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I'm in the middle of doing the first valve adjustment and ran into a few things. While I was tearing it down, I noticed two vacuum lines on the left side of the motor that are plugged at the end, right in the vicinity of the fuel lines/regulator. The regulator also has a vacuum diaphram but no line hooked up to it. I've been an automotive tech for several years and am not used to seeing things like this, is it normal?
 

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Looking at the manual the lines should go to the air box if that's the ones your talking about.
 

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www.linerwiki.com If you need a manual.
Thank you, lots of good info on that site I never knew about. Going by the manual it looks like there is no vacuum applied to the regulator and those lines just hang out there, so all looks normal. Still very strange to me, but it runs like a raped ape so I won't argue.


Wingman,

Are these the two ports for balancing the throttle bodies?

Dave

Not 100% sure, they just go into the airbox.
 

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Wingman,

Are these the two ports for balancing the throttle bodies?

Dave
That would have been my guess too. But if they go into the air box then I have my doubts. But I am confused additionally by the descriptions given. In one description the vaccum lines end and are capped off near the regulator. In a second description now they go into the air box. If they go into the airbox, now I have my doubts that they are for balancing the TB's. Going into the airbox might be because they are for atmospheric air pressure sensors. I don't think they would put diagnostic vaccum lines in the airbox because that would require the gas tank to come off to balance the TB's, would think they do that with the bike running.
 

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Air pressure sensors.

Stratowart,

Looking at the TB balancing in the manual. Looks like you do need to take the tank off. There are two lines for the cylinder 1 and 2 air intake pressure sensors that connect to the air box. As you said. Looks like a T is put in the line to sync the throttle bodies I believe. You take the tank off hook it up then put it back on. I paid to get my throttle bodies synced.

Wingman,

I don't know why these hoses would be off but worth looking at.

Dave
 
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