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Trondyne

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Okay, so never having owned or rode a V-Max before I did some research first...

My understanding is that when you turn on the ignition -- turn the key on -- that you should hear the servo cycle...with a clear whining sound...

What I am hearing is not that sound.... Sometimes it clicks, sometimes it sounds a little like the servo but not loud and clear as I have heard on videos....and sometimes a hum sound....

This bike had at one point that T-Boost installed, and it has a little switch on the side of the front of the bike...

So, is there anything I can do to check if V-Boost is working, I don't notice anything at 5800 rpms...

Any thoughts?
 
The clicking is the fuel pump. Sometimes it needs to fill the bowls and sometimes they are already full.


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There are two types of sounds to listen for when you turn the key..
You have to train your brain to filter one out,, then test the other. At least that's what I do..:biglaugh:

One, is your fuel pump clicking away until your float bowls are pressurized. If they are already full, you may not hear the clicking.

The other is the V-Boost Servo (if it's working properly).
 
Pull the left scoop.

Check the vboost controller. Its a black box with two sets of wires/connectors coming off of it.

One connector is rectangular, with 3 pins. This plug feeds power to the controller.

One connector is round. It has 6 ports but only 5 are used. This feeds power to the servo motor.

If all this is plugged in correctly, remove an intake cover (chrome H under the carbs) You should be able to see in there and ID the servo. This will give a better idea as to what is going on.

If the bike has a t-boost switch, did you try flipping it? Some of those will turn vboost off at all times.

If everything is there but it doesn't work, I'd look at eliminating the wiring from the T-boost first and then moving on to diagnose components. Typically, the servo is good but the controller is bad. Try pushing/flexing the controller box. Sometime a bad solder joint is the only issue.

Sometimes a controller is totally junk. You can bypass a controller and wire up the servo to test it. You can wire up a DPDT switch and leave it like that for years if your lazy like me.
 

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Okay thanks for the info...

I can't say I have ever heard the servo doing it's thing... I was confused at first about the other sounds but now I get that it's the fuel pump...

The T-Boost switch doesn't seem to do anything regardless of the position -- up/middle/down...

When I have some time I need to have someone check out the bike who knows what they're doing... It seems to have lots of very low end torque but midrange power just seems to be ho-hum....

At least she seems to run reliably though and I'm getting used to the feel of the bike...

Thanks again for the info....
 

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