PAIR Removal
2/15/2004
Start here to see how to remove the carbs.
Here’s what you’ll find on a ’91 under the rubber heat shield.
The vacuum lines from the two left intake manifolds “T” into a line to the PAIR system. You won’t need this line after removing the system. You can remove the “T” and just cap off the two lines. You’ll need them for syncing your carbs.
First component removed. I actually cut the hoses with a hobby saw to separate the parts.
You’ll need to remove the cooling hose connected to the right head to get to the bolts securing the second valve assembly.
You can see the bolt under the housing. This is why it must be removed. This is a good time to replace the O-ring between the housing and the head. This is the source of many coolant leaks on ST’s.
Everything removed. Evidence of coolant leakage.
Here are the parts you remove. See the large hose at the top of this picture? That connects to the aluminum air box at the top of the carb assembly. You’ll need to block it off with a cap or a plugged piece of tubing.
The entire PAIR system removed and the cooling hoses are reconnected. Nice clean look and far fewer locations for potential vacuum leakage!
What the engine looks like with the PAIR chrome pipes removed. I bought my block off plates from a site that no longer exists. These look like they might work.