How do I expand the spring that goes around the clutch so I can put the side cover back on?

Look inside the housing and you will see where the brake spring attached. Flip this part and it should unlock it

If the spring has a long section that hooks around the pedal just use a screw driver and place the blade under the spring and on to the pedal arm and lever the spring back until the hook bit goes over the pedal .

I had a Tri Z, and every time it sat the clutch stuck. I'm not exactly sure why your clutch won't disengage when you tighten the springs-I do know that the springs MUST be tightened to where the bolts bottom out for it to work. I do also suspect that running it with the springs loose has burned what was left of the clutch. The basket and inner hub grooved could be an issue. It would depend on how bad it's notched. They will normally operate fine with some notching. Filing down the basket is not recommended-you would have to take the exact same amount of material off each finger of the basket for it to work properly. I've done this only to get it running while waiting for a new basket and drive hub to arrive.
The main thing now is to get the clutch to disengage w/ the lever. Take the pressure plate off, and watch for the lifter to mave about 1/8" when you pull the lever. If it's not moving, or is too high, remove the lifter, the round ball behind it and the engaging rod out of the hollow clutch shaft. A small magnet tool works well.It may have gotten past the cam on the cable end of the system. With the rod out, turn the cable actuating lever back to the end of it's slack and reinstall the rod,ball and lifter. You should be able to turn the cable actuating rod with your fingers and watch the lifter come up. You can feel when the rod is in the right position on the cable arm-it should bottom out and lift within the working rotation of the lever. So if you get that working, put what's left of the clutch back together, tighten the springs and make sure it works.You will at the very least need to replace the friction plates in the clutch. The steels should be checked for warpage on a flat surface. If you can get .002 feeler gauge under the warp it's too far gone and they should be replaced as well. Most Yamaha clutches have a first and last friction plate that's a different part number when you order them, be sure to check that when replacing the plates.I'd get new springs as well, they're cheap. Good luck!

I believe the arm is on top of the case on the left hand side attached to a shaft that goes into the case. It also may have a bolt in the side of the case below the arm that has a machined shoulder on it to retain the shaft from pulling out. If it does, remove it.If this is the way it's set up, it actuates the clutch thru a rod that goes all the way across the motor inside the hollow shaft that the clutch is mounted on. I don't have specific experience to the 250 KX, but I've been in the little ones and that's the way they're set up. So here's what you do-
Drain the gear oil and remove the round clutch cover on the right side of the bike. Remove the 5 or 6 washered bolts and the springs from the clutch pressure plate. Remove the pressure plate and you'll see the clutch lifter-it's a short rod with a flat bearing on it located in the middle of the clutch shaft. Remove it and using a small magnet tool go inside the hollow shaft and retrieve the actuating rod. There may be a ball bearing with it as well, although I don't think there is in that bike. Anyway, don't lose it if it has one and pay attention to which end of the shaft goes to the clutch arm. You can now replace the arm. When your putting it back together, rotate the arm with your fingers and make sure the lifter is moving up and down before you put the pressure plate and springs back in. Good luck!

That's exactly what that is. We call it a "derby cover". It's held on by four screws. Take this cover off. There is a locknut and small spring that is behind the cover. This holds the clutch adjuster. Just put it back in the hole. The plate is sealed by a "quad ring". This is an O-ring made of square material. Just replace the quad ring and it should solve your leak. You can use some thick grease to hold the quad ring in place while you replace the cover. Don't forget to put the locknut and spring back in first.

Good Luck
steve

To change the clutch cable on you '79 Sporty, you'll have to take the outer primary cover off. To do this, you'll have to drain the oil from the primary, take the left side foot peg off, and loosen the primary chain adjuster on the bottom side of the primary. Loosen the locknut and use an allen wrench or hex key to screw the adjuster bolt downward.

If you need to know anything else, drop me a line at [email protected]

Then, remove the large "plug" towards the rear of the cover. Inside, you'll see something that looks like a nut but with no threads in it held in by a small spring. This the the lock nut, remove it. Below it is what looks like another nut with a slotted adjuster bolt sticking out. Remover the bolts from around the primary cover and break it loose from the engine. While turning the adjuster screw at the rear of the cover inward, remove the cover.

The cable connects to the cluch release mechanism. By turning the "link" downwards, you can disconnect it from the mechanism. Notice which way the "link" in attached to the release mechanism. Take the "link" off the end of the clutch cable.

Break the lock nut loose at the threaded cable adjuster on the outside of the case and screw the adjuster all the way out of the primary cover. Disconnect the cable at the handlebar lever and your cable is out.

Reinstall the new cable in the reverse order. When replacing the outer primary cover, make sure you use a new gasket on the cover as well as on the foot peg boss. The "foot peg boss gasket" is very important. You'll see an aluminum boss with a threaded rod sticking out of it that holds your left foot peg on. There is a round gasket that goes over this threaded rod and seals against the boss. If you leave this off, your bike will leak oil around this threaded rod when your foot peg goes on. Make sure you specifically ask for the "foot peg boss gasket" when you buy the new primary gasket. It's just a round gasket a bit larger than a quarter.

