Sticky Floats
I have a 1992 CBR600 F2 that I bought last summer. It was abused: trashed fairings, stretched chain and worn out sprockets. After I finally got the fairing and chain problem fixed it sat most of the winter. I live in Washington State so the winters are pretty much not a big issue, except this year we hit record lows in the single digits and my bike sat weathering it all. We finally got a break in the weather and when I went to start it up I had fuel just dumping out of the number one and two carburetor breather hose. I never really dealt with multi carb rebuilds so I am hesitant and don't have the money for a shop/dealer. Any ideas?
Michael Renshaw
Centralia WA Your problem is most likely that a float is stuck inside one of those two carburetors. The floats regulate the level of fuel in the carburetor float bowls. The bank of carburetors comes off the cylinder head spigots as a complete assembly, and you can probably access the two float bowls without having to disconnect the throttle cables. You will have to disconnect the fuel line, which is also easy; it connects to a barbed plastic fitting in the middle of the carburetor assembly using an expansion hose clamp, so you'll need a pair of needle nose pliers to pull back the hose clamp. Take off the float bowl covers; inside, the float is attached to a pivot mechanism that pushes a needle valve into its seat to regulate the fuel flow. Spray some carburetor cleaner on the mechanism and other components, then check to make sure the float needle moves freely. Dirt in the fuel is most likely the culprit, so it would be a good idea to change your bike's inline fuel filter while you're working under the tank.
Oil Change Intervals
I am using synthetic oil in a CBR600RR and do several track days every year. If running at high rpm for longer periods of time, how often should I change the oil in my bike? Should I follow Honda's schedule, change it every track day, or somewhere in between?
Jacob Young
Mount Airy MD The short answer is somewhere in between. High rpm at the racetrack breaks down oil quicker than normal street riding because of increased stress on the clutch and transmission as well as more combustion gas making its way into the engine's bottom end. A general rule of thumb is two or three track days between oil changes depending on the mileage, track, rider and oil used, but if you are mixing street and track use I'd recommend changing your oil after every track day so that the oil is at its freshest for the multiple cold starts and short trips that street riding entails.
Tuono Troubles
I own a 2003 Aprilia Tuono. I have 18,500 miles on the bike and have had a smile on my face every time I ride her. I have, however, had an issue for some time now with the bike not wanting to hold a charge. I keep it on a charger when not riding. The light on the charger never turns solid green. I tested the charger on my other bike and it works fine. I've put my third battery in the bike to date and still the same issue. I had the starter solenoid replaced one year ago, but to no avail. Two bike shops I've been to are puzzled as well.
Greg Londoff
St. Louis MO If the light on your charger doesn't turn solid green, that's an indication that the battery is never reaching a full charge. One possibility is a short in the wiring that is constantly draining the battery. Disconnect the battery and see if it will reach full charge, and while the battery is disconnected you can check for a short in the harness using an ohmmeter. If that's the case, inspect the positive wires from the battery to the starter relay, fuse box and ignition switch for wear or corrosion. If everything seems in order, check the regulator/rectifier by reading the battery voltage with the engine running. At about 4000 rpm the battery should show approximately 14 volts; much lower and there is a problem with the charging system. Some Tuono models have an issue with the connector from the stator overheating and causing problems; search for "brown connector" on apriliaforum.com for more details.
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