Help understanding our carb basics
Posted: Sat Jan 06, 2018 8:02 pm
1st time rebuilding carbs. I think I've figured out about 55% of how they work, so help me out a little on a couple things. so what it's come down to, the most difficult parts of this carb to figure out is the different jets. These two pics
https://mega.nz/#!jRAgWQLR!SP_Cwxde01je ... BZxecbaeF4
for the cb750 shows the main jet the one on the left, close to the pilot screw, whereas this one:
https://mega.nz/#!eUQBzJIK!NcAj17ORV_ui ... rdG09iNIi4
for the 81 cb650 has the main jet on the other side closest to the float needle jet, the one that catches the piston needle.
Now the carbs look the same, but the 750 uses the needle jet hole as the "secondary" jet, whereas the 81" 650 uses it as the main one which makes sense, as so should mine right? That would explain why I've not been able to pass any carb fluid through any 4 of these holes. So what... they just make them all the same for manufacturing costs and confuse noobs?
other than the jets, how does the pilot screw work? I see it is opposite a little hole in the throttle body. Does it connect to a channel going to that (useless?)first jet down the way?
WHAT IS THAT JET FOR!?!? excuse me. It's been driving me mad.
And please direct me to a source for a service manual specific to my bike if available. I've got Clymers and it just glosses over the carbs
Thanks
https://mega.nz/#!jRAgWQLR!SP_Cwxde01je ... BZxecbaeF4
for the cb750 shows the main jet the one on the left, close to the pilot screw, whereas this one:
https://mega.nz/#!eUQBzJIK!NcAj17ORV_ui ... rdG09iNIi4
for the 81 cb650 has the main jet on the other side closest to the float needle jet, the one that catches the piston needle.
Now the carbs look the same, but the 750 uses the needle jet hole as the "secondary" jet, whereas the 81" 650 uses it as the main one which makes sense, as so should mine right? That would explain why I've not been able to pass any carb fluid through any 4 of these holes. So what... they just make them all the same for manufacturing costs and confuse noobs?
other than the jets, how does the pilot screw work? I see it is opposite a little hole in the throttle body. Does it connect to a channel going to that (useless?)first jet down the way?
WHAT IS THAT JET FOR!?!? excuse me. It's been driving me mad.
And please direct me to a source for a service manual specific to my bike if available. I've got Clymers and it just glosses over the carbs
Thanks