Running lean; exhaust issues

[ERaney]

Hey friends!

This is my first actual post on here, but I've been around I here for a couple years now getting my 79 xs400 up and running.

Recently i did a bunch of mostly cosmetic work on the bike which involved taking off the exhaust. The guy i bought it from did a custom 2-1 exhaust. It ran just fine before with it, and i had it jetted properly. I replaced the exhaust gaskets when i put the pipes back on because they were leaking bad at the head.

Now no obvious leak at the head, but a small-ish leak at the joint to the muffler. She idles fine but i can tell its running hot and lean (pipes get real blue, and plugs look white) and died when i took it out around the block when trying to start moving in first uphill. Yup, had to push that puppy 1/4 mile uphill back home, all 125lbs of me Haha, im sure it was quite the site to see.

Would that small leak cause this? How can i fix it?! Please help a sista' out! This is literally the last thing i have to do on the bike and its driving me crazy. Ive been able to figure out all the other crap with this machine, but this is just stumping me!

 

[NewHavenMike]

Im sort of going through this process right now on my bike. Ive come to the conclusion that when you change "one of the three" you need to readjust/check all three. And by that i mean air, fuel, and spark.

 

[arfstrom]

Hot and Lean suggests you could -richen- the pilot screws. On a rebuild we suggest 3 turns, and after you get it with a carb balancing tool (2x4 with a long tube and atf in it. forgot the name, I have it in my garage.) That will get it rich. Lets see where that going to get us.
Tobie

 

[xschris]

manometer.