thank you F3 owners. I have a question, I put new fuel in the carburetor sync auxiliary fuel tank and now the carburetors are full of gunk.






is this normal? I don’t run this motorcycle yet. Should I just save my time with the carburetor setup and purchase a used EFI motorcycle? The carburetor on this F3 and the lack of available parts has made things difficult.

 

Nope, that’s not normal at all. You have/had some crud in your tank or lines somewhere. That much stuff would cause issues with an EFI engine too.

 

I just read the manual... The manual says for storage: drain fuel tank and carburetors, spray rust inhibiting oil. Replace oil/filter, ensure coolant is 50/50 to prevent freezing, pull caps and plugs and pour tbsp of oil into each cylinder, turn over, then replace plugs and caps. Place on blocks and not to store in sunlight. Of many.

This CBR is a 98, 24yrs and has probably had a mixed bag of backyard storage and garage and not sure if the petrol was ever drained from both the carburetor and fuel tank before storage or non-use. I honestly have had this for 2.7 years, and only ridden a handful and the gas must be horrible even with fuel stabilizer those say maximum of 6 months.

How do you drain the carburetors does this require removing them and then loosen the fastener from the float bowl?

 

It’s pretty simple. With the bike running, shut off the fuel. Let it run until the engine dies.
then on each carb, there is a drainage nipple on the bottom of the bowl. Place a rubber tube onto each nipple. The on the bowl there is a drainage screw. Loosen it a bit and the remaining fuel will drain into the tube. Catch it in a can or jar.
close the drainage screw when you are done.
that is pretty much it.
it doesn’t hurt to put some fuel stabilizer in the fuel tank not long before you do this. It will help protect everything if a little stays behind.

 

Need to go from top down and clean tank -> petcock -> fuel-lines -> filter -> carbs.
Use PEA-based fuel-system cleaner. Spray carb "cleaners" no longer work due to removal of chlorinated compounds

 

Okay got some of that today! Scrubbed the original tube gasket the previous owner used on the float bowls with Gum Out PEA based and gasket scrapper. Apparently this was making the float stick and causing the #3 and #4 to flood the carburetor and cylinder causing hydrolock. Dumped out the old gas out of the fuel tank, poured in Gumout Fuel System cleaner in the tank, put Gumout Fuel System cleaner in the aux tank for carburetor sync, and in the mobile 1.5 gal tank for when begin sync the Gumout Fuel System cleaner PEA based will circulate through the fuel lines and carburetor.

Question: Synching the carburetor, is pilot screw adjustment required? Do you need to use an RPM measurement on each cylinder and adjust all the pilot screws according to the RPM or does that mess up everything and where the manual says much better?

 

Use factory settings for pilots.
Then sync carbs.

 

The Clymer manual states after synchronization to use an rpm meter and adjust each pilot jet. Before synchronization adjusting the pilot jetting to the manual factory setting is enough to proceed then to synchronization?

 

Well, was able to bench synchronize and placing the carburetor on the intake tubes is difficult requiring loosening top and lower clamps, using lube to wiggle on, then fastening upper to lower clamps.
Started right up, seemed to be just fine with minimal dash light flickering. The next day had difficult idle and idle wandered off followed by shutting down every second similar to switching the off switch; then back on again. Possible rectifier, (previous owner apparently removed and wrapped with electrical tape).

 

Would anyone recommend this to synchronize with?