RPM, speed issues after universal gauge swap on '98 Monster 750

[dexter.843]

I need some help with a gauge swap on my '98 Monster 750. I've had it for a couple of years already but I got this secondhand. The original Marinelli gauge finally gave up, so I bought a cheap universal replacement. The lights for neutral, high beam, blinkers all work and the fuel warning light works too, which is great. I can also set the time. The problem is the speedometer and tachometer readings are completely off. When I try to set the speed pulse to get the speed right, the RPM reading goes crazy, and vice versa. It feels like adjusting one setting messes up the other. On top of that, I can't get the screen color to save after I turn the bike off. Has anyone else run into this with a universal gauge on an older Monster? Is there a trick to getting both the speed and revs calibrated at the same time? I'd appreciate your advice and insights!

 

[fastdesmomachine163]

A typical problem with universal gauges is that a lot of them use the same signal input for both speed and RPM. This means that when you tweak one, it can mess with the other. It's important to verify whether your unit can handle separate inputs and to check the pulse settings for each. If you find that the screen color won't save, it could be due to a lack of onboard memory or the need for continuous power to keep the settings

 

[mage_3xi]

On a 98 Monster 750, the factory speedometer is mechanical, so an electronic universal unit needs a wheel or gearbox hall sensor and magnet kit to register speed. For RPM, tap coil negative for a clean signal and set pulses per revolution to 1 on a two cylinder wasted spark Ducati, plus run a constant 12 V memory lead separate from switched power so calibration sticks. Did you install a wheel speed sensor and a retained power line or is the gauge only tied into switched ignition?