Soft clutch 4-5 upshift only

[Spongelander]

So: Bike's back in operation; they replaced the transmission shaft and several gears. Those have grooves in them, and some of the dogs are worn. I'll post pictures. Stacy at Hillsboro Motosport did a great job tearing it down, replacing parts, and re-assembling. I went for a 200-mile ride after getting my bike back, and it is like a new bike.

Officially what happened is that the shift drum and transmission shaft bearing keeper plates had loose screws, allowing both to float, and parts to wear against each other. Those plates are held in by small screws for which the torque spec is 30 inch pounds (2.5 foot pounds). Threadlocker is specified for those screws, and my suspicion is that this step may have been missed.

I'm thinking this is an original assembly error (maybe break time intervened between operations) and I won the anti-lottery. I'm asking Mother K to help; we shall see.  I'm looking for lots of trouble-free miles now; I had the valves set to their outermost tolerance (and I'm pretty gentle to the bike) so that should be good for years.

I guess the lesson from this is - if the clutch play begins to vary - consider that things may be loose inside.  This will probably never happen to you.
Glad to be back!

[lather]

Glad it got fixed, hope Momma Kaw treats you well.

[zrx mitch]

I've been into Kawasaki transmissions on recently produced stuff, but not a C14 or ZX14, and am not understanding your parts description of these keeper plates. Was the cam on the end of the shift drum loose?  I'm really curious to see parts pictures and understand what happened.

[Spongelander]

I'm going to dig into my shop manual more, and post pictures soon. The description of the issue is:
"Found output trans shaft bearing keeper plate bolts loose. Also shift drum keeper plate bolts loose. This was causing trans shaft and bearing to float and allow gear dogs to come in contact at the wrong time. "
And the dogs on one of the gears I got back (5th?) have a flat spot at a 45 degree angle, measuring 0.2" or so.
More to follow!

[Kman]

So this makes sense if you look at shifting to 4-5 as a sequence of shifts with the 4-5 being the last of the sequence. As an experiment, a series of shifts 1-2, 2-3, 3-2, 2-3 might if replicating the condition described would rule out the 4-5 gears and point the finger back at air in the circuit.