no 3rd gear?

a while back i took my gear box apart to replace the bearings and such. After i put it back together, i was having problems with the feel/shift of the ratchet setup, and kept taking the outer cover off to mess with the springs. So now i feel like it's shifting okay, but it seems like there is no 4th gear!? i took the plugs out of the motor and walked it down the street today, shift into first, neutral, 2nd, and when i go for 3rd it rolls like it's in neutral, i can walk it all day and nothing, shift up again and i get 4th gear. Sometimes it seems to also skip 3rd, especially downshifting from 4th, it seems to jump to 2nd. My first thought was maybe a problem with the cam and/or quadrant? FYI the bike is not running at this point so i'm only testing things either turning the wheel on the center stand or walking it around. both give the same result. :?:

The quadrant and spring position/adjustment seems the obvious answer. I had that problem the first time I did a AMC gearbox - took some fiddling to get it right but that's what it was.

Yep, you have to set the angle of the shift quadrant that has the socket for the ball/cylinder with the hole in it BEFORE you slip the camplate into it's proper place.

If ya got the cam plate wrong either cases don't go together or is just don't shift at all, so suspect pawl spring, the main trick being to get the pawl swing area spring legs parallel to each other with what ever reasonable gap to let pawl pivot w/o much worry to try to match factory measure. Another famous thing to check is primary chain/belt tension. I've had dog faces wear off and prevent full engagement but suspect you'd of seen-fixed-replaced that already. When right may be the sweetest manual designed by man.