Help with Backfire and is that starter noise normal? 75 cb360
- Thread starter keeleydavis
- Start date
mydlyfkryzis
当有疑问时踢你的敌人在生殖器上，你可以道歉后
It's old school making o-rings. Even at my company, we don't do it anymore. Some of our equipment uses 3/8" Cross section, 3 foot diameter o-rings. We get them folded up (coiled actually) in a plastic bage. 25 years ago, we just had a spool of the raw stuff and the cutting/gluing kit.
Not too many people really know how to make stuff anymore...shame, technical skills are slowly disappearing.
Not too many people really know how to make stuff anymore...shame, technical skills are slowly disappearing.
keeleydavis
Been Around the Block
Help with Backfire and is that starter noise normal? 75 cb360
Bike is running relatively good now. I can't seem to get the idle to go below a certain point without pushing the throttle forward. It's weird. I even loosened the throttle tension so that I know it's not sticking.
Is 5 1/2 turns out on the fuel screw too much? Anything less was running a little rich.
Bike is running relatively good now. I can't seem to get the idle to go below a certain point without pushing the throttle forward. It's weird. I even loosened the throttle tension so that I know it's not sticking.
Is 5 1/2 turns out on the fuel screw too much? Anything less was running a little rich.
keeleydavis said:
That suggests that the throttles are not in synch and you have to force them closed. Service the bike and bench synch the carbs.
5 1/2 turns is way too much. On your carbs are the screws on the air filter side or the engine side of the carb? On the filter side, the modulate air, so further out means more air = leaner. On most CV carbs that screw is on the engine side and it modulates fuel/air mix, so further out means more fuel. Take a few moments while the carbs are off to synch the throttles, to check where the screw is and to work out what it adjusts, air or fuel mix.
BTW, many hardware stores now sell metric fasteners. they are not th most cost effective way to buy hardware but sometimes they are the most convenient. Ours sells 4 and 5mm stainless cap screws which are perfect for float bowls. Take a sample screw to the store and match the diameter, thread pitch and length.
keeleydavis
Been Around the Block
teazer said:
The screw is on the engine side. Not sure I know what syncing the throttle means.
mydlyfkryzis
当有疑问时踢你的敌人在生殖器上，你可以道歉后
The left and right carburetor throttles need to be the same amount of opening. If one carburetor throttle is open more then the other, the problems you are having are likely.
If you look at the throttle linkage, in the center, there is a little screw, no head on it. It has an 8mm lock nut on it. This is what you use to get the carburetors so they have equal throttle.
It is easier if you have 2 vacuum gauges and 2 adapters for the manifold vacuum port. But you can get them equal, with a little work without it...Search this site for carburetor sync...lots of threads on it.
If you look at the throttle linkage, in the center, there is a little screw, no head on it. It has an 8mm lock nut on it. This is what you use to get the carburetors so they have equal throttle.
It is easier if you have 2 vacuum gauges and 2 adapters for the manifold vacuum port. But you can get them equal, with a little work without it...Search this site for carburetor sync...lots of threads on it.
Attachments
keeleydavis
Been Around the Block
I see this. Any advice on how the Adjustment works?
keeleydavis
Been Around the Block
I also have set of sync gauges I haven't used yet. Would this do the same as the throttle sync screw you just showed me?
mydlyfkryzis
当有疑问时踢你的敌人在生殖器上，你可以道歉后
There is a port on the side of the carburetor that allows vacuum measurement. You need an adapter to screw into this so you can hook up hoses for the gauges.
The you adjust that screw I pictured until both carburetors are the same.
Here's a vid that shows the correct way of doing it.
http://www.dotheton.com/forum/index.php?topic=28876.msg310249#msg310249
The you adjust that screw I pictured until both carburetors are the same.
Here's a vid that shows the correct way of doing it.
http://www.dotheton.com/forum/index.php?topic=28876.msg310249#msg310249
keeleydavis
Been Around the Block
mydlyfkryzis said:
Thanks so much. That immediately fixed my idle issue. I am getting a vacuum adapter from crazypj and will fine tune once that gets here. In my manual it says turn the air screw out to make leaner. Is that correct?
mydlyfkryzis
当有疑问时踢你的敌人在生殖器上，你可以道歉后
Not on the 360. The needle is leaner in (Clockwise), richer out (Counterclockwise).
Some carburetors, not ours, are air control, some are fuel control. Depends on the model. So it is confusing when generalizing sionce there are differences that can confuse.
However, when adjusting the mixture, you adjust for the highest idle speed, adjusting the screw in or out until the idle peaks. Whether it gets richer or leaner is almost irrelevant, as the right setting is not chosen by mixture, but by running. The best running speed at idle is also the best mixture.
Some carburetors, not ours, are air control, some are fuel control. Depends on the model. So it is confusing when generalizing sionce there are differences that can confuse.
However, when adjusting the mixture, you adjust for the highest idle speed, adjusting the screw in or out until the idle peaks. Whether it gets richer or leaner is almost irrelevant, as the right setting is not chosen by mixture, but by running. The best running speed at idle is also the best mixture.