Z750 FI warning light, think I worked it out?

[Trox]

The fuel injection warning light came on my '08 Z750 a little while back and I've had the bike pulled apart in the garage for a while now and think I've worked out what the problem is and what I need.

I've done some research and I think I could actually do nothing and it will be fine however that will leave me with an annoying warning light permanently up, anyway this is what I've found out......

1- the original exhaust has an exhaust ultimate power valve (EXUP) that opens and closes relative to whether you are idling through to opening it right up.
2- I bought it with an IXIL Xtreme exhaust which does not have this valve (as most after markets don't)
3- the valve is controlled via a servo motor on the LHS of the bike.
4- normally in the kit for the exhaust is a plate that you attach to the servo motor replacing the pulley on it (which has cables running to the valve on the exhaust). This plate is to fool CPU so that the FI light doesn't come up.
5- all of the above is fine but my warning light is on and upon further investigation the servo motor is cactus....seized cog and burnt out.
6- I have come across a little 'adapter' called a servo buddy (can get from eBay for about $80) which is supposed to eliminate the need for the servo motor all together leaving no warning light coming up, you just plug it in where the servo motor would normally plug in to.

Does anyone know of these 'servo buddy's' and if what I've researched and investigated is correct?

Cheers in advance

[fireyrob]

Used a few servo buddy's on different bikes. $80 seems exe I think I paid about $40 but that was a couple of years ago.

If you research there are some threads (possibly even on here) on how to make a servobuddy yourself if your handy at that stuff.

[Trox]

Thanks for that Rob, yeh I got a diagram (I think it was a link from one of the thread on here to another forum).
Got the parts this arvo for $6-7 got home and soldered it up and thought I'd test it before covering in epoxy and it worked perfectly , unfortunately when I covered it in epoxy after it created a bit of heat and destroyed the diode (open circuited it - may have also been the epoxy not allowing heat to dissipate) so ill b going back to jay car tomorrow for another $2 diode and some other way to insulate the bare conductors (it's too tight to get heat shrink on to it)
Circuits as follows for anyone reading this and wanting to know;
470uF electrolytic capacitor - negative connected to the black lead,
220ohm 1/2watt (I used 1W) resistor - one side connected to the red,
4.7k ohm 1/2watt (again I used 1W) resistor - one side connected to the yellow lead
White and grey leads left disconnected
Other side of both resistors and positive of the diode connected together

[fireyrob]

Good result. I know who to PM if I ever need one made up

[Trox]

Be happy to mate
Well I made another one this morning and used some electrical tape and heat shrink instead of the epoxy.....
Plugged it in and switched the ignition on and it worked
However.....
I've found out if I turn the ignition on (or turn the bike on as well) within half an hour of the ignition (or bike) being on the light comes back
At one point today i took off with the light on because i stopped for less than half an hour but while I was riding the light went away, when I got home I turned the ignition on again within half an hour of it being on and the light came on again so I'm not quite sure what the go is.....

[fireyrob]

Hmmmmm sounds like a connection issue. It shouldnt do that. I doubt its to do within the 30 mins, more like your home made contacts and heat whilst bike is still warm? You sound more electrically minded than I but maybe someone else can help?

[6maniac]

Trox, I replaced my 2008 Z750 oem can with a Delkevic.

Just removed the cables from the servo, and have had no FI light issues ..

[s man]

Trox, I replaced my 2008 Z750 oem can with a Delkevic.

Just removed the cables from the servo, and have had no FI light issues ..

Yep same same..

[Trox]

Unfortunately when a previous owner installed the exhaust they did a poor job and has resulted in burning out components in the servo motor and consequently the sensor circuit tells the ecu there is an issue therefore I either have to replace the whole servo motor (which includes the sensor circuit) or bypass it with what should be a relatively simple circuit, cheers for the input tho
I don't think it's a loose connection, it seems to have more to do with timing and/or the revs the motor is doing thus I think the circuit I have followed maybe missing something or the timing of it is incorrect (it's a simple RC timing circuit) think I'm close to nutting it out