When i shift into gear my roadwarrior shuts off.

Foot on the brake before you shift
Lift up lightly on the shifter and wiggle
If nothing pull the center console and check the shifter to see what is in the way

I suspect riding it home in a high gear needed lots of clutch slip - could be you have worn the clutch plates quite a lot and perhaps overheated it.

If it is a cable operated clutch, adjusting it might restore some functionality but as the gearchange is "stuck", clearly some dismantling will be needed and it would probably expose the clutch parts for inspection.

.024. Plugs increase in gap over time. As much as .028 is OK. Awesome bike!!

The shift interlock is stuck most cars have a small hole near gear shift to insert the ignition key this should help to free up the mechanism.

clutch

Instructions

1.
The 2nd gear lockout is, a mechanical speed sensing mechanism. It doesn't care if the engine is running. You bypass it by scooting the bike forward, about 5-6 mph, while shifting the transmission into 2nd gear.
2

Stand on the left side of the bike, with the ignition "ON" and the transmission in neutral.
3 With your right foot on the ground, behind your left foot: place your left foot on the left foot peg, with your toe under the shifter; squeeze in the clutch.
*4.Scoot the bike forward about 5-6 mph, with your right foot, and shift the transmission into 2nd gear, with your left foot. If you accidentally go into 3rd, or some higher gear, you can easily shift back down into 2nd, without further movement of the bike.
5.To start the bike: Apply the choke if the engine is cold. Squeeze in the clutch and push the bike forward, both feet on the ground, about 8-12 mph. Release the clutch until the engine start
6
As soon as the engine starts: squeeze in the clutch and shift the bike into neutral.

You may have a shift fork or two starting to go bad. When a fork gets bent, it does not move the slider gear properly. When that happens, the slider's gear dogs don't engage fully into the slots cast into the driven gears. A rattling noise occurs. When full engagement happens you get the bucking. As time goes by, the shifting pedal will get harder and harder to shift. Then you simply can't get it into or out of a gear. The bike is 20 years old, parts are getting hard to find. Finding a shop willing to work on it can also be difficult to find. The repair will probably cost between $1000 and $1700. That's pretty much more than the bike is worth. The diagram below will give you an idea of how the shifting takes place. I wish I could give you better news. Please rate my answer. Thanks.

Kick stand up?

I have the same problem, its the screw in the gear shift, take it to kia they will replace it,