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Old 09 March 2016, 03:35   #71
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There's another thread on these cheap tachs... I have one... when it registered 2946 as the WOT RPM Poly pointed out that my low idle revs of around 300 were probably 50% of what i was actually doing, ditto at WOT... perhaps your tach is like mine and reading 50% of actual.
thanks stig not an expert but mine seams to be reading 1/3 ish i wonder if its because its only on one lead out of three?

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Old 09 March 2016, 03:46   #72
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Jeff you said above the tach was showing 220/210rpm and your Suzuki has an ECU controlled idle speed of 850rpm +/-50 so more like it's showing 1/4 revs.

I forget which small tach you have but does it allow any setting changes in a menu?
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Old 09 March 2016, 03:49   #73
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1/3 sounds better... I have 2 cylinders and therefore your assumption could be correct. I tried wrapping the tach lead round both HT leads to see if it made any difference but I still got revs counted in the 300-450 range (engine wan't warm so it wasn't idling without a little assistance every so often)
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Old 09 March 2016, 04:25   #74
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There seems to be more than a few guys of late reporting some fairly wild readings off your cheapo tachs.
They are usually adjustable and below are some instructions on set up, which hopefully may help you get more realistic readings.
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Old 09 March 2016, 04:32   #75
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Can't speak for others, but mine has no buttons, controls, switches or other means of input... It has an LCD and a wire, nothing more... But you get what you pay for...
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Old 09 March 2016, 05:47   #76
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Still sounds too low - idle of 440? Maybe it's 25%??
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Old 09 March 2016, 05:48   #77
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Still sounds too low - idle of 440? Maybe it's 25%??
What happened there? Just replied to the Suz' topic??
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Old 09 March 2016, 06:38   #78
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>>>What happened there? Just replied to the Suz' topic??

Well you did... this is the Suzuki topic!

>>>Maybe it's 25%??

Yep pretty sure of that... as I mentioned above these Suzuki's have a fixed idle maintained by the ECU at 850 +/-50 so if you like you can use the outboard to check/set the tach.

The tach I bought has 7 spark sensing modes for different engine types. It shows how to select in the menu for the various options but then has a final note that if it looks wrong at idle it probably is... so to change the mode to one that gives a more realistic idle then it will be correct for higher revs.

Also I mentioned in the tach thread I made sure I bought one with a coax sensor wire with a ground wire for the shield which is how the expensive Tiny Tach is made. I can see there is a real possibility in more modern engines... particularly the EFI models with injector wiring... for stray pulses to upset the tach model with a single core wire.
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Old 09 March 2016, 07:15   #79
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guys didn't really research the tacho because i was just after the hour meter originally but mine is a cheapo no buttons so probably no good so i get another sorted and to be honest its fell apart twice it is sealed but looks like not whats needed.
which one did you buy david
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Old 09 March 2016, 07:32   #80
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It was this one Jeff..

Digital Hour Meter Tachometer Adjustable Resetable Job recall max rpm + service | eBay

Of course I haven't tried it yet as the Suzuki isn't here. It should have arrived at Suzuki UK in Milton Keynes on Monday with a possible arrival at my dealer today, next Wed at latest.

I'm trying so hard to be calm and not to ring them jumping up and down... "Is it here yet"!
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