Post by widehide on Sept 26, 2008 15:13:17 GMT -5
I found this on the GEKGO INTL. web site, might be valid for many scooter riders, I'm trying to figure out how to do this on my 257cc engine. this is for the other type Carb, not like mine but the theory is good.
Copied from Gekgo:
"To eliminate the automatic choke. Most of the GY6 scooter engines seem to come equipped with the Keihin style CV carburetor with automatic choke. In theory, this is a nice feature - the choke turns on by itself when needed and then shuts itself off - assuming it all works properly. Unfortunately, the automatic choke on these carbs seems to have a tendency to stick ON at times. As a result, the air/fuel mixture will be way too rich. This KILLS performance. There are a few ways to deal with this... one is to just remove and block off all passages in the carb for the automatic choke. An epoxy such as JB Weld can be used or one of the epoxy putties commonly found in automotive stores. If you primarily drive in warm weather, then the choke may not be needed anyway. However, if you drive in cooler climates, then you may need a way to richen the mixture so that you can get your engine started easier. Getting a whole new carburetor with a manual choke is one idea. Some of the newer Dazon buggies (go karts) are supposed to come with a manual choke carb on their GY6 engine. Also, a Mikuni TM24 carburetor can be used as a substitute, but since it's a slide carb then the throttle cable will need to be modified or replaced. The TM24 carburetor (or other manual choke carbs) also may require a spacer on the intake manifold to help the float bowl clear the engine shroud underneath. Another way to get fuel enrichment on a stock carb with choke removed is to add one of the plunger primers that are made for use on snowmobile or ultralight engines. This primer plunger can be pumped and squirt fuel into the intake and help with cold weather starting. A small 1/8" fitting needs to be added where the fuel is squirted into the carburetor or intake manifold. Also, a 1/8" hose needs to be added to supply fuel to the plunger primer. This supply line can be T'ed off the main fuel line or fuel can be tapped off the float bowl or however it works best on your application. Adding this plunger primer is not the easiest method but it does work, and allows the stock carb to be used in cold climates with auto choke eliminated. A more direct bolt in carb like found on some of the Dazon buggy GY6 engine may be the easier choice for these 150cc engines. Just check to make sure that it will fit your particular application. Not all carbs fit all engines! In any case, whatever you end up doing, eliminating the stock automatic electric choke can result in much more consistent performance. If your engines runs consistently well all of the time, then don't worry about changing the auto choke. However, if your scooter engine runs strong one moment and then feel sluggish the next, then it MIGHT be the auto choke sticking on. Just be aware of this as a factor in performance"
Here is a view of the Carb.
Copied from Gekgo:
"To eliminate the automatic choke. Most of the GY6 scooter engines seem to come equipped with the Keihin style CV carburetor with automatic choke. In theory, this is a nice feature - the choke turns on by itself when needed and then shuts itself off - assuming it all works properly. Unfortunately, the automatic choke on these carbs seems to have a tendency to stick ON at times. As a result, the air/fuel mixture will be way too rich. This KILLS performance. There are a few ways to deal with this... one is to just remove and block off all passages in the carb for the automatic choke. An epoxy such as JB Weld can be used or one of the epoxy putties commonly found in automotive stores. If you primarily drive in warm weather, then the choke may not be needed anyway. However, if you drive in cooler climates, then you may need a way to richen the mixture so that you can get your engine started easier. Getting a whole new carburetor with a manual choke is one idea. Some of the newer Dazon buggies (go karts) are supposed to come with a manual choke carb on their GY6 engine. Also, a Mikuni TM24 carburetor can be used as a substitute, but since it's a slide carb then the throttle cable will need to be modified or replaced. The TM24 carburetor (or other manual choke carbs) also may require a spacer on the intake manifold to help the float bowl clear the engine shroud underneath. Another way to get fuel enrichment on a stock carb with choke removed is to add one of the plunger primers that are made for use on snowmobile or ultralight engines. This primer plunger can be pumped and squirt fuel into the intake and help with cold weather starting. A small 1/8" fitting needs to be added where the fuel is squirted into the carburetor or intake manifold. Also, a 1/8" hose needs to be added to supply fuel to the plunger primer. This supply line can be T'ed off the main fuel line or fuel can be tapped off the float bowl or however it works best on your application. Adding this plunger primer is not the easiest method but it does work, and allows the stock carb to be used in cold climates with auto choke eliminated. A more direct bolt in carb like found on some of the Dazon buggy GY6 engine may be the easier choice for these 150cc engines. Just check to make sure that it will fit your particular application. Not all carbs fit all engines! In any case, whatever you end up doing, eliminating the stock automatic electric choke can result in much more consistent performance. If your engines runs consistently well all of the time, then don't worry about changing the auto choke. However, if your scooter engine runs strong one moment and then feel sluggish the next, then it MIGHT be the auto choke sticking on. Just be aware of this as a factor in performance"
Here is a view of the Carb.
