V Boost RPM adjustment

[jmailley]

The servo works fine, I feel the boost but it's coming on around 6400. Do I have to take everything off(airbox & carbs) or can I just take the airbox off and get to the adjustments from there?

 

[Fire-medic]

Check for a loose cable. Find the service data here.

http://vmoa.net/VMX12-Service-Manual01.pdf

 

[desert_max]

There’s no provision for adjustment that I know of for when the Vboost comes on. I’ve had a couple of the controllers open and I’ve never seen a potentiometer in there. There are products on the market - or you could cobble something up that routes signals from two coils into the controller and fools it into thinking the engine spinning faster than it is. Other than that…

 

[MaxMidnight]

V Boost cable adjustment an butterfly synchronisation are described on pages
5-13 to 15 of the Service Manual.
There are devices such as T Boost that will open the butterflies earlier but IMO any benefit is in the head rather than on the road.

 

[[email protected]]

The airbox will need to come off, the carbs can stay.
https://www.vmaxforum.net/threads/how-to-adjust-vboost-cable.4361/

 

[sdt354]

Or, get an Ignatec ignition module and dial in the settings of your choice. You'll have the ability to change opening of the v-boost without taking anything apart, using the supplied USB cable. And you'll have several other useful features the factory didn't include, like a rev limiter.

 

[jmailley]

Thanks all. I'll let you know how I make out!