Under Dog
XS400 Addict
Hey everyone! Just joined up the other day. Glad to finally see a site for the XS400!
I purchased a beater '80 XS400 SG for my son to tinker on. When we picked it up, it didn't run. Well, we've been messing with the carbs lately. They are definitely clean now (all passages clear), but we're still having an issue I'd like to run by you all.
Just this afternoon we got the bike to idle off choke. Seems that while all jets and passages were clear, that our airscrew was pretty much closed off. It was set at 1 1/4 turns from lightly seated, but you could see the screw protruding in to the carb. I'm guessing the o-ring is pretty much shot and that 1 1/4 turns was equivalent to being screwed closed.
Right now I've got the screws at 3 turns out and the bike is finally idling on it's own! However, it's popping/back firing thru the carb pretty regularly. What's that likely indicative of? Still too lean and I should back the air screw out a little more? Or are we ready to move on to timing, valves, and other things?
What do you all think?
Thanks!
I purchased a beater '80 XS400 SG for my son to tinker on. When we picked it up, it didn't run. Well, we've been messing with the carbs lately. They are definitely clean now (all passages clear), but we're still having an issue I'd like to run by you all.
Just this afternoon we got the bike to idle off choke. Seems that while all jets and passages were clear, that our airscrew was pretty much closed off. It was set at 1 1/4 turns from lightly seated, but you could see the screw protruding in to the carb. I'm guessing the o-ring is pretty much shot and that 1 1/4 turns was equivalent to being screwed closed.
Right now I've got the screws at 3 turns out and the bike is finally idling on it's own! However, it's popping/back firing thru the carb pretty regularly. What's that likely indicative of? Still too lean and I should back the air screw out a little more? Or are we ready to move on to timing, valves, and other things?
What do you all think?
Thanks!