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Home Brewed Tire Mounting and Balancing

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  • Home Brewed Tire Mounting and Balancing

    Home Brewed Tire Mounting and Balancing
    by Mike Saar

    What is involved in mounting and balancing a motorcycle tire?

    Mounting and balancing a motorcycle tire is the same as a car or bicycle tire. Take off the old tire, put on the new tire, balance the assembly so it doesn't cause vibration at speed. Of course most people don't balance bicycle tires...

    Can I do it myself?

    Sure you can! It just depends on how much time you have, how hard you want to work at it and if you want to buy more tools. Personally, my Dad and I had a rule about this last part. New job, new tool! (Yea!)

    Why should I pay a shop to do this for me?

    If you are not into hands-on motorcycle maintenance, sweating, hard labor, possible damage to
    hands and body and swearing (a *very* important part of mounting tires), then pay someone to mount and balance your new tire.

    Why should I do it myself?

    You'll take pride in your work. It will be done right. You will show extra care when working so as not to scar those lovingly polished alloy wheels. You can change out bearings, check brake
    pads for wear and all the little things that need to be checked on the front end of your machine. After the initial outlay of money for tools, mounting and balancing will be free for the rest of your riding career. You get to buy more tools (did I mention that already?).

    Where should I buy the tire and why?

    You should buy the tire where (a) you get there best price and (b) you get the best service. Go to your regular dealer and check their prices both for the tire and for the mounting/balancing. Some places offer list price or a very small discount but include the mounting and balancing. Others deep discount the price and then charge you $25-50 (USD) to mount and balance. The mount and balance charge most often doubles (sometimes triples) if you walk in off the street with your wheel and tire.

    In defense of this practice, the dealer is in business to make enough money to keep his family sheltered, clothed and fed just like everyone else. To accomplish this, he's got to make a profit.

    For instance, let's say you buy your tire from the Discount Sammy's Midnight Bike Parts, Inc.
    Winter '01 Catalog (now don't go lookin' for the url or the catalog ... I made it up!) for say $95. Then take it to your dealers shop for mounting and balancing. Your dealer has not only lost any marginal profit he may have received from a tire sale but now he has to pay a mechanic for the one hour or so that it takes him to mount and balance your Discount Sammy's purchase. And you expect him NOT to try and recover his loss?

    Another aspect of this question is how old the tire you purchase may be. There are companies out there that sell tires that are old or seconds or blems or even some combination of the three. They don't say this in the catalog, in the sales add, on the website or on the telephone unless you ask about it. If you go to a reputable dealer he'll sell you first rate tires. He wants your return business. If he doesn't, he won't be in business for long. There really are companies that actually value their customers and sell only first rate stock. Really!

    How difficult is it to mount and balance a tire at home?

    Nothing worth doing is ever easy. And anything worth doing is worth doing well. Mounting and
    balancing your own tires is labor intensive. But with the correct tools can be done by any but the dangerously inept. Of the two type of tires involved, each has it's problems. Tube-type tires has the problem of pinched inner tubes. With tubeless tires the problem is that in order for the tire to seal tightly against the rim it must have a special bead seated just so and of necessity that bead is very strong and considerably smaller than the outside diameter of the rim.

    How much time will it take?
    It should take somewhere around 2 hours, most of which is the balancing part.

    What special tools and equipment do I need and how much is it going to cost?


    1. Tire irons - Available in different lengths, 8"-16", usually the longer the better. A longer lever allows you more leverage making the job easier. There are also tire "spoons" from
      Motion Pro and a "Breezer" tire tool, but not having used either I won't comment. Price
      ranges from $5-25.00 (USD) apiece. You'll need a minimum of two, better have three
      and maybe a fourth just in case. (There are times....)


    2. A set of door edge guards, the kind you just slip over the edge of your car door to prevent it from bumping another object. Use these to slip over the edge of the rim while using tire irons to protect your wheels.


    3. Compressed air source (a nearby service station will do but compressors are really nice to
      have). Cheaper than that is a portable air tank that you can put in the back of your car and
      fill up at the local service station.


