If you haven’t heard, the accelerator pump has been redesigned for ’01 for the YZ (and the WR too I’m sure). The few tests I’ve read or heard about reported an improvement in throttle response off of idle, this was attributed to the new pump design. Apparently most dealers have a partial fiche for ’01 part numbers. I called NCY and this is what I found: 3TJ-14293-40-00: 2001 Accelerator Pump Cover 3TJ-14293-40-00: 2000 Accelerator Pump Cover (they must be identical) 5BE-14940-18-00: 2000 Pump Diaphragm (STD, options 15, 17, & 19) 5JG-14940-07-00: 2001 Pump Diaphragm (STD, options 06, & 08) I tried to order one but it isn’t available yet. I plan on buying this part (heck, its only $15) when it is available to see what the difference is, I imagine the metal button is longer to reduce the stroke, and seeing what effect this has on my ’00 YZ’s throttle response. A poor man’s P-38?