Wont shift into lower gears.

What happens in the other 3 gears? Do you just keep getting 4th, or do you have three gears worth of nuetral?

If the gear selector rotates through the positions for 3rd down to 1st then I would guess that the shift forks for 3rd, 2nd and 1st did not get engaged into the gear selector "cam". I am not really sure thats possible, though. He didn't simply leave a couple shift forks out, did he? No spare parts left over?

If the transmission will only shift up to 5th and down to 4th and then won't move any further (no neutral) then I would guess that the shift cam was installed incorrectly.

I don't know what bike your friend has so I can't give you any specific information. What I recommend, however, is to make sure that the transmission works before you put the rest of the engine together.......

Rod

when u shift the gears are you rocking the bike or are you keeping it still? transmissions just dont switch thru all the gears whith the bike still, they need some movement for the gears to shift properly.

try pushing forward a little every time you shift, other than that, i dont know.

You can't just run through the gears, you do need to bump the wheel back and forth as you run through the gears so they can line up and drop into the next one. If that fails to get you into the lower gears, there is probably something assembled wrong in the transmission. I don't know Kawasakis specifically, but on the Honda's the shift forks have a specific orientation and position in the transmission. You also need to make sure the shift forks engage the shift drum. The Honda transmissions also operate 4th and 5th gears with the same fork, if I remember correctly. If you didn't engage the other forks to the drum properly, only 4th and 5th gears would operate. On my Yamaha TT, the pawl mechanism on the end of the shift drum has pins. If you left out one of the pins or left out the wrong pin, it's possible that you wouldn't be able to shift down past a certain point. You're going to need to re-split the cases. I had a dealer assemble a transmission incorrectly once and the results can be quite catastrophic (this is why I do all of my own transmission service from now on).