Interesting note here. The KTM uses a 36mm carb. I think peak power, would be a bigger carb, atleast 38mm if not up to a 40mm. So might be the perfect power add on with this 300 kit. :-) The 125 uses the Keihin PWK 38S AG, maybe just a bolt on swap?
Found an article in an old dirt rider mag Jan 2008.
Dirt Rider mag modded a 300XC with the help from Dicks Racing to run in the Glen Helen 24hr. One of the mods was to the carb.
(from the mag)" The 36mm carb is great for for low-end response, but not stellar for mid-top power. To remedy this, Dick's Racing bores the carb in such a way that from 0-1/4 throttle the carb remains a 36mm. After that, it graduates to the flow characteristics of a 39mm carb. In order to compensate for the changing bore sizes, a Dial-a-jet is added which allows for precise jetting for max power without the risk of siezure"
"Dicks mods (carb, porting, compression, rad valve and FMF exh) broadens the appeal of the motor dramatically and it retains the good early response, but now hurls harder into the mid range and pulls like a missile on top"