Jet question (not jetting)

[kawabunga]

The pilot that was in the quad was a 48 "S" and when I went to trade in my jets I got a 50 with no "S" behind it, and it is longer than the 48. From the threads back they're identical, but the thicker part is longer than the 48. Is that the way it's supposed to be? Or do I have the wrong jet in. They're both Kehein and both fit, one's just longer though. Just wanna make sure I'm not gonna wreck anything.

[d3ktrix]

There both the same thing, doesn't make any difference.
I've used the long ones and the short ones in my bike.