Vboost or no Vboost

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The forum is great for help. There are many things in life that just defy logical thinking.

Having built alot of things over my life I ve been amazed at some of the things I've learned in the race shops I ve worked in. Nothing else is more fun than building someone elses 6 second drag car on their dime! :)
 
Matt,
No argument dyno's can lie, time slips yeah I guess you can fudge those too. BUT.... seat of the pants can lie just as well. I have no problem with your opinion. Your entitled to it, as am I and everyone else here. Just wanted to clarify that with you so you don't have any misconceptions of my opinion.

Actually, my ass (seat-of-the-pants) is the best judgement for me, where I look less for raw numbers, or time slips, but does the bike stir my soul. If it stirs my sould a little bit more, then it is good for me, even if it is completely in my head. (as long as I don't end up breaking shit while doing it lol... and if I do, it is all on me)

On that note, how do you get the V-Boost to stay open at all times? This way, I can try it out, and see how it feels to me.
 
Actually, my ass (seat-of-the-pants) is the best judgement for me, where I look less for raw numbers, or time slips, but does the bike stir my soul. If it stirs my sould a little bit more, then it is good for me, even if it is completely in my head. (as long as I don't end up breaking shit while doing it lol... and if I do, it is all on me)

On that note, how do you get the V-Boost to stay open at all times? This way, I can try it out, and see how it feels to me.

You can simply unplug the connection under the left scoop halfway through the cycle when the key is turned on. This way only opens it about 2/3 of the way on my bike. When I rebuilt my carbs I looped a large cable tie around the mechanism so that when I was ready to try it completely, I could just tighten it up and open them 100%. I then just reached in to cut it to remove it later. The 2/3 open still makes a noticeable difference though.

Matt
 
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Now it is all manual and what a difference it makes when you can pull it when you want it- any rpm in any gear anytime.
 

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It's an interesting discussion but let's get down to the nub of the gist; Does it make the bike more tractable or are we simply discussing an exponential increase in overall acceleration here ? And if we are, why ? This is thirty year old technology ffs. Yamaha have already gone through this with various other means of scooting fuel to multiple carburetors at a simultaneous pre - determined rev range. It has variously been named "EXUP" amongst other nomenclatures. Very innovative in it's time but nothing new in the overall scheme of things over the last three decades.
I kinda like the rush of my boost, (don't feel it so much these days) but it's a blast to my senses when the girl picks up her skirts and runs for the line. Isn't that what a VMax is all about ffs ?


Chris
 
With Stock carbs, opening Vboost give more grunt but only at partial throttle Openings.
Because it act like the butterfies were opening more and quicker.

The more the throttle is opened, the less effect it give, and at WOT you loose power till you reach 5000-6000 RPM (because airspeed in the intakes drops).
Above this threshold Vboost is doing is real job...

The best of both worlds is to have Voost opened all time at part throttle and above 5000-6000, and closed at WOT Under 5000-6000.
You can make it with IGNITECH TCI ;)

The opened vboost effect
 
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With Stock carbs, opening Vboost give more grunt but only at partial throttle Openings.
Because it act like the butterfies were opening more and quicker.

The more the throttle is opened, the less effect i give, and at WOT you loose power till you reach 5000-6000 RPM (because airspeed in the intakes drops).
Above this threshold Vboost is doing is real job...

The best of both worlds is to have Voost opened all time at part throttle and above 5000-6000, and closed at WOT Under 5000-6000.
You can make it with IGNITECH TCI ;)

The opened vboost effect
I still find it more effective at your fingertips.
 
Now it is all manual and what a difference it makes when you can pull it when you want it- any rpm in any gear anytime.


I may try this before I buy another boost controller or the Ignitec box to get my boost working.

How are the controls used in general when manual controled? I would guess closed below about 4-5k and open above that when wanting max hooligan power.
 
I may try this before I buy another boost controller or the Ignitec box to get my boost working.

How are the controls used in general when manual controled? I would guess closed below about 4-5k and open above that when wanting max hooligan power.

It is a bicycle clutch handle with cable hooked to the black box- pull it when ever you want to.
 
I know how it is done, I was curious how it is used.

Thanks,
Wayne Z
Not sure exactly what you are asking- it is manual and you can open it when you want to. You can keep it open at all times, you can open it partially, you can open it completely at any rpm at any time. Everyone will have their own preference as when they want to.
 
Not sure exactly what you are asking- it is manual and you can open it when you want to. You can keep it open at all times, you can open it partially, you can open it completely at any rpm at any time. Everyone will have their own preference as when they want to.

If you're doing a for instance a 1/4 mile run thru the gears, how do you operate the control and the clutch togetger?
 
So here's a question: has anyone actually dynod the difference between vboost and no vboost?

I mean on the same NA spec bike, not comparing the NA model to the neutered "rest of the world" bikes.

It doesn't seem to follow to me that simply linking two carbs together above 6000 rpm would make the difference between 98/100 hp and 145 hp.

If that were the case, all the head and cam work done on the vmax doesn't make any sense (financially for Yamaha) because the stock Venture engine makes (rated) 98hp.

I'm a bit suspicious that the neutered bikes had Venture spec cams and/or heads.

I'm interested because my 1200 Venture is going to get NA spec vmax heads, cams and 1300 carbs this winter but no vboost. I'm hoping for a 20-30 hp jump from the stock 98 hp. It's also getting a 33/9 final drive and a 2002 royal star Venture transmission (lower overall gearing than the Venture 1-3, 4the the same and deeper 5th over) to make better use of that extra hp.
 
145HP were for marketing, 130 is closed to truth

Quite likely.

Regardless, I'm wondering the difference between vboost and no v boost on a NA spec machine.

45 hp claimed diff for just (essentially) jamming a bigger carb on an engine doesn't seem to jive for me...
 

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