Honda VT750 ignition pulses for aftermarket tach
Posted: Fri Nov 23, 2007 3:04 am
Good day gent's & ladies of course,
I would like to ask you riders for a fresh mind & tech wisdom. I would call manufactuer's tech line but they are shut down for Thanksgiving wknd, Aargh !
I recently acquire a 01 VT750DC & because it has no tach, I've purchase a "TrailTech" Vapor ride computer with bar graph & digital tach and keeps track of a multitude of info. After alot of button pushing trying to set computer for ignition pulses per revoluion {ppr} I'm frustrated & feel like a idiot/dweeb.
Tach pick-up/sensor wire is wrapped around one spark plug lead wire,{10 wraps as instructed} It's reading the pulses but apparently reading too many pulses, possibly from close proximity to other lead going to same cylinder but second spark plug. But in my understanding, timing/trigger signal for coil is going to send pulse down both wires at same time when coil fires.
Manual states that majority of vehicles {four-stroke engine} are 1 ppr, while two strokes use 2 ppr setting {duh! easy enough} Neither setting is displaying an accurate rpm via my hand held digital tach/test meter.
What I seek is the "yoda" on this honda ignition system. I realize that maybe each coil {one coil for two spark plugs in each v-twin cylinder} may fire at combustion & exhaust stroke.
Does anybody have a solid lead/clue on what I'm doing wrong or overlooking/under-thinking? These computers are reliable & accurate not "chinese junk" as I have them on my offroader & dual-sport scoots. Somebody please slap me around with any wisdom/experience that you have stored in your RAM, mine has got run over by a Dodge truck & don't function as it should.
Thanks for any info & your time sharing the knowledge, hoping you all had a great thanksgiving w/family & friends, hoping that you always be thankful for those who make it possible,
JP
I would like to ask you riders for a fresh mind & tech wisdom. I would call manufactuer's tech line but they are shut down for Thanksgiving wknd, Aargh !
I recently acquire a 01 VT750DC & because it has no tach, I've purchase a "TrailTech" Vapor ride computer with bar graph & digital tach and keeps track of a multitude of info. After alot of button pushing trying to set computer for ignition pulses per revoluion {ppr} I'm frustrated & feel like a idiot/dweeb.
Tach pick-up/sensor wire is wrapped around one spark plug lead wire,{10 wraps as instructed} It's reading the pulses but apparently reading too many pulses, possibly from close proximity to other lead going to same cylinder but second spark plug. But in my understanding, timing/trigger signal for coil is going to send pulse down both wires at same time when coil fires.
Manual states that majority of vehicles {four-stroke engine} are 1 ppr, while two strokes use 2 ppr setting {duh! easy enough} Neither setting is displaying an accurate rpm via my hand held digital tach/test meter.
What I seek is the "yoda" on this honda ignition system. I realize that maybe each coil {one coil for two spark plugs in each v-twin cylinder} may fire at combustion & exhaust stroke.
Does anybody have a solid lead/clue on what I'm doing wrong or overlooking/under-thinking? These computers are reliable & accurate not "chinese junk" as I have them on my offroader & dual-sport scoots. Somebody please slap me around with any wisdom/experience that you have stored in your RAM, mine has got run over by a Dodge truck & don't function as it should.
Thanks for any info & your time sharing the knowledge, hoping you all had a great thanksgiving w/family & friends, hoping that you always be thankful for those who make it possible,
JP