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Discussion Starter · #1 ·
Has anyone tried or does anyone know if the Tack and Speedometer off any of the 4 cyl Honda bikes can be made to work on the 6 cyl -- aka GL1500.

Socks
 

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1996 Honda GoldWing Interstate, Candy Spectra Red, and of course, with drive shaft.
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GL, thanks for the reply ---- I haven't thought about a Valkyrie ----
Are you looking for the instrument cluster or the cables? And then, isn't the physical size of these something to consider? As for compatibility, since these instruments are cable-driven (from everything I'd seen researching the question...hmmm,, who knew? I thought tachs used an electrical signal...and even then I might have seen evidence that the later GoldWings do) RPM is RPM, so it shouldn't matter whether the tach is from a 4-cylinder or a 6. Ah, but then again, I seem to recall when I'd last used an automobile service tachometer, and there was a "4/6/8" cylinder switch...none of which would come into play if the tach is cable-driven. As for the speedometer, that's driven by a cable, surely (I just replaced mine on my GL1500) and there the scale would be calculated to the size of the front tire. Has that changed from the GL1000/1100 to the GL1500? Someone else know? (Sorry for the stream-of-consciousness reply...I don't presume to be an expert here, but having owned both a GL1000 and my current GL1500, I can see you may something of a challenge.)
 

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Discussion Starter · #5 ·
Are you looking for the instrument cluster or the cables? And then, isn't the physical size of these something to consider? As for compatibility, since these instruments are cable-driven (from everything I'd seen researching the question...hmmm,, who knew? I thought tachs used an electrical signal...and even then I might have seen evidence that the later GoldWings do) RPM is RPM, so it shouldn't matter whether the tach is from a 4-cylinder or a 6. Ah, but then again, I seem to recall when I'd last used an automobile service tachometer, and there was a "4/6/8" cylinder switch...none of which would come into play if the tach is cable-driven. As for the speedometer, that's driven by a cable, surely (I just replaced mine on my GL1500) and there the scale would be calculated to the size of the front tire. Has that changed from the GL1000/1100 to the GL1500? Someone else know? (Sorry for the stream-of-consciousness reply...I don't presume to be an expert here, but having owned both a GL1000 and my current GL1500, I can see you may something of a challenge.)
CBC -- Thanks for the reply. It's obvious I am searching for info. I assumed (that's always dangerous) the tacks were all electric. The actual size -- to a point isn't a factor since I'm fabricating the dash panel. I was hoping to find 2 gauges abt 3-4". I realize the speedometer would probable have to be calibrated for accuracy. Someone suggested Valkyrie gauges so that's an option if the tach is electric.
I'm open for ideas and or suggestion.

Socks
 

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Hey Socks - The early tachometer used by the GW only looks at one of the coils for it's trigger. The 4-cylinder bike (two coils) and a 6-cylinder (3 coils) electronic RPM pulse counter works the same. The "Pre-Fuel Injected 1800" tach's internal circuitry ignores one of the two trigger pulses it receives per crank revolution. The tachometer on the later Coil Over Sparkplug Ignition (COSI) system only receives a single trigger pulse from cylinder #1.

The reason an older type generic automotive tach had a selector switch to differentiate between a 4 - 6 -8 cylinder engine was because all the plugs shared a single distributor/coil. To read RPM accurately, it's divider circuit had to know a starting point for each revolution (the logic circuit would just pick one) and how many cylinders it was dealing with.

Good Luck and Ride Safe - Michael
 

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1996 Honda GoldWing Interstate, Candy Spectra Red, and of course, with drive shaft.
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Hey Socks - The early tachometer used by the GW only looks at one of the coils for it's trigger. The 4-cylinder bike (two coils) and a 6-cylinder (3 coils) electronic RPM pulse counter works the same. The "Pre-Fuel Injected 1800" tach's internal circuitry ignores one of the two trigger pulses it receives per crank revolution. The tachometer on the later Coil Over Sparkplug Ignition (COSI) system only receives a single trigger pulse from cylinder #1.

The reason an older type generic automotive tach had a selector switch to differentiate between a 4 - 6 -8 cylinder engine was because all the plugs shared a single distributor/coil. To read RPM accurately, it's divider circuit had to know a starting point for each revolution (the logic circuit would just pick one) and how many cylinders it was dealing with.

Good Luck and Ride Safe - Michael
I don't know why this has become such a thing for me...perhaps just the challenge of researching it, but to all appearances the GL1100 tach (like the GL1000, which, when I looked at the schematic, showed no signs of an electrical signal to the tach, only the temp meter) is cable-driven. The GL1500 (and up, I'd have to think) shows an electrical connection to the "engine control module". Here's a picture of the back of what's claimed, on an EBay listing, a GL1100 tach.
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Hey Socks - Both the GL1000 and GL1100 do use a mechanical cable driven tachometer. I thought you were asking about information on the possibility of installing an alternative tachometer on a GL1500 GW ? The 1984 - 1987 Interstate 4 cylinder tachometer triggers off one of the coils similar to the 1988 - 2000 GL1500. The 1984 - 1987 Aspencade with the digital dash is a different animal.

"Has anyone tried or does anyone know if the Tack and Speedometer off any of the 4 cyl Honda bikes can be made to work on the 6 cyl -- aka GL1500."

Michael
 
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