As you put the primary cover back on, there is a spring on the primary chain adjuster. Part of the spring is in the primary cover and the other part is in the engine. You'll see how it goes in. There is a large stud in that area that the outer primary cover slides up on. Adjust the tension on the primary chain by removing the "plug" at the top of the primary cover. You want 3/4" to 7/8" up and down play in the chain with the engine cold.

On the adjuster, as you're installing the outer cover, turn the ajuster screw back into the clutch release mechanism by turning the screw backwards. Once you have the outer primary cover completely installed, you must adjust the release mechanism. Adjust the screw inwards until you feel a resistance, then back the screw off about a 1/4 to 1/2 turn, insert the "lock nut" and spring, and install the "plug". Then, using the cable adjuster on the outside of the cover, adjust the cable. Add oil.

It is an pretty easy fix. Remove the right case cover and then loosen or remove the bolts that are compressing the clutch springs. Now slide the push rod 1/4" into the engine from the left side. Remount the lever assembly into the casing and put the casing back on. Now re-tighten the springs and put the right case cover back on. Re-fill with oil. All fixed.

A “very helpful” rating for this answer? Thanks!

That metal band you see which is preventing you from putting on the cover is part of the chain break mechanism. You were suppose to disengage the break before taking off the cover (I did the same thing). To get it back together you need to disengage the break by a tricky procedure and that will make the band diameter larger so it fits over the clutch. To force the band open, you need to first place the cover over the two bolts that hold the bar. As you already know, the back of the cover will not be able to fit over the clutch. Now in this angled position, bend (force) the break lever down (gray thing on top) until you can force together the sproket in the cover onto the mating pastic fitting built into the break lever. Now you can use the break lever to force down the internal spring and open the metal band. That will expand the stainless steel band and it will fit around the clutch. If you now push down on the back of the cover it will snap in over the clutch. Once you see how it is done, it is not so hard, but it is tricky because you are forcing some of the parts slightly out of position to get it back together. .

I used applman08's solution. A few pointers:
0. This problem occurs when you take off the side cover while the brake is set. So after you fix this, don't do that again.
1. When removing the clutch, place the screwdriver in the notch next to where it says "off" and tilt the screwdriver down so that when you strike it you are applying a clockwise shock force that is almost horizontal (assuming your 455 is on its side).
2. DO NOT remove the spring! There is a plastic housing that basically holds the brake mechanism in place (secured by 4 screws). If you take that apart, and then take out the spring, you will be learning how the brake works and spending some time compressing that spring and getting it back in. You'll have to come up with something clever to get the spring in depending on tools available.
3. Going back to 1. - get that clutch off, put the side cover back on, getting that brake lever lined up with the very-difficult-to-grab three-toothed mechanism for engaging the spring. Tighten down the side cover, or hold it snug with one hand while you lever the brake handle with the other. You will hear a satisfying snap as the braking mechanism (with the spring I told you not to mess with) resets.
Note: You can probably reset the braking mechanism by manually turning that three toothed gizmo but it's really hard to grab and the brake handle fits it perfectly. The key is you've got to turn that about 60 degrees.
Good luck, this was an annoying problem.

IF THE ROLLERS DON'T TURN AND MAYBE YOU HEAR A CLICKING NOISE FROM THE LEFT SIDE OF THE PRINTER, THERE IS A SPRING CLUTCH INSIDE THE GEAR AT THE END OF THE SHAFT GOING TO THE SWING ARM. I FOUND THAT SOMETIMES GREASE GETS INSIDE AND CAUSES THE SPRING TO SLIP INSTEAD OF GRIP LIKE IT SHOULD. IF YOU'RE VERY CAREFUL, YOU CAN TAKE OFF THE LEFT SIDE COVER AND LAY THE PRINTER ON ITS RIGHT SIDE (LEFT SIDE FACING UP). THEN REMOVE 3 OR 4 SCREWS AROUND THE GEAR ASSEMBLY AND LIFT THE ASSEMBLY STRAIGHT OFF THE PRINTER. TO GET TO THE SPRING CLUTCH, YOU'LL HAVE TO MOVE A COUPLE GEARS OUT OF THE WAY (REMEMBER HOW THEY GO BACK OR YOU'RE SCREWED - AND WATCH THE TONER ARM SPRING AS WELL). REMOVE THE PLASTIC C-CLIP ON THE END OF THE PICKUP SHAFT AND LIFT OFF THE CLUTCH GEAR. PULL THE GEAR APART AND WIPE OFF ANY GREASE FROM THE INNER SURFACES WHERE THE CLUTCH SPRING SITS. REVERSE YOUR STEPS TO PUT IT BACK TOGETHER.

--SORRY, MY CAPS LOCK DOESN"T WORK AND I DON'T FEEL LIKE HOLDING DOWN THE SHIFT KEY TO TYPE ALL DAY.