Can vboost can still be operational without the controller??

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anton73

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kinda stupid question but i still cant understand it. My 1988 VMAX doesnt have the vboost controller yet it does the servo noise on startup and i feel a pull when im in high rpms. What exactly does the controller do and is the vboost functional without it? HELP PLZ! (also the cylindrical plug for vboost looks like its coming out of my ecu and the 3 hole plug isnt plugged into anything)
 
Suggest you have a read of pages 7-59 to 63 of the Service Manual which explains the function of the V Boost system.
As far as I know, how the servo motor operates is determined by the controller therefore no controller = no servo motor operation.

Do you have the OE ignition unit installed?

Pictures of what you have would help.
 
Ignitech ignition doesn't require the controller . Perhaps you are hearing the fuel pump? The boost won't cycle w/o a controller when using the the stock ignition unit.

The controller gets vacuum and rpm data from the ignition and uses that to open/close vboost valves. It also "senses" the valve positioning.

Mark
 
Where ever the servo is when you unplug the controller that is where it will stay.
I haven't done it personally. But a couple people have told me they unplug it when it opens the servo on the start up test and it keeps it open.
Not sure if it's a benefit. I would think it would make the bike run ritcher.
 
Suggest you have a read of pages 7-59 to 63 of the Service Manual which explains the function of the V Boost system.
As far as I know, how the servo motor operates is determined by the controller therefore no controller = no servo motor operation.

Do you have the OE ignition unit installed?

Pictures of what you have would help.
Where ever the servo is when you unplug the controller that is where it will stay.
I haven't done it personally. But a couple people have told me they unplug it when it opens the servo on the start up test and it keeps it open.
Not sure if it's a benefit. I would think it would make the bike run ritcher.
Yea I have heard that too but i can see the cable for the vboost being pulled on startup as well as when it's in neutral and reved. Yet there is no control box
 
Suggest you have a read of pages 7-59 to 63 of the Service Manual which explains the function of the V Boost system.
As far as I know, how the servo motor operates is determined by the controller therefore no controller = no servo motor operation.

Do you have the OE ignition unit installed?

Pictures of what you have would help.
When I get home I'll send some pics. Thanks!
 
...but i can see the cable for the V Boost being pulled on startup as well as when it's in neutral and reved. Yet there is no control box
I can think of two explanations:
  1. There is a little person hiding somewhere on the bike that is pulling on the cable (it could also be a well trained or genetically modified primate - wave a banana near the bike when starting and if you see a paw stretching out you will know) or....
  2. You have a non OE ICU that controls the servo motor.
Those who wish to join the sweepstake to predict the correct answer should send their money to the usual address. :)
 
Hahahahaha
I can think of two explanations:
  1. There is a little person hiding somewhere on the bike that is pulling on the cable (it could also be a well trained or genetically modified primate - wave a banana near the bike when starting and if you see a paw stretching out you will know) or....
  2. You have a non OE ICU that controls the servo motor.
Those who wish to join the sweepstake to predict the correct answer should send their money to the usual address. :)
 
The main benefit of an open VBoost is the loping idle that drives the H-D riders crazy. They want it, but the VMax has it and they don't. They have their own distinctive idle. which they tried to copyright, but were unable to.

Pulling into any bike night on a VMax and having that open VBoost ba-bop-ba-bap-ba-bap at idle is sure to swivel heads and have people come see the bike when you park. No need to **** the throttle, just that distinctive idle as you slowly move thru the parting crowd.
 
Suggest you have a read of pages 7-59 to 63 of the Service Manual which explains the function of the V Boost system.
As far as I know, how the servo motor operates is determined by the controller therefore no controller = no servo motor operation.

Do you have the OE ignition unit installed?

Pictures of what you have would help.
 

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I see the vboost motor plgged in. You have an aftermarket ignition. If Ignitech, you can confirm by looking for a PC/VGA plug where a computer could be connected to.

Mark
 
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