Reinstalling the Carburetor

Before we could get the carburetor back on the bike, there were a couple of other things we needed to take care of first. The biggest priority, since it is part of what holds the bike together is to get the isolator bolts back in place connected to the heads.


I started by applying a light film of anti-seize and snugged up the two bolts on both sides. The bracket for my steering damper is on the left side of the bike and connects via the isolator bolt, so I needed to make sure it was in place.


The torque spec for this is 60 ft lbs. I've been pretty good about making sure I'm torquing everything right, but since this is such a critical fastener, I wanted to be sure I did everything to spec. Fortunately, because I had the primary held up by the scissor jack, everything went together without a hitch.


I also needed to connect the rear motor mounts—one to each head.


With that out of the way, it was time to get the manifold installed. I replaced the beveled rubber gaskets on either side of the manifold. I was going to port match, but I decided to wait until I had the heads ported and polished next year. Since I didn't have a vice, and I didn't want to hand-hold the manifold while I was doing the grinding, I thought it was something that could wait for now.


Because the back side of the manifold bracket is slotted, I pre-installed those fasteners to make it a little easier to slip on.


This is a pretty tedious part of the job. It's hard to really get a wrench on these fasteners, so you have to approach this patiently—realizing there is no real quick way to do this. I tightened the fasteners a little, jiggled the manifold to help it seat properly, and then tightened some more—repeating this process until the fasteners felt tight. I won't know until I get it started up whether or not it leaks, but I've tried to be pretty careful to give the fasteners an opportunity to seat properly.


With the manifold attached and the carburetor off the bike, I pulled the plug at the bottom of the bowl and removed the main jet. Because I've added a lot more air with the velocity stack and the plugs looked they like were running pretty lean already—and by putting the muffler back together which should lean her out a little more, Steve and I thought it made sense to re-jet from the .068" it was currently up to .072". So, before I re-installed the carb I swapped out the main jet. After the break-in, when I take her back in for the "after" dyno, I'll also get a tune that should tell us if the bigger jet was what we needed or not.


I neglected to take a photo before it was too late, but I also reinstalled the throttle cables to the carburetor and tested to make sure the butterfly valve opened and closed like it's supposed to.


Connecting the carburetor through the back side is a long reach (so I had to add a short extension to my long ratchet extension to get the fasteners into the back of the carb. It also took a little coordination to do this job single handed (it would have been easier with a second set of hands), but you can do it without that if you're careful getting the first few threads started on the top bolt.


At this point I had to call it quits for the afternoon, but there's not really much more to do to be ready to start the break-in process. I have to get the breather bolts in place, get the battery put back on, the exhaust reinstalled (I'm hoping that goes on easier than the wresting match to get it off), the plugs back in, and get oil back in her. I think another afternoon and I'll be ready to fire her up.