I have a 89' 600 katana gsxr. the trans is stuck in 6th gear. Do I need to split the case to repair?

Most likely cause of not selecting a single gear is a bent shift fork.
Shift forks in motorcycles are what pushes the gears in and out on the shaft to engage them. Rough shifting or missing gears can sometimes cause them to bend.
Replacing them, however, requires removing and completely re-building the engine as the shift forks are right inside.
Alternatively it could be a damaged shift drum, but again it's a case of remove engine, split motor in half and have a look.
For a look at the gearbox itself, go to http://www.boltonmotorcycles.com/find/unit/8488
and select 'Transmission' and 'Shift Drum/Fork'

need more and clearer info

It sounds as if the clutch actuating rod has either failed or is not set up properly. Unless you know the complete history of a new (secondhand ) motor you should treat it as broken until proved otherwise. The problem with this type of bike is that younger riders use them as they are cheap and fast. So, they will go as fast as they can, but without looking after the bike. Probably the reason the engine was available in the first place.

the gear selector return spring is not an easy job had a go at changing mine on my gsxr had to remove the clutch plates and a few more bits had to come out before i could get to it so i left it the return spring is on the other side of the engine the right side and you need to remove the clutch casing theres a few more bits to remove but you should be able to see the spring when the clutch plate is out it is attached to the bar that runs through the engine from the gear selector to the clutch good luck with this also when i had an issue with mine and saw the work involved i decided to try and see if a new gear selector and foot pedal (a new unit ) on the left hand side as i hit something on this side and it worked fine like new might be worth a shot

sounds like 2nd gear failure,which is motor out and split to repair,go to your dealer and get them to test ride,

time to replace the clutches or use fresh motorcycle oil

I would say that a bearing froze up or something along those lines. So its not dead but you cannot split the case so finding and replacing it would be loads of fun.

yes they are the same carb.

the frame should be the same. the difference between the gsx and gsxr, is that one is a two stroke and one is a four stroke. the frames should be the same. what are you doing with these bike, first.......

Sounds like a bent shift fork to me. Not wanting to go into or between gears plus popping out of 2nd and making a knocking noise are classic symptoms.

Please rate this solution as a " FixYa " after the repair. Thanks!