Several years ago I scored a perfect condition NOS stock CB650 tach for $99 and shipping when shipping was still inexpensive. because I was going to drop a CB650 cam in my CB550 I have been amassing parts for its rebuild and restore. I found a nice cam and camshaft gear from a member here before they surged in prices. You can still find a good deal but it is rare.
Know a guy in Australia who has designed a cool stepper motor drive instrument that can give you a ton of info and can drive a tach as the needle driven instrument. With proper sensors it can display tach and water temp and voltage of course as well as fuel if you can engineer one into the tank if it didn't have one. It has mileage and trip functions and if given fuel signal it can aleet you to low fuel. Then there are other functions as well as odometer. It fits in your existing speedo or tach cade and uses the needle, faceplate and glass. You cut an opening for the two OLED displays built into face above and below the center of the needle.
Went and grabbed the description Ray's website.
Rae-San Dash Meter
Dash meter with glass and needle on – glass and needle not supplied – reuse existing.
The Rae-San Dash Meter is designed as a modern electronic replacement for original motorcycle gauges.
I t provides a stepper motor driven needle indication of speed or RPM (configurable) that is able to be adjusted to suit the original face plate and graduations on the face plate, providing a means to update and replace the old gauge mechanics but maintain the original look of the dash and to use the same gauge mounting buckets.
The gauge re-uses the face plate, needle and glass, but everything else is new and electronic.
In addition to the needle movement it provides two OLED displays that are configurable by the user to provide displays of several quantities.
The Gauge is able to measure and display the following quantities.
Fuel, Coolant Temperature, Oil Pressure (with appropriate sensor) Speed, Tacho (RPM), Odometer, Tripmeter, Clock ( with optional clock module), System voltage and Gear selected (calculated from RPM/speed).
The Fuel measurement can be done from an analog sensor, or on fuel injected motorcycles by measuring the accumulated injection pulses.
Using the injection pulses gives a very accurate fuel indication and allows for the measurment of the actual fuel used. Calibration occurs at the first refuel where the user adjusts the fill amount on the display. From there just reset the fuel tripmeter when filling the tank. Additional displays with litres remaining, distance to empty and fuel economy can also be selected.
The Gauge supports 4 profiles, and each profile allows for 4 display configurations – which are able to be cycled though with button presses. Supplied with a base set of profiles to support common bikes.
Support for two buttons is provided – for clock setting, display cycling, trip reset and activation of programming or check mode.
All inputs are configurable allowing for different sensor input ranges, wheel circumference adjustment, correction of the gauge and sensor non-linearity etc.
White Back lighting is provided to allow for face plate illumination. OLED display is white to allow for daylight readability.
Gauge configuration is performed usb connection using a simple ANSI terminal (such as Putty).
The gauge is available in a number of sizes to suit the face plate and gauge bucket diameter of a large range of motorcycles.
For those wishing to completely replace the original gauge cluster, 3d printed outer housings (gauge buckets) and diagnostic light clusters are also available to support building a custom dash.
https://www.rae-san.com/rae-san-dash-meter-2/He has accessories products for the dash meter. Ray has been designing and testing lots of products starting out with CDI power supply for the CX / Gl 500 and then developed replacement CDI ignition and TI ignition using Hall effect sensors for crank positioning and similar needs of the replacent ignition sustem. CDI boxes fail as well as high and low speed coils, all of which are NLA. He stsrted on his ignition system before the Ignitech product came out for the CX and GL bikes. His designis far better and easier to install and has been optimized for several profiles and performance levels as some guys have managed to find performance build solutions using other bikes parts to bore and port and carburator upgrades as well as other changes guys have come up with.
Murray Feldman has been behind a bunch of those solutions as well as enthusiast in AU and the UK.
Anyway...
Tach/Speedo instrument goes for $200-215 plus shipping and sensors he carries are extra. Then of course freight from the land down under...
The insert is a drop in into your housing replacing the guts of the instrument and and as I spreviously mentioned it uses your glass needle and faceplate.
So buying a new faceplate, glass, and crimp at Marcel's or get a faceplate decal from someone else. I don't know any sources for the glass and crimp-ring besides Marcel. I spoke to him in late October but Terry mentioned it was crickets when he emailed him about his K0 instruments...
Ray is a great guy and very trustworthy. Many members on CX/GL-500/650 forums are satisfied customers.
Murray Feldman is in NC and sells Mikuni carb solutions along with some other stuff. He used to do the CX-GL performance motor rebuilds but quit doing it after or bit before having neck fusion surgery a couple years ago.
Of course your bike wouldn't look right with a modified tach or speedo but it makes a great option for a customized runner and not a collector bike...