2000 yz426f

[Hunter_R.D.]

After about 4 hours of riding I went to shift from 2nd to first and it's like there was no first gear anymore. The bike will in gage in to 2nd gear and it will go into neutral but it's like there's nothing under 2nd gear. What could be the reason for this to happen?

[ScrewMx_Hd]

might be a stripped gear. time to split the cases, if you're not confident doing it take it to a reputable shop

[grayracer513]

Does the lever move to the first gear position in a normal manner, or does it feel as if it's against a positive stop at the neutral position?

[Hunter_R.D.]

When you go from 2nd down it feels like you can just push it to the stopping point and there's no engaging into neutral or 1st

[grayracer513]

Still a little unclear, but if the lever moves down from second as it does down from third, but there is no engagement of 1st, then there is a fault in the transmission that will require splitting the cases (probably a broken first gear wheel (on the output shaft).  If the lever shifts down from third normally, but then will not move to the next gear, that is, it feels stopped as it normally would if you were actually in first, then there is a possible fault within the shift linkage behind the clutch.  This would be repairable with the engine in the bike.

[Hunter_R.D.]

Still a little unclear, but if the lever moves down from second as it does down from third, but there is no engagement of 1st, then there is a fault in the transmission that will require splitting the cases (probably a broken first gear wheel (on the output shaft). If the lever shifts down from third normally, but then will not move to the next gear, that is, it feels stopped as it normally would if you were actually in first, then there is a possible fault within the shift linkage behind the clutch. This would be repairable with the engine in the bike.

It shifts from 2nd through all other gears just fine.