How can we keep the rear wheel from coming off of the drive shaft?

Which of these does your vehicle have ?

Transfer Case - NVG 233-NP1 (Two Speed Selectable)
Transfer Case - NVG 136-NP4(One Speed Automatic)

The New Venture Gear NV233 is an electronic shift transfer, with the following three modes of operation, Two-wheel drive high range, Four-wheel drive high range, Four-wheel drive low range. The gear reduction for low range is provided by a planetary gear set. The floor-mounted shifter has been eliminated. A switch, located on the upper right side of the instrument panel, is used to select the operating range. The indicator lamps on the switch show the current mode of operation. When the four-wheel drive has been selected, the four-wheel drive indicator lamp on the switch is designed to turn on when the front axle has engaged.


Automatic Transfer Case
The single speed automatic transfer case system shifts automatically from rear wheel drive to four wheel drive when the transfer case shift control module (TCSCM) senses the difference in rotation speed of the front propeller shaft and the rear propeller shaft . Two vehicle speed sensors, one located at the rear output shaft area of the transfer case, and the other, located at the front output shaft area of the transfer case, send front and rear propeller shaft rotation speed information to the TCSCM.
When the front and rear output shaft rotations remain the same, the TCSCM sends pulse width modulation signals to the encoder/motor to keep the transfer case in rear wheel drive. When the front and rear output shafts rotations are different, the shift control module sends pulse width modulation signals to the encoder/motor to engage the transfer case into four wheel drive.
The system will automatically transfer a percentage of torque to either the front or rear axles as required to stop all wheel slip. When the front and rear output shafts rotations return to the same speed rotation, the shift control module sends pulse width modulation signals to the encoder/motor to position the transfer case back into rear wheel drive.
When the transfer case is engaged into four wheel drive, a lamp indicator on the instrument cluster will light. The automatic transfer case system is completely automated, no transfer case control button switching system is required.

Do you know what diagnostic trouble code's are ?

DTC C0300 Rear Speed Sensor Malfunction
DTC C0305 Front Speed Sensor Malfunction
DTC C0308 Motor A/B Circuit Low
DTC C0309 Motor A/B Circuit High
DTC C0310 Motor A/B Circuit Open
DTC C0315 Motor Ground Circuit Open
DTC C0374 General System Malfunction
DTC C0376 Front/Rear Shaft Speed Mismatch
DTC C0550 ECU Malfunction
DTC C0611 VIN Information Error
DTC C0895 Device Voltage Malfunction

Not OBD2 engine code's .

check the front drive shaft spline or "U" joint at the transfer case
splines on this shaft wear more quickly that the rear drive line
as the operation angles for the front diff are more acute that the rear shaft

when the rear is jacked up is it the wheels that turn only with no drive shaft movement. does the drive shaft turn when the rear wheels are off the ground. Does the drive shaft turn when you have it in neutral with you foot on the clutch and the rear wheels off the ground
The purpose of the questions is to establish whether the pinion and crown wheel in the diff are seized or if the main shaft and clutch shaft in the gear box are seized.

They are mainly used in front wheel drive, and many modern rear wheel drive cars with independent rear suspension typically use CV joints at the ends of the rear axle halfshafts, and increasingly use them on the prop shafts drive shafts.

No 4X4 switch on the instrument panel ?
Automatic Transfer Case
The single speed automatic transfer case system shifts automatically from rear wheel drive to four wheel drive when the transfer case shift control module (TCSCM) senses the difference in rotation speed of the front propeller shaft and the rear propeller shaft . Two vehicle speed sensors, one located at the rear output shaft area of the transfer case, and the other, located at the front output shaft area of the transfer case, send front and rear propeller shaft rotation speed information to the TCSCM.
When the front and rear output shaft rotations remain the same, the TCSCM sends pulse width modulation signals to the encoder/motor to keep the transfer case in rear wheel drive. When the front and rear output shafts rotations are different, the shift control module sends pulse width modulation signals to the encoder/motor to engage the transfer case into four wheel drive.
The system will automatically transfer a percentage of torque to either the front or rear axles as required to stop all wheel slip. When the front and rear output shafts rotations return to the same speed rotation, the shift control module sends pulse width modulation signals to the encoder/motor to position the transfer case back into rear wheel drive.
When the transfer case is engaged into four wheel drive, a lamp indicator on the instrument cluster will light. The automatic transfer case system is completely automated, no transfer case control button switching system is required.

