HOw do I remove the roller on my Kirby Classic to remove hair build up

1. Make sure the belt is in contact with the shaft. 2. Remove the roller and clean the brushes AND the area that seats into the vacuum. If there is too much hair, string, etc. the brush may not roll. chances are the belt is probably not making contact. If it was you would smell rubber burning if the brush wasn't turning.

hair around ends of roller take off cut hair out

replace fan,belt and either clean ends of rollerbrush of string, hair, floss, etc or buy a new rollerbrush

An Ultimate G has lots of suction. If you turn on your vacuum and the bag immediately inflates - that is how you can tell if your Kirby is moving air (suction). There is a more modern brush that came out with the Ultimate G Diamond and the Sentria that has stiffer bristles that dig up pet hair better.

Another way to test the suction is to spread some baking soda onto a hard floor and vacuum it up - you can see how much suction your Ultimate G has, or take off the vacuum head and put on a hose and test the suction at the end of the tube.

Ways to increase your Ultimate G cleaning efficiency. Take off the vacuum head and remove the brush roller. Attach your hose attachment and **** vacuum out the head. Put on a new belt, and remove any hair and or string or threads that may be wrapped around the brush roller. Put the roller back on and on the ends of your roller you will see that the ends spin and have numbers on them. If your vacuum brushroll is original - you could have your bristles rather worn and so you can align the #3 on BOTH sides of the brushroller. This would be a good time to consider upgrading to the Sentria Brush.
Remove the bag, and replace with the CLOTH Kirby bag. It has the best filtration and it has the best airflow (which increases what you are referring to as suction). If you want to go the cheap route - at least get the paper Micron Magic with HEPA filtration (but it has slightly less air flow)
Remove the side mini emptor from the vacuum and check to see if there is anything clogged up on either the vacuum or the mini-emptor.
If your engine is running and inflating the bag and you replace the belt, the brush roller and to the cloth dust bag - your vacuum should pretty much run like a brand new Sentria Vacuum. Your vacuum system is outstanding, but may benefit from a little TLC if you have been neglecting it.

If it is a smell of burning rubber - most likely your vacuum belt is overdue for replacement.

At this point - remove the brush roller, remove the old belt, clean off your brush roller and remove any string or hair that may be bound up around it (usually around where the belt goes or on the sides), and put on a new belt. Your Kirby should act good as new if your bag is replaced at the same time.

If the brush roller has too much string and hair wrapped around it, many times the brush roller will not spin as fast as the belt is driving it and you will get that burning smell.

About once a month as I have German Shep dogs and cuz of the hair I check all the hoses to make sure they are free of dust bunnies. I also take the bottom plate off the roller, turn the lever to losen the belt and take the roller off. Clean/cut all the strings, hair etc off the roller , check the belt for cracks and burns and replace if need be. Put the roller cover back on, and reconnect the belt.

Then on the side of the machine where the bag attaches, this also slides out to clean. Sometimes heavier items will get stuck in there so that dog hair and larger items cannot pass to the bag and it clogs. This will make your suction very low.

Also a good check inside the bag compartment and clean with the attachment hose if need be, helps a great deal with ordor and dust when turned on. Especially if you have dogs/dander and hair. Ive also put carpet fresh inside my bag to keep the doggy ordor down.

Step 1: 
UNPLUG YOUR KIRBY VACUUM CLEANER. Before you go any further, take your time with this belt change. It's not that difficult, just a little different than most other vacuums. These belts are very easy to find on the internet. Step 2: 
You should be facing the front of your Kirby vacuum. The height adjustment lever will be on your right. Push the lever all the way down. Lift the light hood with your left hand. Turn theKirby vacuum belt lifter counter-clockwise with your right hand. Unlock the accessory lock. The accessory lock is located under the light hood. Move the lock to the left to disengage it. Remove the front of the vacuum cleaner.
Step 3: 
Turn the vacuum belt lifter all the way clockwise until the belt drops down. Unlock the roller plate by releasing the two latches on the rear. Pull the roller plate up slightly and then off.  
Step 4: 
Bend one end of the roller bracket just enough to remove the roller. Remove this end of the roller. If you need to replace the roller take it all the way out. Remove any carpet fiber, string, or hair from the roller with a scissor.

Step 5:
After you have removed the old belt, slide the new one back on the middle of the roller. If you're Kirby vacuum cleaner has a belt indicator light, the roller will have a magnet built onto one end of it. It's very important to install to install a roller with a magnet on the same side as the indicator light. The roller actually will only fit into the roller plate one way.
Step 6: 
Place the roller back in the roller bracket. Place the roller bracket back and lock it into place with the 2 latches. Rotate the vacuum cleaner belt lifter counter-clockwise. You should feel the the belt catch. Look inside to make sure the belt is being stretched onto the vacuum belt lifter. Reassemble the machine. After you have reassembled your Kirby, turn the belt lifter cockwise, releasing the vacuum belt onto the vacuum motor shaft.

PUll the roller brush out and make sure it turns freely by hand. If not clean all hair and debris off the roller brush, you might also remove the end caps (one at a time) and clean the hair out from the bearings underneath the cap (in the shop I use WD-40 and a non-serated pairing-knife). Replace caps they only go one way. If you can not free up the brush you'll have to replace it.

If the brush spins freely probably just need a new belt they stretch out over time.

When you turned the knob, did it turn easily or hard. If it was easy, then the knob part inside did not catch the belt. If it did turn hard, when you had the brush roll off, did you check the ends to see if they turned easily or not. if not, then replace the brush roll.