Odd ball mod

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gundoc_iowa

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Okay I have an 04 Vmax. On the left side near the "scoop" there is a small metal toggle switch. I thought it might be for the tail light or headlight to cut off the power. That wasn't it. I thought it might be to disable the bike so if someone tried to steal it. Nope. Turns out it is a three position switch....and with the switch in the middle position the idle drops and seems sometimes to even sputter a bit. With it left or right however, the bike idles perfectly. Running down the highway if you flip the switch to the left or right position you can feel a difference as well....wtf?
 

ninjaneer

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try to flip the switch into different positions and note at what rpms the vboost hits. 0, 3000, 6000? i wonder if it's a t-boost or z-boost selection switch
 

tugla

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you can look from the right side of the bike and see the vboost servo move, so switch in a position and rev it up and like the guys say should see it move at different rpm's.
 

Rollie

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Try riding it and switching it at 3-4 K rpms . If there is a difference in sound & power , v-boost has been activated and you have a T-Boost installed . ( or the fan turned on , LOL ) .
 

gundoc_iowa

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Cruising down the highway at 5000rpm it makes a slight difference. But would these mods affect it at idle?! It audibly and on the tach drops rpms at idle. Maybe 100 revs.
 

Rollie

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Rode it into work, the Vboost kicks in at about 6500 like it always did. I don't get it.
So you flipped the switch to the right and boost kicked in at 6500 , and then you flipped it to the left and the boost kicked in at 6500 as well ? What about the middle position ? Same thing ?
 

Vendetta

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Cruising down the highway at 5000rpm it makes a slight difference. But would these mods affect it at idle?! It audibly and on the tach drops rpms at idle. Maybe 100 revs.
When the T-boost mod is done two diodes and a 4k resistor have to be wired in. Someone may have tried this mod and did it incorrectly.:confused2:
 

[email protected]

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Get in there and investigate. Takes about 1 minute of wrenching to remove the faux and scoop. Should be able to trace out the wires from there.
 

alorio1

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With the Vboost butterfly's in the open position, it does change the engine Idle. Its been so long since I had mine open, I can't remember if idle RPMs go up or down....
 

gundoc_iowa

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No matter what position the switch is in Vboost licks in at 6500 rpm. Doesn't make any sense. Something is causing a draw in the mid position.
 

RaWarrior

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Weird. "Old" t-boost things had to be spliced in and the resistors added as said above. The newer ones were plug-n-play, all that was contained in a little puck that had two "intercept" connectors, it just went between the factory harness and the servo controller. Those had switches for 3000-off-6000

Sounds like yours might be a constant boost/stock? Having the boost open at idle would make it way too rich and have a crappy(slow) idle.

Otherwise, yeah, dig into it and grab a picture of what you find attached to the switch.

Wonder if it's some sort of timing adjustment and not related to the boost at all?
 

Rusty McNeil

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With the Vboost butterfly's in the open position, it does change the engine Idle. Its been so long since I had mine open, I can't remember if idle RPMs go up or down....
Open Vboost at idle will lower RPMS and give it a really nasty/good sounding idle..

If your idle is set low with Vboost closed and you open the vboost at idle sometimes it will even die if you don't raise the idle......

I ditched my whole Vboost system except for the butterflies, wired them open so they could be closed for synching, have never regreted it one time...Vboost is cool but I think it's a little over rated part of the "Myth"
 
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