which lines are the vacuum lines? the ones running off the carb?

 

Yes. They provide ventilation to the carb.

 

Yeah, there is two or three lines that come off the bottom of the carb and route down to the rear shock.

Check the ends to make sure they aren't clogged and follow the routing and see if there is any kinks/pinches or anything.

One of my vent lines got a little too close to the exhaust pipe before crossing over. It just melted closed. I just rerouted it a little bit.

 

I think i found the problem, there is a gold nipple/fitting on the top of the inlet of the carb on the motor side that allows air directly into the motor without going through the carb which would create the lean condition and rough engine running and what ever was on there must have fallen off when i was riding causing the random change... i covered it with my finger and the motor ran perfect. Should i use a rubber cover to seal it?

 

The thing im talking about is circled in red on the carb picture

 

*that* is a vacuum line.


The pink lines running down in that pic are VENT lines, not vacuum as a previous poster stated. But if they get closed off the bowl can have issues filling and cause fuel starvation.

So in other words check them all.

 

Yes, or re-plumb the emissions equipment it was hooked to from the factory. Either will fix the issue.

 

Yes, that should be plugged into your air injection system. there is a little pump that sits on top of your valve cleaner that it plugs into.

However, a lot of people bypass this system. Then they just cap this line. Just make sure to cap all the other lines of your air injection system.

 

Vacuum, ventilation, thanks for clearing that up.

In my head they are basically the same, meaning if they are plugged or not hooked up right, things don't work right.

 

I used a vacuum line cap from an auto parts store to close it up and clamped it so it doesn't fall off again, PO must have removed the line, took it out for a spin and it runs stronger then before with the new jetting set up ! pulls hard throughout the throttle range and will idle all day

Thanks for your help guys, I'm glad there are forums like this around with such knowledgeable people, even if it was just a simple fix lol

job done now time to ride