple straight up. Been on 20 years.

 

[Marcus Bowden]

Instrumentation I like as with oil pressure gauges voltmeter in addition to the standard stuff, my tacho is a Jaguar one mounted in a 5" saucepan(matching with my prototype 5") and only goes to 6.5k, more than adequate, Kicking over it gets to 300 RPM very sensitive.
Blue lights, handlebar heaters, next time saddle recovered fitting ass warmer! If modern bikes have it I want it too as I've spent a lot of hours in the saddle over the years, plus the fact it gives me something to do and entertains me.
bananaman.

 

[vibrac]

I am with you Marcus all that "If you need those things get a new motorcycle" just misses the point They are our bikes, if gives us pleasure to do, its all reversible and the big dog depreciation is not snapping at our heels (well it is but that's my fault for also having a 'new' bike as well )
Having and making a bike that exactly matches the output of a factory all those years ago is just as fascinating as modifying one but I long ago accepted I could have one matching numbers dream or have a lot of non matching numbers dreams of the same make that go even better. after all on the basis I ain't selling anyway whats an estimated value worth?

 

[Albervin]

A friend has a NEW Prince that was fitted with an electronic speedo (PUKA)?. Lasted about 200 miles and permanently died. The suppliers were less than helpful so a mechanical unit is now fitted. A Scitsu will allow me to get a real sense of what the engine is doing. Old engines often sound like they are working hard when they are not. I discovered this when I attached an electronic tacho. to my Riley. I thought I was revving the head off but was only doing 4,000. I am going to fit a Scitsu to my Puch and vintage Maico to get a picture of what is happening and then I may retire it or leave it on the Puch. I may do the same on my Vincents just to see what is happening, They are not expensive, distracting or ugly. To say a GPS, tachometer or even a clock, is distracting is ludicrous as you only need a split second to look at them. As far as the GPS is concerned it is more about the audio than visual except for some complicated on/off ramps.

 

[Black Flash]

@ Chris Launders,

fitted the same to my Black Flash, works a treat with my electronic ignition.
Always wanted to paint the lower part of it black, but never came round to do it.. Something to do during these long winter hours then

Bernd

Gary, any electronic rev counter for an older type Harley should work straight on with a D distributor I have one of the smaller (50mm) aftermarket ones on my Norvin, 0-8000 RPM I have to use a little black box though as I have twin points but if using the single points would couple straight up. Been on 20 years.
View attachment 37704

 

[Cyborg]

If you plan on buying one from Puca, I wish you luck.

 

[Monkeypants]

Second time around , after the tach was repaired by Smiths, they supplied a resistor to install in the circuitry. This is not in the official installation instruction pamphlet that came with the tach.

Glen