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Rpm Wiring Koso Rx2n

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#23 ·
tritchy82 said:
Yeah but why wrap it around the spark plug? I dont see the reason haha
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Cause the spark plug ignites the same amount of times, IE electricity gets sent through that wire...
 
#27 ·
JBYZF said:
its not for stupid people if you cant get it to work without it ;)
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If you can't get it to work without it you ARE stupid ;)

(Joking, so noone gets offended)
 
#28 ·
tritchy82 said:
Yeah but why wrap it around the spark plug? I dont see the reason haha
Click to expand...
i would assume that the high voltage travelling to the spark plug induces a current (from the electro-magnetic waves produced by the signall travelling to the spark plug) into that of the rps signal wire.. more times wrapped round the spark plug wire = higher current induced = better signal for the tacho. sorry if i've used a load of techy words there :L tried to make it simpleish for if someone doesnt understand electronics too much but not sure how well i did :L
 
#29 ·
Avtech93 said:
i would assume that the high voltage travelling to the spark plug induces a current (from the electro-magnetic waves produced by the signall travelling to the spark plug) into that of the rps signal wire.. more times wrapped round the spark plug wire = higher current induced = better signal for the tacho. sorry if i've used a load of techy words there :L tried to make it simpleish for if someone doesnt understand electronics too much but not sure how well i did :L
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You did well ;)
 
#31 ·
If you were going to put it on the spark, you'd probably want to do it before the coils wouldn't you?
The spark plug has quite an unstable electrical signal (being a spark), whereas the initiating current would be a more stable pulse.
 
#32 ·
I assume that before the coil would be a very small signal, it doesnt need a stable signal all it needs is the big voltage spike, the rpm is calculated by counting the amount of these spikes..... I think :L
 
#34 ·
Avtech93 said:
I assume that before the coil would be a very small signal, it doesnt need a stable signal all it needs is the big voltage spike, the rpm is calculated by counting the amount of these spikes..... I think :L
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It won't need a large voltage to run. I've just been reading the KOSO manual and it recommends pre-coil if you can't find the original tach wire, the spark splug just isn't a good reliable source as the actual signal wires on other parts of the bike.

Any progress yet Dimitri?
 
#36 ·
Avtech93 said:
Fair enough xD I was just educated guessing at how it may wrong never said I knew I was right lol
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No it's good logic, as long as the spark plug was a single high-powered pulse, but sadly it's not; it's got some big interference in it, due to the way the spark is actually generated
 
Discussion starter · #39 ·
Nope, still no progress..
When wrapped around the spark cable, the tachometer doesn't work well..
But I've also seen that the engine management light is on because I disconnected the original speedometer :p
Maybe that why I can't find any wire that gives the rpm?

I will take a look at it next week, because I've already put everything back on.

I also find it weird that when connected to the negative side of the coil, I don't get an rpm signal...
I've measured it and it gives a raising voltage as soon as you rev (starting from aprox. 12v)
 

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Dimitri
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