REQ: Tach circuit for motorcycle (bargraph)

[me]

looking for ideas (diagrams) for a bargraph tach for a motorcycle
Vtwin cylinder like a lm3914 with led's and a interface led per 500
rpm 0-5000 Thanks

 

[Wim Ton]

looking for ideas (diagrams) for a bargraph tach for a motorcycle
Vtwin cylinder like a lm3914 with led's and a interface led per 500
rpm 0-5000 Thanks

I built something similar for the owner of a 1930 Benz. It uses Honeywell

GT1 sensors picking up a signals from the bolts on the flanges that connect
the driveshafts to the gearbox.

The processor is an Atmel AVR 2313 with 50 LEDs in a matrix
configuration, (8 columns driven by a ULN200? and the rows driven by NPN's
driven by a 4028 decoder. I had to add a FIR filter as the input turned
out to be quite noisy.

Wim