ironbutt
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Given that the Predator 670cc has two spark plugs, what's the ideal way to attach a tach?
Tach on a 670cc
- Thread starter ironbutt
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Whitetrashrocker
Inmate #952016
Is that a 2 cylinder or just 2 plugs.
Use the leading cylinder.
Or if it's just 2 plugs either will work. They fire at the same time.
Use the leading cylinder.
Or if it's just 2 plugs either will work. They fire at the same time.
ironbutt
New member
It's a v-twin with two plugs.
So both plugs fire at the same time?
That interesting. Is it one revolution per spark?
So both plugs fire at the same time?
That interesting. Is it one revolution per spark?
doesn't matter AT ALL!
the 670 is a two cylinder engine
And you need to COUNT BOTH.. unlike the smaller single cylinder clones, the twin cylinders spark at every other rotation (well they do at every, but only on one cylinder) if they have a distributor
the single cylinder sparks at every rotation (in exhaust as well as combustion cycle)
So a single cylinder tach is just counting sparks ..
to use it at a two cylinder engine, you need to count both cylinders
So count at the coil directly, not at the cylinder side if you have a distributor,
in the unlikely case of having two coils, count just one and hope that it sparks once per revolutinon per coil (just as the single cylinder would) and is not restricted by sme fancy mechanics otherwise.
I bet you can tell at idele if it's counting alright or not
I mean it either idles without revving to the moon and the tach shows ~1200rpm +/- 150 or the engine dies and the tach shows ~600rpms (+/-50 or so)
and act accordingly
'sid
the 670 is a two cylinder engine
And you need to COUNT BOTH.. unlike the smaller single cylinder clones, the twin cylinders spark at every other rotation (well they do at every, but only on one cylinder) if they have a distributor
the single cylinder sparks at every rotation (in exhaust as well as combustion cycle)
So a single cylinder tach is just counting sparks ..
to use it at a two cylinder engine, you need to count both cylinders
So count at the coil directly, not at the cylinder side if you have a distributor,
in the unlikely case of having two coils, count just one and hope that it sparks once per revolutinon per coil (just as the single cylinder would) and is not restricted by sme fancy mechanics otherwise.
I bet you can tell at idele if it's counting alright or not
I mean it either idles without revving to the moon and the tach shows ~1200rpm +/- 150 or the engine dies and the tach shows ~600rpms (+/-50 or so)
and act accordingly
'sid
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