[jeffd]

Sprockets - I prefer a 50 rear tooth as well, but this is with a doma pipe (broader powerband).

What else will break at 1500 miles? Not much - these things are pretty durable... On second thought - hopefully someone has put a metal screw, etc in the contact point (where aluminum meets the knuckle) on your kickstarter - otherwise, it can get pretty "floppy".

The PV cover increases volume of exhaust when the power valve is in the low rpm position. Think of it as giving yourself a gnarley pipe at low rpms without affecting anything at higher rpms (when the pv is in high rpm position). Given this, it will be more notice-able using a pipe with less bottom end to start out with (e.g. has more affect on doma, messico, gasgas, and fatty pipes over the gnarley). It improves throttle response and pull off the bottom end.

As far as jetting goes - given the same bike and rider - there are multiple ways to "skin a cat". I think Ian is missing something - it is that you can choose to use a richer needle (and maybe slide) and a leaner pilot, like a 38 (typical of stock gasgas jetting) Or you can use a leaner needle (and maybe slide) along with a richer pilot (like a 45). Both, LTR (for gasgas)and JD jetting (for ktm) use the latter method.

On edit - one advantage of going leaner on the needle and richer on the pilot (with proper idle and airscrew adjustments) is that you get greater sensitivity on adjustment of the pilot circuit. E.g. the air screw has greater effect and it is easier to dial in the jetting right off the bottom with quarter or a half a turn on the airscrew, etc.


jeff