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Old 08-24-2004, 06:45 AM   #1
neduro OP
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Joined: Jul 2003
Location: Colorado Springs, CO
Oddometer: 12,054
Neduro's Tire Changing Class

I debated on where to put this, and decided on Thumpers as we probably change our tires the most in here. Maybe it belongs in "The perfect line" but I've never been in there, and it seems to compliment Creepers excellent tube thread pretty well. So here goes.

It is a sad fact of life that motorcycle tires are a short lived affair, especially the knobbly ones that so many of us enjoy punishing in the dirt. During the summer, I change tires every other week, or at most, every third week (either putting new ones on or rotating old ones to utilize the sharp side of the knob). Because I do it so much, I have gotten better at it than I used to be, and I thought perhaps I could share that hard won knowledge.

These pictures happen to have been taken changing dirt tires, but the techniques shown here apply equally to street tires (well, maybe not the bits about rim locks and tube positioning). Later this week, I'll throw new tires on the GS and will document that as well.

Tire changes are not difficult. In putting together this set of directions, I changed both tires on my KTM at an unhurried pace, including shooting 72 pictures which took lots of time to pose, and including cleaning and greasing axles, checking brake pads, and validating spoke tension, in 54 minutes from first picture to last. I never used more than moderate force, did not break a sweat, and no curses were uttered.

A few things to have in mind as you approach this project.
1) If you are using force, you are doing it wrong. You are not stronger than the tire bead, and you don't want to be (broken beads mean wasted tire). If things are not happening easily, THINK about what forces you are putting on the tire and reposition things to align those forces with what you are trying to do. Like most things, tire changes are more a mental exercise than a physical one.
2) The devil, as they say, is in the details. A small change in position or etc can make all the difference. Pay attention to the subtleties of what you are doing. The single most important thing to notice is that the profile of the rim has a dish, or a low point, at the center where the spokes join. This dish is your friend- if the bead of the tire is resting down in the dish, it will be loose on the opposite side. If not, not even a 50 HP dirtbike can break it free.
3) Always look at the side of the tire opposite where you are working. All of the tension that you are working around is generated over there, not at the point where the tire iron is contacting the tire.

Again, these same approaches will apply to street tires as well, but I'll just focus on the pictures I have for now and worry about the others later.

Tire Removal:

We'll assume, for a moment, that you are able to get your bike situated so that the wheel in question is free, and are able to remove it, and so we'll start with the wheel off the bike and go from there.

I like to change tires using the new (or old) tire as a rest for the work I'm doing. The primary reason for doing so is to keep the sprockets and brake rotors off the floor and unbent. Lots of companies make nifty stands, but I've never been able to justify one given how well another tire works.

Step 1: Let air out. Remove the valve stem all the way, so that the tube can "breathe" as you change the volume of the tire through your manipulations. Tip: loosen the valve stem nut, if you have one, prior to letting the air out.

Step 2: Loosen (but do not remove) Rim Lock. Once the nut is loose, push the stem in to make sure that the rim lock has released its grip on the tire carcass. You may need to hit the stem with your socket hammer that you used to loosen the nut to get it to let go.

Step 3: Break the bead. On dirt tires, this is no big deal- I'm doing it here with my chaco'd foot. I can also do it by hand, if I feel like getting dirty. This is the biggest difference for street tires; we'll get to that later. If you're feeling uppity, turn the tire over and break the other side right now too, but chances are good that it doesn't really matter, that it will come free during your other manipulations anyway.

Step 4: Insert 2 tire irons, 4-6€ apart, 90 degrees off the valve stem and/or rim lock. You don't want to go opposite the stem or rim lock because then the bead can't seat all the way into the dish of the rim. You don't want to be anywhere close to them because they will make it harder to get the bead out. So, split the difference.

Step 5: Start working around tire away from initial "bite", inserting tire irons close at first and farther as the bead gets looser. Tip: if the tire is making it difficult to get the iron inside the bead, insert the tire iron just out from where the bead is crossing from outside to inside. It will be a very small bite, but it will be easy to get the iron in.

Step 6: Continue to work all the way around the tire until one whole side is off. Step on the middle of the rim and pull the tube out, taking care to ease the valve stem out through the hole in the rim.

Step 7: Flip rim and tire up to vertical, and insert tire iron as shown to pull second side toward the same as the first. Use the other iron to pull the bead off. Once you get about 1/4th of the way around, you should be able to simply jerk the rim out of the tire.

Congratulations. You are now halfway through the project.

neduro screwed with this post 03-21-2007 at 03:28 PM
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