tacho readings

[Jockney Rebel]

well the bikes maiden voyage went well ..but the suzi tacho in it reads about twice the rpm it should any ideas[?][?]

Is it a cable driven or electronically driven tacho Franken?


If it's electronic, where are you taking the signal from, one of the coil earths?

[loosebruce]

The electronic ones off 95Gsxr have a trimpot(white plastic philip head) adjustment, but not sure if it gives that amount.
Does your blke have two coils or one?
Nice work, by the way she looks the goods.

[Jockney Rebel]

its electronic chalkie and im taking the pick up from the positive side of one coil

[Jockney Rebel]

quote:Originally posted by loosebruce

The electronic ones off 95Gsxr have a trimpot(white plastic philip head) adjustment, but not sure if it gives that amount.
Does your blke have two coils or one?
Nice work, by the way she looks the goods.
ta mate the bikes handlin is miles better just need a bit more power now[}:)] ...when shes flat out the tacho reads way off the scale [it redlines at 15000] so i reckon thats about double what it should be

[loosebruce]

http://www.streetfighters.com.au/forum/upload/44915218201805.jpg

circuit diagram shows the signal coming from the box not the signal generator.

[shift1313]

if i recall that cb motor has a tacho drive off the top of the motor right? for the stock one i mean.

what tacho are you running again?

[Jockney Rebel]

im running a gsxr tacho from jarrods bike cant remmeber which year but its water cooled

[jakam04]

95 mate...

Jarrod

[Jockney Rebel]

so far since the run i need
anew sump gasket
anew cam cover gasket
a new clutch lever seal [on the casing end]
a new fuel tank [mine leaks like a sieve]
new headers
new chain
new front guard [gsx 600f or similar]
new pods[ kn s pref]
a dyno and jet up:D:D:D
fastest i got out of the old girl was 175 2 up:D

[Jockney Rebel]

quote:Originally posted by jakam04

95 mate...

Jarrod


cheers j nice to meet ya by the way

[gixkat]

175 mph is not bad mate, hehe.

hmmmm let me do the math whats that in kilowatsits an hour ?
cheers, gixkat.

[jakam04]

quote:Originally posted by frankenbiker


quote:Originally posted by jakam04

95 mate...

Jarrod


cheers j nice to meet ya by the way


For sure mate. Was great to put a face behind the voice. Hope to catch up with you again sometime, most probably next AFR lol..

Jarrod

[Deano]

the original motor dosn't run a wasted spark by any chance. the gsxr dosn't. this would cause the tacho to read incorrect.

also those clocks take a tacho signal from the ignition module not the coil.

i would have to put a multimeter on the red/black wire to find out the voltage of the signal but from memory it isn't even enough to light a test light up when the motor is running.

so if you are pumping to much power into the tacho this could explain it.

good luck

[sharky]

Same as the gpz750 clocks I tried...signal came from cdi...tacho was way out.

[shift1313]

sharky, what year gpz750? mine comes straight from one of the coils. I had a ground problem with the tach that made the bike run on 2cyls. mines an 83

[Jockney Rebel]

quote:Originally posted by gixkat

175 mph is not bad mate, hehe.

hmmmm let me do the math whats that in kilowatsits an hour ?
cheers, gixkat.
that WAS kilowhatsits an hour:D

[Jockney Rebel]

quote:Originally posted by Deano

the original motor dosn't run a wasted spark by any chance. the gsxr dosn't. this would cause the tacho to read incorrect.

also those clocks take a tacho signal from the ignition module not the coil.

i would have to put a multimeter on the red/black wire to find out the voltage of the signal but from memory it isn't even enough to light a test light up when the motor is running.

so if you are pumping to much power into the tacho this could explain it.

good luck
yeah deano i do believe it does run a wasted spark system..so does that mean no tacho ?[V]

[Deano]

quote:Originally posted by frankenbiker


quote:Originally posted by Deano

the original motor dosn't run a wasted spark by any chance. the gsxr dosn't. this would cause the tacho to read incorrect.

also those clocks take a tacho signal from the ignition module not the coil.

i would have to put a multimeter on the red/black wire to find out the voltage of the signal but from memory it isn't even enough to light a test light up when the motor is running.

so if you are pumping to much power into the tacho this could explain it.

good luck
yeah deano i do believe it does run a wasted spark system..so does that mean no tacho ?[V]


i am sure you would be able to get it up and running some how. may take a bit of electronic trickery but i am sure someone on this forum will have the answer. unfortunatly i have no idea

[Jockney Rebel]

this explains a lot to me its reading almost twice the rpm it should be soooo there fore its picking up the wasted spark and registering that right ? anyone ? maybe if i run it from the pick ups?

