The infamous v boost switch

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69Z28RSSS

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Since I'm a new to me Vmax owner. 06 Max. What is everyone's take on the switch to have the v boost kick in at 3 grand instead of 6 ?
 
It sounds cool when the vboost is open at the lower RPMs
To me, the throttle feels more sensitive in the lower RPMs when vboost is open.
As these guys noted, dyno tests have shown that you lose power if its open before the factory intended spot (starts just below 6K)

I ran open vboost all the time for a few years. I just installed an aftermarket vboost controller with adjustable RPM levels. Its on the stock setting. I missed that feel when the bike jumps to life as vboost kicks in. Plus, i now have a fancy little LED to tell me its happening (as if I didn't know)
 
Since I'm a new to me Vmax owner. 06 Max. What is everyone's take on the switch to have the v boost kick in at 3 grand instead of 6 ?
Good move asking first, there's a lot of experience here that can steer you in the right direction. And save you a buck now and then. There was a T-boost unit in my trash barrel at one time.
 
Remember the all-important 'driving through the drive-in fun-factor.' The difference in the idle is always an entertaining observer topic among onlookers. Not that they notice the difference, but they notice the quality of the idle. Highly-important characteristic, that. Ride it slowly between the vehicles, give 'em plenty of time to absorb your bad-to-the-bone sound. No jizzing the throttle is necessary.
 
i never noticed a difference. at the time i wanted to justify the time and money spent but looking back it was pointless investment.
 
Remember the all-important 'driving through the drive-in fun-factor.' The difference in the idle is always an entertaining observer topic among onlookers. Not that they notice the difference, but they notice the quality of the idle. Highly-important characteristic, that. Ride it slowly between the vehicles, give 'em plenty of time to absorb your bad-to-the-bone sound. No jizzing the throttle is necessary.

OMG is this the truth. I had enhanced T-boost on my 94 (off/full-on/3k/6k) and had forgotten how radically different the idle is with the butterflies wide open. I have been riding my '86 this way for a year and a half and just got Vboost operable again. I swear 90% of the pleasure I've been getting out of this thing has been the way it sounds.

I cannot deny that you take a performance hit in the mid-range, but with the sexiest idle in the world and Vboost in full effect when it hits its stride at 6,000 rpm, I will be making this thing switchable in the very very near future. I cannot live without that sound. Period.

Interesting footnote: You always hear about "If you're not seeing the oil light, you're not riding it right". Well, I used to get it regularly on my 94 and my first 85 - never saw it on this 86. Until today! Coincidence or does Vboost working the way mother Yamaha intended it make that much difference? Interesting indeed. And here I thought the dadgum thing was running pretty good...
 
I liked it when it worked but I gotta say for me Stage 7 & Kerker 4/2/1 and the sound had me . Roll into a bike night and it was amazing to see peoples faces and how they reacted to the sound of the Beast I know about hurting performance but Damn that sound at idle was killer . Even had a Old school Pagan rider at a meet one night , he knew about the V-Max and it's performance . Too me it was funny because the rest of his group had no clue but he knew and appreciated all bikes .
 
From Canada Vancouver area, just ordered one of the vboost modules. This is my first vmax.
Got that ooooshi....... feeling two weeks ago, corvette goating me, thank GOD i was holding on tight
hit boost at i am guessing around 6000 rpm, after engaging warp drive, i swear i passed the star ship enterpise, came out of warp, heart pounding...........this is what this bag of bones needed. thank you
yamaha.
 
I recently installed one. I was riding with 3 grand setting, and I was digging it. Having it kick in at 6 grand is very, very accelerating!!! but there's something to be said for the 3 grand setting when jetting around town.
 
3K and 6K T-Boost installed by prior owner. Tried both settings, not seeing much difference so it might be disabled. V-Boost comes on at 6K, so I'm happy the way it is working.

OQC3xVM.jpg
 
I've found VBoost switches installed on one or another used VMaxes I've bought, but I never keep them installed. I'll either remove it or abandon in-place the switch, disconnected. I suppose it's fun to play-with, for the idle quality, but you can do the same thing by unplugging the round VBoost stepper motor electrical connector at wide-open when you turn-on the ignition.
 
I've got T boost with a lot of changes in my engine (cams, exhaust, carbs, head porting, intake, etc) . It is awesome. Much better than stock V Boost on a tuned engine, my switch is 3k/6k. The pull is awesome 3 grand up in every gear. I can understand why it would not work so well in a stock engine. All you need to do is think what a high winding tuned engine needs when it is modified to do more.
 
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Maybe I'm getting too old but I'm not sure if mine kicks in on It's own at 6000, but...at 6000 life is a blur. I couldn't imagine any extra boost.
That said mine has the toggle switch and at highway speed if I flip it forwards in notice better performance immediately.
Backwards it seems to run a lil rougher, but again at 6000 RPM my helmet is about to rip off.
Now I've ridden some fast bikes...drag raced and road raced...if there's something om missing at 6000 I admit I'm scared.
 
Maybe I'm getting too old but I'm not sure if mine kicks in on It's own at 6000, but...at 6000 life is a blur. I couldn't imagine any extra boost.
That said mine has the toggle switch and at highway speed if I flip it forwards in notice better performance immediately.
Backwards it seems to run a lil rougher, but again at 6000 RPM my helmet is about to rip off.
Now I've ridden some fast bikes...drag raced and road raced...if there's something om missing at 6000 I admit I'm scared.
Yes, at 6K RPM the VBoost is initiating the opening of the butterflies. You can find this in the Service Manual. They begin opening at 5,730 RPM and are fully-open by 8K RPM. See p.366 of the Service Manual http://vmoa.net/VMX12-Service-Manual01.pdf Use the .pdf page counter in the upper-left.

VMax VBoost operation RPM.png
 
Yes, at 6K RPM the VBoost is initiating the opening of the butterflies. You can find this in the Service Manual. They begin opening at 5,730 RPM and are fully-open by 8K RPM. See p.366 of the Service Manual http://vmoa.net/VMX12-Service-Manual01.pdf Use the .pdf page counter in the upper-left.

View attachment 85687

Nice that the actual initial starting 5,730 RPM point of the V-BOOST is presented here. Yamaha should have put a light on the bike showing V-BOOST when it is active. Maybe the word BOOST in amber...
 
There are many facts in the service manual overlooked by people. If the VMax owner takes the time to read the sections, your bike will benefit, and so will we, as you post helpful info you read. The front, with its multiple yearly supplements, takes some getting used-to.
 
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