Buying first vmax but v boost dont work

[muscles68]

Hi new here and this week buying a 2003 vmax off a friend it runs well just needs a tidy up. One thing he said is the v boost dont work but he rode it like it and said it was fine. My question is are they ok to use if v boost dont work. Also i read its possibly the controller there seems to be a few on ebay all around £200 mark used. Mines a 2003 model most ive seen for sale are 1995 1999 are the contrllers all the same?

 

[MaxMidnight]

Yes, they run OK but you do loose out on top-end power.
Alternatively you can run with open V Boost which will loose some low end power + you would need to close off the V Boost butterflies to balance the carbs.

Some fail because of poor connections inside the control unit due to dry soldered joints which can be repaired.

Rather than replace the VB control unit you could replace the Ignition Control Unit with an Ignitech which will not gives an adjustable VB but also a rev limiter +much more.

 

[muscles68]

Yes, they run OK but you do loose out on top-end power.
Alternatively you can run with open V Boost which will loose some low end power + you would need to close off the V Boost butterflies to balance the carbs.

Some fail because of poor connections inside the control unit due to dry soldered joints which can be repaired.

Rather than replace the VB control unit you could replace the Ignition Control Unit with an Ignitech which will not gives an adjustable VB but also a rev limiter +much more.

Thanks for that so does the Ignitech go where the sqaure box controler is?

 

[Fire-medic]

I agree with Mr. MaxMidnight, it's worth getting an Ignitech for the rev limiter. The engines live longer if you're in the habit of stretching the throttle cables. Get the Ignitech if the VBoost cannot be resuscitated by re-soldering the leads from the plug into the circuit board.

1985-1989 are a 5 wire two pick-up ignition while the 1990-'07 are a single ignition pick-up digital system. Neither has an OEM rev limiter.



The Ignitech goes where the OEM ignition box fits, behind the steering head.

 

[muscles68]

I agree with Mr. MaxMidnight, it's worth getting an Ignitech for the rev limiter. The engines live longer if you're in the habit of stretching the throttle cables. Get the Ignitech if the VBoost cannot be resuscitated by re-soldering the leads from the plug into the circuit board.

1985-1989 are a 5 wire two pick-up ignition while the 1990-'07 are a single ignition pick-up digital system. Neither has an OEM rev limiter.

View attachment 90661View attachment 90662

The Ignitech goes where the OEM ignition box fits, behind the steering head.

Thats fantastic info thank you