V-Boost at 7K RPM

[98Redlne]

New V-Max owner here.

Picked her up last Sunday, a 2007 with 628 miles on the ODO.:eusa_dance:

One thing I have noticed is that my V-Boost does not kick in until 7000 RPM. From that point on all seems normal....or at least as normal as things get with the boost engaged

Is there some adjustment that will allow this late arriving boost to be lowered to the factory 6000 RPM?

I know that there is a kit to drop the boost point to 3K and at some point in the future I may do that, but at this point all I want to know is if this is normal?
If not what is the solution?

 

[KJShover]

New V-Max owner here.

Picked her up last Sunday, a 2007 with 628 miles on the ODO.:eusa_dance:

One thing I have noticed is that my V-Boost does not kick in until 7000 RPM. From that point on all seems normal....or at least as normal as things get with the boost engaged

Is there some adjustment that will allow this late arriving boost to be lowered to the factory 6000 RPM?

I know that there is a kit to drop the boost point to 3K and at some point in the future I may do that, but at this point all I want to know is if this is normal?
If not what is the solution?

Congratulations on owning the best year of Vmax!:biglaugh: and welcome to the forum.

You might need to adjust the linkage.

Have you held the bike at 6k to see if it comes in? The reason I ask is cause a couple of friends of mine said they had the same issue with thier Vboost and it turned out that they were just bypassing 6k and felt it cause by the time it was fully open they were around the 7k mark.

take a peek at the linkage when you turn on the key, you'll see the Vboost cycle open, close, then take up the slack from the cable. You just might have a little extra slack happening.

As for the Tboost, its a fun toy. but thats about it. I have one on my bike, but I 90% use it to keep the boost from opening when I'm out on the highway cruising to save on a little bit of mileage.

 

[98Redlne]

Thanks for the quick reply. I will check the linkage out when I get off of work tonight.

One thing is for sure. The V-Boost is a serious kick in the pants when it opens up. Gotta love that feeling. First time it kicked in I think I wet myself just a little.

 

[vmaxcruzer]

There is an adjustment on the cable that opens the butterfly's but doubt its been tampered with or out of whack since it only has 600+ miles. Most likely its you. If you ramp up the R's slowly they should start pulling at 6K, but if you slam the grip open it will ramp as fast as the solenoid can open them which may be around 7K. If you?re wanting to tailor your boost activation I recommend this unit. I?ve had it for three + years now and it works great.
http://micromachines.ca/

 

[vmaxcruzer]

Dammit!!! Shover, You beat me too it. LOL OK...I'm off to work.

 

[KJShover]

I'm thinking you might be expecting more of an instant punch at 6k. Here is how the Vboost works from a test ride report.

"At lower revs, the four 35mm downdraft carburetors have their own individual path to each cylinder. But once past 6000 rpm, a servo motor begins to open a butterfly-valve in the intake manifold between the cylinders, becoming fully open at 8000 rpm, allowing a pair of carbs smooth access to each cylinder bank of the V-4. Or so the theory goes. All I know is that the thing freakin' gets with the program at 6500 rpm and landmarks are transformed into kaleidoscopic blurs."

 

[KJShover]

Dammit!!! Shover, You beat me too it. LOL OK...I'm off to work.

LOL :rofl_200:

 

[sbeduckman]

Are the pipes stock? After putting Supertrapps on mine, the v-boost seems to kick in a little later. I've been told this is pretty common.

 

[98Redlne]

The bike is completely stock, although by the end of this winter I may have a different answer to your question :hmmm:


So I took her out for a spin last night with the intention of getting to know the V-Boost a little better. I think that KJS had it correct, I was rolling on the throttle a bit too quickly, sort of just snapping it open. By the time the servo moved enough to start feeling the boost, the bike was at 7000 RPM.

A little slower rate on the throttle and I can start to just feel the beginning of the boost at about 6250. By 6500 the truckload of torque shows up and awaaaaaay we go.

 

[gamorg02]

coudl be with the supertrapps but remember it begins opening and isn't fully open until 8k. i don't think u'd notice it 10 - 20% open. revving slowly i alwasy felt it about 7 - 7.5K so i'd say thats pretty normal. if ur curious, get a buddy to watch the servo while u rev the engine and see when it starts opening. i bet u'll find its right about 6k