I'd like a tach just to set idle speed (Honda VT600) as recommended by the
manufacturer.

What one should I get?

Are there any that work using a microphone only?

Thanks.

On 5 Mar, 07:04, "David T. Ashley" <d...@e3ft.com> wrote:
> I'd like a tach just to set idle speed (Honda VT600) as recommended by the
> manufacturer.
>
> What one should I get?
>
> Are there any that work using a microphone only?
>
> Thanks.

If you get a decent strobe gun, that'll have a tacho built into it,
but if all you want is to set the tickover, why bother spending your
money? Just set it to whatever level you feel happy with. As a rough
rule of thumb, with a hot engine, turn it down until it is nearly
stalling, and then tweak it slightly higher than that. It won't break
if it's a couple of hundred rpm out from what Mr Honda recommends, you
know.

On Mar 4, 11:04 pm, "David T. Ashley" <d...@e3ft.com> wrote:
> I'd like a tach just to set idle speed (Honda VT600) as recommended by the
> manufacturer.
>
> What one should I get?
>
> Are there any that work using a microphone only?

I use an old Craftsman engine analyzer with a narrow
band tach setting and hook straight in to primary -12
volts at the coil.

For a twin with wasted spark ignition (1 spark per rev),
the four cylinder setting reads exactly half the real
RPM.

Cost was under $20. Useful primarily for equalizing
the cylinders.

Using a 4mm threaded extension between the plugs and
plug leads, short out first one cylinder then
the other, observing RPMs when it's running only on
the unshorted cylinder. Adjust the running cylinder
RPMs up or down as needed until they match, then
adjust both sides up or down by equal turns until
the desired idle speed is achieved.

For an air cooled bike, you may also want a fan to
keep engine temps under control.

David T. Ashley wrote:
>
>Are there any that work using a microphone only?
>

If you've got a Windows or Pocket PC, this one is free :

http://www.tunelab-world.com/rpmsound.html

I've used it on airplane engines and it's worked very well. Never tried it
on a bike, though.

John

--
Message posted via MotorcycleKB.com
http://www.motorcyclekb.com/Uwe/Foru.../bike/200803/1