Hi, The rectifier of my honda CBR 1000f year of made: 1992 has just burned again. I had the old one replaced last november 2009. I want to know what the problem could be that the new one has burned. What does the colors black and white stand for. The old rectifier had 6 pins and the number of the rectifier was SH261-12 9.0.The replacement was ERS230 from the USA. There is a 7th wire that was tight on the outside of the rectifier.The colors from the pin were 1 red, 3 yellow , 1 black and 1 white. Thanks ....

The three yellow wires carry AC current from the generator to the rectifier. The rectifier turns this AC current into DC current and sends it back to the battery through the red and the black wires. I am not certain what the purpose of the 7th wire is on the new rectifier except that it may be used for thermal sensing of the rectifier - which would explain why it is mounted tight to the unit.
Of all the components that make up your Honda's charging system, the rectifier is the most likely to fail. The reason is usually excess temperature buildup - which causes the diodes inside it to fail. If you are running extra electrical accessories on your bike, this can cause the rectifier to overheat and die. Same thing if you frequently let the bike sit until the battery goes dead, the rectifier works hard to recharge it each time.
You may be able to extend the life of the unit by avoiding things that put extra strain on it, as described above. Also make sure there's nothing covering the cooling fins on the rectifier - or blocking airflow to it (dirt, that extra pair of gloves stuffed next to it, etc.).
Finally, there's one thing that will kill the rectifier instantly: connecting the battery cables backwards. That'll fry it every time.