easiest way to check v boost

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cutlass79500

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whats the easiest way to check v boost? i noticed today when i turn the key on you can usually hear the v boost making its clicking noise for about 5 sec .today it just went click click the exhaust sounds differant at slow speeds smells a bit rich when your in traffic kinda bucks when you roll on the throttle at slow speeds 35 mph in 5th never did this before almost sounds like its dropping a cyl at idle . my next day off im gonna check the plugs intake boots . the past few days ive put over 100 miles in it mostly running 75 mph or so . its been about 400 miles since it was tuned and dynoed im wondering if maybe a clamp or somthong might be loose . i did drop from premium to regular to see how it would run gas mileage is better then it was makes no sense any info would be appriciated
 
Your Vboost servo is not working, it's stuck open, so that's why you smell gas and it sounds lumpy. Check your connections for the controller behind the left scoop. Unplug and spray with contact cleaner. Check your fuses as well. If you have no luck - your controller may be shot. ( unlikely ) So check for a bad wires may be possible. No it won't hurt to run it like that, but your gas miliage will suffer. It may be a idea to add some seafoam to help unburnt fuel deposits from sticking.
It could be a machanical so don't rule anything out.
 
thanks for the info. i figured thats what it was . have to trace it even farther it has a toggle switch with hi and low rpm . i also need to get the carb styx out i think one of the throttle blades is off a little at idle or idle screw . i bought the bike 350 miles north where it was tuned and dynod was 3 hrs north of there . will check into it on tuesday
 
Your Vboost servo is not working, it's stuck open, so that's why you smell gas and it sounds lumpy. Check your connections for the controller behind the left scoop. Unplug and spray with contact cleaner. Check your fuses as well. If you have no luck - your controller may be shot. ( unlikely ) So check for a bad wires may be possible. No it won't hurt to run it like that, but your gas miliage will suffer. It may be a idea to add some seafoam to help unburnt fuel deposits from sticking.
It could be a machanical so don't rule anything out.

thanks for the info. i figured thats what it was . have to trace it even farther it has a toggle switch with hi and low rpm . i also need to get the carb styx out i think one of the throttle blades is off a little at idle or idle screw . i bought the bike 350 miles north where it was tuned and dynod was 3 hrs north of there . will check into it on tuesday

Not unlikely. I've seen it before but it wasn't opening the Vboost. I guess it could break either way...:stickyman:
 
I was thinking on the most likely senerio...I have never read about the servo controller going kaputz. I didn't wanna see the guy going out and buying a new one if he didn't have to because of bad connection or wire.
 
My controller went south last fall... It was shorting out and randomly opening and closing the VBoost while cruising....

Replaced it with a MicroMachines adjustable unit....

Runs perfectly now.... :)

It should also be noted that my adjustment bolt on the VBoost cable was missing... Prevents the boost from opening all the way....

Replaced that as well....
 
Your Vboost servo is not working, it's stuck open, so that's why you smell gas and it sounds lumpy. Check your connections for the controller behind the left scoop. Unplug and spray with contact cleaner. Check your fuses as well. If you have no luck - your controller may be shot. ( unlikely ) So check for a bad wires may be possible. No it won't hurt to run it like that, but your gas miliage will suffer. It may be a idea to add some seafoam to help unburnt fuel deposits from sticking.
It could be a machanical so don't rule anything out.

I run 165 dynojet mains, 2 coils cut from the slide springs, no Y on the airbox, stock airfilter and Vboost wired open at all times (no controller or servo)
I averaged 38-42mpg pure highway mileage this weekend on a 950 mile trip running an average of 75-85mph.

My normal commuting mileage around Houston is 32-34mpg.

Point is in my experience at least that Vboost open all the time may hurt the bottom end response but doesn't hurt the gas mileage at all; at least on my bike.


Plus the lumpy idle is really cool sounding:eusa_dance:

Rusty
 
My controller went south last fall... It was shorting out and randomly opening and closing the VBoost while cruising....

Replaced it with a MicroMachines adjustable unit....

Runs perfectly now.... :)

It should also be noted that my adjustment bolt on the VBoost cable was missing... Prevents the boost from opening all the way....

Replaced that as well....
micro machines?
 
v boost is fine checked it today tightend all the boots pulled top off the airbox slides are fine. idle screws dont seem to make any differance .even tweeked the butterflys doesnt help . i didnt pull the plugs its not blowing black smoke or anything. need to get batteries for my lazer temp sensor and check the head pipes see if that will tell me anything. i did notice with the bike on the kickstand there is a drop of gas on the little black drain shifter side at the back of the carb closest to the seat. i made sure the screw that runs thru to it was tight . im beggining to think it might be because when they did jetted tha carbs they changed the air bleeds . the problem is only when you just barely touch the gas just enough to take it off the stops it gets rough its not happy at all .i dont believe its a clogged jet rpm is to low it should stumble to its off the idle circuit but its not. the only reason it bothers me is because when you take off from a stop its either all or nothing . :bang head:
 
My controller went south last fall... It was shorting out and randomly opening and closing the VBoost while cruising....

Replaced it with a MicroMachines adjustable unit....

Runs perfectly now.... :)

It should also be noted that my adjustment bolt on the VBoost cable was missing... Prevents the boost from opening all the way....

Replaced that as well....

I've looked at this item and a couple of others and they all seem to require a working Vboost computer.

Am I mistaken. The above states he REPLACED the OEM computer with this thing.

Thanks
 
I've looked at this item and a couple of others and they all seem to require a working Vboost computer.

Am I mistaken. The above states he REPLACED the OEM computer with this thing.

Thanks

The ignitech TCI that Dingy sells (which has a rev limiter included) can control the V-boost as well. You just have the purchase the extra plug.
 
after inspecting for mods by previous owners, I find none. After checking the wiring and then testing for a self test, i get none. I removed the air cleaner and it's box and I don't think the butterflies are stuck.

I must conclude that the computer is shot.

has anyone tried one of these:

the SASY http://www.enhancetech.com.au/ (very cool since you can adjust it on the handlebars...but useless if it does not replace the computer)

or this: (replacement guts...so to speak, you take the computer case apart and put this in)

http://www.ebay.com/itm/Yamaha-VMax...Parts_Accessories&hash=item27d02c04e1&vxp=mtr
 
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