[loosebruce]

Try the white phillip head adjuster on the tacho PCB.
Could work,but it might only give a range to calibrate within.

[Jockney Rebel]

ok bruce ill give it a go....ta mate

[Deano]

quote:Originally posted by frankenbiker

this explains a lot to me its reading almost twice the rpm it should be soooo there fore its picking up the wasted spark and registering that right ? anyone ? maybe if i run it from the pick ups?


if you have a wasted spark then yes you are right. just swap number 1 and 2 plug leads, if it still runs normal then you have a wasted spark and yes the tacho will be reading that.

i assume you only have the tacho hooked up to one coil and not both?

[Jockney Rebel]

yeah just the left hand positive

[shift1313]

if you have a wasted spark i believe you can build an op-amp circuit between your coil and tacho. Im sure someone here can give you insight into this as im more mechanical. I could figure it out but would take me awhile:)

[megareg]

A flip-flop would be better, halves the signal, interesting problem though..

[Jockney Rebel]

flip flop ? the only flip flops i got are for me feet [hang on u lot call them thongs dunt ya ]:D im intrigued mr reg and electrically challenged so go easy on me [i know how to use a multi meter tho ]:D

[megareg]

No worries franken, the're also known as "Jandals" in NZ, but anyway, a flip-flop will take one pulse to turn the output high and another pulse to turn the output low, in effect, it halves the frequency or in other words, 2 pulses in for 1 pulse out, I just wonder if the output to the tacho has a high AND a low signal, and the tacho is reading that, perhaps a diode in series with the output would fix it??? right now, I have my trusty Fluke meter at home with me, it can read frequency and would soon find out what it is. Mate, its a good thing you can use a meter... I have tradesmen at work that have problems reading!!!

Cheers.

[Jockney Rebel]

quote:Originally posted by megareg

No worries franken, the're also known as "Jandals" in NZ, but anyway, a flip-flop will take one pulse to turn the output high and another pulse to turn the output low, in effect, it halves the frequency or in other words, 2 pulses in for 1 pulse out, I just wonder if the output to the tacho has a high AND a low signal, and the tacho is reading that, perhaps a diode in series with the output would fix it??? right now, I have my trusty Fluke meter at home with me, it can read frequency and would soon find out what it is. Mate, its a good thing you can use a meter... I have tradesmen at work that have problems reading!!!


Cheers.
ive a basic understanding ..not much use for a multimeter in hydraulics lol:D
thanks for the info reg

[Jockney Rebel]

d y reckon i cuold get away with running it off one of the pick ups at the end of the crank?

[shift1313]

i dont think so. if your pulling it off the pickup or the coil it should be pretty close to the same(cdi just advances a bit off the pickup). Your problem is the type of signal the gauge wants and the type you are getting.

if your feeling brave
http://www.josepino.com/pic_projects/index?tachometer2.jpc

[Jockney Rebel]

kin hell matt thats wayyyyy beyond me im gonna try running it from somewhere else cos im already thinking of an acewell unit from ben to replace the cluster the carbs are my first concern tho

[megareg]

Shame your so far away, still, Woy-Woy is a nice place to live, and that "old road", I remember it well, although a long time ago now, I had many a nice day scratching around on it.... I used to live in Lithgow and did a fair bit of riding around..
Here is another link for something that is interesting..

http://www.tach.rex-deb.net/

I'm playing with Picaxe's at the moment...
If you have a look at the temperature reading on the top left of the webcam piccie, that is my work.. http://www.inghamwebcam.com/
It's my brothers website

Cheers mate, and I hope you get it sorted.

[Jockney Rebel]

ta reg