VBoost Operation "noise"

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gavicool

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Vigo-Spain
Hello,I have a problem since I install back the Vboost "buterflys" ;Yamaha year 86(USA ,not CA model) ,KerKer + Dyno7.
Problem;
The bike had the controller and servomotor installed and "conected" before I install the "Vboost hardware",no noise before,(before the installation,without the vboost,the servomotor and controller were working,even when they did not have any influence,aren´t they?....).
During Vboost operation a "noise" get off (similar to when a relay get failure due to a continuing contact").
I change the fuel relay and fuel pump(second hand parts...)
I disconect the servomotor conector (to keep the Vboost open al the time),to try to identify the problem(Controller or Servomotor..I thought...) ,but what happen after I start , is that the Fuel pump does not stop the operation,always running....
I stop the bike and reconect the the servomotor,fuel pump start and stop normal....

Hope to get good "tracking" of the problem,as usual..🍻

Regards from Vigo(Spain)
 
Pretty-sure that the VBoost has some function in its controller or the relay for the fuel operation. Sean will know.

There's a yellow wire from the VBoost servo motor and the fuel pump relay which go to an ignition coil and the ignition control unit. That appears to be for 1990-'03 models.

On the '85-'89 models the wire is red/white and runs from the fuel pump relay and the VBoost controller to the ignition advance unit.

VMax USA 85-89 wiring.png
VMax USA 85-89 wiring lower.03.png
 
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Pretty-sure that the VBoost has some function in its controller or the relay for the fuel operation. Sean will know.
Thank you *Fire-medic.
I think so..but what its extrange is that before I did not have any "issue" ,fuel and controller were "working" even whithout the buterflys removed...
I just want to eliminate parts involve in this failure..my first thought was the fuel relay also....and since my last test(servomotor disconection),I´m pointing the relay as first cause of the problem...see Sean´s comments... 👍 👍
 
Pretty-sure that the VBoost has some function in its controller or the relay for the fuel operation. Sean will know.

There's a yellow wire from the VBoost servo motor and the fuel pump relay which go to an ignition coil and the ignition control unit. That appears to be for 1990-'03 models.

On the '85-'89 models the wire is red/white and runs from the fuel pump relay and the VBoost controller to the ignition advance unit.

View attachment 89678
View attachment 89679
Sorry *fire-medic but in my previous answer I only had "the first line of your comments"

The Ignition Advance Unit is "Inside" of the Ignition Control Unit(CDI),isn´t it?...
Buff,I will take a look at the Vboost Control Unit...see how it looks inside.
 
The Ignition Advance Unit is "Inside" of the Ignition Control Unit(CDI),isn´t it?...
No, this is a separate unit which is located near the headstock on the LH side. The easiest way to find it is to follow the vacuum tube up from the LH front intake.
The unit changes the manifold depression into an electrical value which the ICU uses to adjust the advance.
 
No, this is a separate unit which is located near the headstock on the LH side. The easiest way to find it is to follow the vacuum tube up from the LH front intake.
The unit changes the manifold depression into an electrical value which the ICU uses to adjust the advance.
Thank you *MaxMidnight,Pressure Sensor according to the manual,isn´t it?..I will check how it works according to the manual..
I will foward the investigations of both parts.... 🍻
 
Thank you *MaxMidnight,Pressure Sensor according to the manual,isn´t it?..I will check how it works according to the manual..
I will foward the investigations of both parts.... 🍻
Pressure sensor ok...(well,looks like it was not" firmly attach" ..the diference now is that,I can disconect the servomotor(keep the Vboost always open..)nad the fuel pump does not "run all the time",when I start the enguine...I will made a test ride....
 
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