Vboost

[atp51]

Hey guys I got a question about the vboost. I just got a 89 vmax and there is a toggle switch on the left front side of the bike that the previous owner said changes the RPM vboost comes on at. I think it's a mod but not sure. I have no experience with vboost but I can't tell a difference no matter if the switch is up or down. Is the vboost a noticeable difference in power when it comes on? How do I tell if it is working? The solenoids are making a noise when the key is turned on so they should be working. I'm new to this so any help would be great thanks.

 

[tfisher65]

Normally T-Boost will change the V-Boost to kick in around 3,000rpm. You should feel a surge. Check under the left scoop, the after market controller should be located there.
Can you feel the V-Boost kick in at 6,000rpm?

 

[EAGLEPI]

Back in 88 and 89 I know Dale walker made a V-Boost override, it was like T-boost and other V-Boost mods except Dale's was either on or off.

 

[eatatjoz]

Sounds like it's a T-boost switch. It will drop the servo operation from 6k to 3k RPM's. But if you're not feeling it, I have to question the servo's operation.

When you turn the key on, do you hear a "whirr-whirr".

 

[atp51]

Normally T-Boost will change the V-Boost to kick in around 3,000rpm. You should feel a surge. Check under the left scoop, the after market controller should be located there.
Can you feel the V-Boost kick in at 6,000rpm?

I can't feel the boost kick in is it easily noticeable? I'll look for the controller tomorrow maybe it will have a sticker that will tell me something more.
Thanks

 

[atp51]

Sounds like it's a T-boost switch. It will drop the servo operation from 6k to 3k RPM's. But if you're not feeling it, I have to question the servo's operation.

When you turn the key on, do you hear a "whirr-whirr".

I'm not feeling it but I do hear the "whirr-whirr" it sounds a lot like the fuel pump on my R1. Is there any way to look at linkage or something while the bike is running that would let me know if it's kicking on or not? :confused2:

 

[gamorg02]

yea. have a helper. when you give power tothe bike each time u'll hear the 'whir.... whir.." thats the vboost controller self testing. the fuel pump sounds more like a fuel pump.

anyways when the whir whir happens look between the carbs. have a helper look there and tap you when it does that movement but rev the bike and see where it occurs.

 

[tfisher65]

You can also pull off the left scoop and look in between the carbs and make sure the cable is connected and moving when the servo self tests.

 

[KJShover]

Go slower through 3k and 6k rpm while riding. Its possible your just accelerating right through it.

If I'm heavy on the throttle I can barely notice the Vboost kicking in, but I've I'm just easing it through the RPM range I can definately feel it.

 

[tfisher65]

Go slower through 3k and 6k rpm while riding. Its possible your just accelerating right through it.

If I'm heavy on the throttle I can barely notice the Vboost kicking in, but I've I'm just easing it through the RPM range I can definately feel it.

Really? I can go WOT and feel it kick in at both 3K & 6K.

 

[KJShover]

I really can't, unless I slow it down. If I scream through the gears I can barely feel it if at all. If I'm doing a nitrous hit, can't feel it at all.

 

[Redbone]

I can feel it if I really feel for it but not normally under heavy throttle applications. As KJ said I have to slow it down to make sure it is still operational. :confused2:
It's harder to tell now that I have Sean's carb kit installed which keeps my attention more attuned to what I'm pointed at.:biglaugh:

 

[atp51]

Go slower through 3k and 6k rpm while riding. Its possible your just accelerating right through it.

If I'm heavy on the throttle I can barely notice the Vboost kicking in, but I've I'm just easing it through the RPM range I can definitely feel it.

That is the the case for me too. I took the cover off as suggested to make sure all was still hooked up and working it was. When I rode half throttle and watched for it I could definitely feel it open up. I never had a Vmax before and didn't know what to expect so I was looking for a real big boost in acceleration WOT
Thanks for all the help
eace out bike:

 

[88Vmax]

Can anyone give me a suggestion on my vboost. its been working and today i took my cover off to check my coolant and all. well i left for work an hour later and now its not doing the self test. i i unhooked battery a few times just to see if it would help and have cycled key about 10 times and nothing. Can anyone give me an idea on testing servo or the module? thanks

 

[naughtyG]

To test the servo just apply 12V directly to it.

Often the control module fails because of dry solder joints inside. Remove it, open it, re-solder all joints (you just need to re-melt the solder on each), then re-fit it and check.

 

[88Vmax]

hypatheticly thinking! could one ablly a 12v source to this with a pushbutton to have instant boost? the tboost is decent but sasy is what i want but $300?
Sis it possible just to run a switch with the factory vboost or unplug it period and run a button?

 

[alorio1]

Where on the socket going to servo would you apply the 12 volt source, what Im trying to say what color wires would you connect to on the socket ?

To test the servo just apply 12V directly to it.

Often the control module fails because of dry solder joints inside. Remove it, open it, re-solder all joints (you just need to re-melt the solder on each), then re-fit it and check.

 

[Rhoy Carter]

make sure the kill switch is in the on position to get the test to work

 

[glennkotr]

im a new v-max owner , just bought an 86 last week ( luv it) , what does the v-boost actually do ? how does it work ? im quite sure my bike is all original and totally stock , how can i get more out of this v-boost ?

 

[KJShover]

While idling and below 6k rpms, the engine is fed by one carb per cyl. Around 6k butterfies open up and will be fully open by around 8k rpm.

What this does, is feed the engine by 2 carbs per cyl.