Re: Harbor Freight Tachometer

as far as i know, with tachs like this, there is no happening when you use the little switch for 4-6-8, it just changes the resistance, so bust the thing open, play with some resisters and print a new dial on some glossy photo paper, that's mopeds

Re: Harbor Freight Tachometer

Ross Maser Wrote:

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> So much for an old man giving you room to dig

> yourself out.

>

> The distributor of a 4 stroke rotates at cam

> speed, which is half of crank speed.

(edited)

Re: Harbor Freight Tachometer

Jason Collier /

Re: Harbor Freight Tachometer

Blaine- The artist formerly known as Plumber Crack "(OFMC)" /

Jason Collier Wrote:

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> just use this

>

> http://www.ebay.com/itm/300701766592?ssPageName=ST

> RK:MEWAX:IT&_trksid=p3984.m1423.l2649

I believe, in their description, they have the wiring(lines?) all screwed up.

Guessing at wiring= Smoke!

Looks like ALL their wiring insrtuctions are guesses, and poorly translated too.

It isn't how i would wire it.

Re: Harbor Freight Tachometer

because this tach is supposed to be sensing the impulse from a single ignition coil running through a distributor, the waste spark/ non waste spark is a moot point. take the # of cylinders and divide by 2 to get the number of coil impulses per engine rotation (4 stroke) so for example, a v8 has 4 coil impulses per revolution to a 4 cylinder's 2 coil impulses. it goes without saving that a two stroke has a coil impulse for every cylinder per revolution.

SO, if the tach is set to 4 cylinder(4stroke) mode, then it will interpret the 1 impulse/rev. of a single cylinder 2 stroke as 1/2 of a revolution of a 4 cyl. 4 stroke (2 impulses/rev.)

IF the impulse were to be taken from a single plug wire of a multi cylinder 4 stroke with a waste spark electronic ignition (like virtually ALL modern vehicles) then there would be no difference in the number of impulses per revolution between a two stroke or four stroke engine, reguardless of cylinder count. this is how the trail tech tach works.

pretty fuckin simple in the grand scheme o things imho.

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