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cant find a small size tachometer for my fxdc, dont want the four inch monster so i bought an older tach for pre "serial" bikes. only has hot, ground and impulse input wires. it is a stock harley part, for older bikes.
thats all fine and dandy but my bike doesnt have a convenient tap for the impulse input cause the coil uses two inputs to fire, not one as on older bikes. so the coil is out as an input.
looking at the schematic, it seems probable that the crankshaft position sensor is a good place to tap in for this pulse. seems to me anyway. havent tried it yet so i cant answer my own question.
any of you guys got an idea for this one?
gringo
 

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cant find a small size tachometer for my fxdc, dont want the four inch monster so i bought an older tach for pre "serial" bikes. only has hot, ground and impulse input wires. it is a stock harley part, for older bikes.
thats all fine and dandy but my bike doesnt have a convenient tap for the impulse input cause the coil uses two inputs to fire, not one as on older bikes. so the coil is out as an input.
looking at the schematic, it seems probable that the crankshaft position sensor is a good place to tap in for this pulse. seems to me anyway. havent tried it yet so i cant answer my own question.
any of you guys got an idea for this one?
gringo
Probably ain't gonna work ... The older ignitions were twin fire versus the newer single fire ignitions . The early tachs were designed for twin fire only , a pulse per engine revolution . The CKP works off of a 5v. signal whereas the tach works off a 12v. signal .
You MIGHT TRY splicing the coil signal wires to the single tach signal wire to see if it'll work ! Might need a couple diodes in the splice too !
 
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