There's nothing wrong with the K&N jet kits. In fact they're actually made by and identical to the Dynajet jet kit. They do assign their own part numbering system, however, which makes things a little confusing, especially when stocking both the K&N and Dynajet kits (different numbers for the exact same thing). Personally, I prefer the Dynajet (or K&N) to the Factory kit. I stopped carrying the Factory kits several years ago as most of the kits looked old, right out of the box. The springs (if any) would be tarnished and the whole kit looked like it had been setting on the shelf (or under water) someplace. The Dynajet kits usually involve a little more than the Factory kits as well. I must admit though, that the Factory support is much better than Dynajet's.
I also find the name "Factory" to be a bit dishonest. The deliberate intention here was to confuse or deliberately mislead the customer into thinking that he was buying a genuine Kawasaki or Honda or whatever, while the "Factory" has nothing to do with any bike manufacturer's 'factory'. I can almost see them laughing their heads off when they came up with the name. Clever, but as I said, just a bit of a ruse.
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