Slow forward motion.

look and see if the drive belts are good and not cracked or worn. that is the most common problem i have found is belts worn out.

yes it is normal leave it alone if it isn't broke

Is the tractor moving slow or are the blades moving slowly? The belt on the mower blades may be slipping. If the tractor is moving slowly look to see if the transmission needs fluid.

If it's a hydrostatic transmission, I would have the transmission looked at. You may need to "purge" the system and check the fluid level.

The ones I've done called for the drive disconnects (the rod or lever which allows you to roll the tractor when the engine is shut down) to be in the flow bypass position. They also wanted the wheels off the floor, then the engine to be started, & the direction control to be worked SLOWLY to the front & rear positions 10-12 times. Then put the bypass valve back in its 'drive' position, fire the engine again & repeat the slow cycle of the direction control. The unit SHOULD be quieter now & perform better, but double check the oil level because expelling the air may have dropped it too low.

Some of those cadets (like those with the Command 20) have a compression release mechanism on the cam which is intended to make that engine crank easier but disengages once the engine fires up. It's a plastic part and is prone to break, resulting in a lot of strain on the starter motor. Interesting design, bad materials. Sometimes the engine will start anyway but this is not a good idea to operate this way. Pull the valve cover. Look at the motion of the exhaust valve when you turn the engine by hand. It will look similar to the motion of the intake valve if this part is broken. If it's working correctly, you should see the exhaust valve open slightly just after the intake valve closes. I'll attach a video to show what it looks like. Replacing the bad cam is a bit of work but not terrible.

MOST likely cause is a worn/failed drive belt. I'd replace that first - be SURE to use a Kevlar belt or you'll be repeating the repair in a very short time frame.

On the transmissions, there are bypass levers...make sure they are pushed in and not pulled out

Yes, there is a switch on the motion lever on the transmission, but there is also a relay switch that is taped to the fuse under the hood of the mower...if this goes bad, the deck will not come on

How do you disconnect the reverse safety switch on a cub cadet 2160... where is it located?

Cub Cadet Z Force 44 seems to be going quite a bit slower than when I first bought it. Drive belt seems to be fine.