What have I done?!?!

Alright, I just finished the complete teardown and rebuild of my 78 KZ650 D1A SR. Way too much work to list. Finally figured out my petcock way stuck and.... vvvrrrrooooommm!! On the first hint of a crank, she fired up. No smoke (at first), no sputter. She sounds GREAT! Here is the issue. Stuck in first gear, neutral light on... release clutch, she drives... in first with N light on. The slightest up shift to hopefully find neutral, lands me right into 2nd and locks up... clutch in to keep from stalling, I can up shift and feel 3rd, 4th, and 5th. and back down until I hit 1st and N light comes on, clutch out, she drives on. OK, so this brings me to the subject title here...

WHAT HAVE I DONE?!?!

Assuming I understand what you wrote (I'm kind of slow this morning), you're saying the transmission locks up in any gear but first? Or just in second?

I've been sitting here reviewing the trans assembly in my head for the last few minutes, and the only way I can see this happening is if the shift fork that moves first gear is either not moving, or out of place. That leaves the trans always in first gear, and when you shift to another gear it puts the trans in two gears at once, locking it up.

So, either you made a mistake when assembling the trans, or I totally misunderstood what you wrote

You understood correctly and what you say makes perfect sense. I did not take notice as to exactly which groove each fork came out of and went back in to, dumb mistake looking back. Considering I hit that "wall" 2 or 3 times while moving, what are the chances that I bent/damaged that fork? Maybe I should order a new one before I go back in there.

Where are you located? I'm fairly certain I have a set of 750 four shift forks laying around that I'm not going to use, and I'm pretty sure they're the same, but check kawasaki.com parts diagrams to see if 83 GPz750 forks are the same as yours.

Has anyone ever had this happen to them? If so, what was wrong and what was the damage?

More than likely there won't be any damage

The best answer I can come up with is that when you assembled the trans you got the low shifter fork outside low gear, that would disengage the shift fork from the shift drum, thus letting you shift into other gears and lock the trans up.


The key question is, did you test the trans for proper operation before you assembled the cases?