Do you know what DTC'S - diagnostic trouble code's are ?
Auto part stores can't read these , your best bet take it to a qualified repair shop . One that has the knowledge an diagnostic equipment .
DTC C0300 Rear Speed Sensor Malfunction
DTC C0305 Front Speed Sensor Malfunction
DTC C0308 Motor A/B Circuit Low
DTC C0309 Motor A/B Circuit High
DTC C0310 Motor A/B Circuit Open
DTC C0315 Motor Ground Circuit Open
DTC C0374 General System Malfunction
DTC C0376 Front/Rear Shaft Speed Mismatch
DTC C0550 ECU Malfunction
DTC C0611 VIN Information Error
DTC C0895 Device Voltage Malfunction
Without proper factory service an repair info. an diagnostic tools

My two guesses, based on what you have written, are tire balance (or tires, period) or a wheel bearing.

This should help you a fair bit, it's not that big a job.
Instructions below found at:
http://motorcycle.justanswer.com/questions/1ayag-remove-rear-wheel
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In addition to the obvious of elevating the back of the motorcycle to get the weight off the rear tire, you need to unbolt the final drive from the swing arm and remove the final drive and rear wheel as an assembly. The drive shaft will come out with the final drive, not a problem.

Once you get the assembly off the bike, you can remove the axle then separate the final drive from the rear wheel and do what you needed to do.

When you go to re-install the drive shaft, you have to align the splines. Sometimes it is easier to put the bike in gear so the female splines on the intermediate shaft don't turn as you rotate the rear wheel to insert the drive shaft.
When you go to put it back together, just tighten the bolts that hold the final drive to the swing arm evenly in a crossing pattern until tight.

As an aside note, while you have it off, make sure you grease the splines on the end of the drive shaft and the splines for the rear wheel before putting it back together
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All the best, plainnash

If done what will keep the trans fluid inside the transmission tail shafts end?

Hello,

In order to remove the rear wheel, it is not necessary to remove the drive shaft. The first step is to get your rear wheel off the ground. The easiest way to do this is to put your bike on its center stand. However, not all bikes have center stands. If your bike does not have a center stand, you may want to buy a motorcycle lift (available from Pep-boys, or Harbor Freight). Once the rear wheel is off the ground, you can disconnect the brake linkage, and then remove the rear axle.

At this point there is nothing holding your rear wheel to the bike except for some meshing gears. Now you must lift and maneuver the rear wheel back and forth a little and eventually the final drive will work free. You will be able to slide the wheel toward the right side of the bike and then lower it to the ground.

In theory removing the rear wheel is that simple. In practice, the gears in the final drive can sometimes hold on quite tightly. This is particularly true if the rear wheel has not been removed for a long time or if your final drive is very worn. Usually being patient and persistent will pay off and you will be able to remove the rear wheel.

Sometimes it may prove easier to remove the entire wheel / final drive / drive shaft assembly first, and then separate them. In this case, the order of operations is different. Once you have the rear wheel off the ground, you can disconnect the rear brake linkage just as before. Next you can remove the four bolts that hold the drive shaft housing to the back of your crank case. Finally you can remove the rear axle and slide the wheel backwards the unmesh the drive shaft.

Regardless of which way you remove the rear wheel, it will be easier to put it back together by first attaching the drive shaft and final drive to the crank case, and then reinstall the wheel as described in the first method above.

Good Luck,
-Josh

if it is shaft drive like my 650 then remove all bolts holding final drive to frame loosen rear wheel spindle and remove wheel with the whole drive, shaft and all will come with it, then take out the spindle and remove the drive..