The carb parts warehouse site (
www.carbparts.com) hasn't worked yet today. I've tried it several times. Don't know if that's a temporary issue or not.
Have you been to CDave's site? It's referenced in the 'Every kdx rider should read...' post stuck to the top of this board.
Check out <tech tips> <needle decoding>. That will tell all about different tapers and such...hopefully to the extent you will no longer be '..at a loss' about it at all.
Some 'light reading'
HERE with special attention to what james dean has to say (forget that it's an RB carb thread. There is a
LOT of general carb info there that you could benefit from).
Something crucial to the understanding of needles: The L1 length is
not how long the straight section of the needle is!! It is the distance
to the point at which the needle is 2.515mm in diameter (known as the 'magic number').
This is critical when it comes to understanding tapers. Knowing the above, you can understand that a
slower angle (ex: 'A' or 1'00" taper) will have the taper start
higher (earlier) on the needle than a
faster angle (ex: 'C' or 1'34" taper) of the same L1. Because the angle is less on the 'A', it has to start sooner to have the same L1 as does a 'C' series needle.
This makes an 'A' needle richer-lower/leaner-higher and a 'C' needle leaner-lower/richer-higher.
Prepare to be amazed indeed. The proper 'C' series needle will knock your socks off! Yep..the CEL is a good place to start with the #5TV (oem slide).
If you have a specific question at a later time, please ask.
BTW...the numbers listed as 1'34" are 'minute-second' figures, or one minute, 34 seconds. There are 60 'minutes' in a circle, and 60 seconds in each minute of a particular arc.
So, a 1'34" taper (a 'C' needle) is roughly 1.5º An oem needle (a 'B' needle) is a 1'15" or 1.25º needle. An 'A' needle is 1'00" or 1º needle.
So...all your '..at a loss'es are gone, 'eh?