i have a custom bike with no room for the stock gauges anymore.

i tried to do the trailtech thing that a lot of stripped down motorcycles use, but the reed sensor magnet junk and the small hard-to-read lcd with a poor backlight were just no good

i reset my goals to 'visible without staring at it' and 'small' and 'uses stock speed sensor'

so i've set out on a mission to turn these two things into my new instrument cluster:





they were really cheap, and the display and board together are about 1.25x2".. all the lcd units i saw had fairly low visibility.

it's turning out to be easier than i thought to get all this working on the bench

the display connects to the arduino over SPI, so only need 4 wires to the dash (power, ground, and two for comms), then i'll hide the arduno near the airbox somewhere. i haven't actually powered up the display but i've heard they're bright as fuck (dimmable on command of course)

i've managed to get the stock speed sensor working reliably with the analog input on the arduino (luckily it was already 0-5v). used a voltage switching point, only counting the rising edge. it runs up its counter for a fixed length of time, calculates for hz and starts over. it will have two accumulators for trip and odo too.

i figured out pulses per wheel rotation by marking my tire and spinning it a few times while spitting out total pulses on the arduino's serial port

most of the other sensors (oil, FI error, fuel reserve, etc) when run to the stock gauge pull to ground when in a bad state, so it looks like can use the arduino's internal pull-up and plug 'em right into the digital inputs. one exception is the signal indicators, but i think i'll throw a small relay and a few diodes in there so it'll just ground a pin when they're flashing too.

my idea for the display logic itself (since there's a bunch of input data but only 4 digits to roll with) is to automatically cycle between all available data, which when normally riding and everything else is normal, is just the speedo.

for example if oil pressure goes low while in motion, it'll flash 0IL, speed, 0IL, speed. if stopped, and the speedo was zilch, it would just display 0IL.

it has those decimal point dots, i might use that as neutral light? signal indicator? (might be too small, we'll see)

still haven't figured out a housing for the display yet, how/where to mount it, or how to protect or power the arduino itself which definitely needs to be weatherproof, but it's almost a gauge.

anyone else made anything like this or see any disasters approaching?