    4. A bead breaker is nice but not really necessary. You can go to a good hardware store and
      buy a glueing clamp and it will work very well, thank you. These are two blocks of hardwood, vaguely wedge shaped, with two hand screws used to tighten them down. Perfect for the job of break motorcycle tire beads away from the rim.


    5. A twenty gallon drum with heater hose slit lengthwise used for padding around the rim. A
      nice addition to this would be a long piece of sturdy all-thread set into about 8" of concrete at the bottom of the drum. Add a matching wingnut and large washer and you have something that will hold the wheel really well while you are working. Or a really nice wheel holder/tire changer like Terry Cable's Moose Tire Changer for about $90.00 (USD) or M plus M's Quick Change Tire Machine $249.95 (USD) plus hitch mount or floor mount at $39.95 or $64.95 (USD).


    6. Wheel weights - most folks use the stick-on type weights.


    7. Tire mounting fluid - don't use dish detergent! This can lead to your wheel sliding around
      inside your tire under extreme acceleration(rear) or braking(front).


    8. New tires - oh, yeah! That's why we're collecting all this stuff, isn't it?


    9. Scotchbrite pads - to clean off the gunk that stays between the tire and the rim when the
      guy at the dealer doesn't care enough to do the best job for you. You can also use laquer
      thinner (in a well ventilated area, please) to take it off. Either way you'll have to apply
      some elbow grease.


    10. Tire valve core tool - to remove and replace the valve core. Makes life much easier when you are not fighting air pressure along with rubber and a wire bead....


    11. Mag wheel polish (come on... while you've got them off, give them a real good polishing)


    12. Any of several possible balancing tools from a couple large milk crates and your axle to a
      Snap-On Dynamic Wheel Balancer (big bucks). Most folks will opt for the Spec II
      Telefix Balancer for about $150 (USD). There is also a bubble balancer available that
      works along the lines of a lawn mower blade balancer. A large metal cone, over which
      you place your wheel and tire assembly, that rides on a pointed metal rod. You balance
      your wheel buy adding weights to various locations around the rim as close to the
      centerline as possible.


    13. A small tube of silicone sealer/caulk. This you use to seal the edge of the tape weights.
      This helps keep dirt, water and oil from getting between the weight tape and the wheel
      helping to keep the weight in place.


    Okay, I am going to do this myself. Now what?
    First, take the wheel off the bike. Let all the air out of the tire, best done by removing the valve stem core with the proper tool.

    Using either your bead breaker or a glueing clamp, break the bead of the tire away from the rim.
    Now position the wheel on a holding device such as a twenty gallon drum or tire changing stand.
    Now pull the tire as far to one side, diametrically, as possible by pushing the two tire
    beads on the opposite side together and making them go down into the narrowest part
    of the rim. (Please see the cross section diagram to the right)

    Slip one of the tire irons between the near bead (the bead which is facing up as you work) and the rim on the "loose" side of the tire and pry the bead over the near edge of the rim. Slip another iron under the bead three or four inches from the first and roll the bead over the near edge of the rim. Pull the first iron out and leap frog it to the other side of the second or if you have a third iron place it three to four inches from the second iron and roll more of the bead over the rim. Do this leap frogging tire irons until you can just roll the rest of the bead over the edge of the rim.

    You should now have one bead off the rim and one on. Repeat the work with the tire irons only
    this time, since the object here is removing the tire from the rim, you'll be working the far bead over the near rim. You can also work the flip the wheel over and work the tire off the rim so that it comes off on the far side of the wheel but I think it's easier to pull it toward you. At this time take out the old valve stem if you have tubeless tires. You should replace these and tubes (for tube-type tires) as often as you replace tires.

    Next you will want to clean up the bead area of the rim. Be sure to clean all the built up rubber and dirt from this area. This will assure a good seal between tire and rim. You can use a
    scotchbrite pad being careful not to take off metal in your efforts. A friend of mine uses a rag and lacquer thinner because there's no chance of taking off metal that way. If you choose this method please use it in a well ventilated area. Clean the valve stem hole, too.

    Put in the new valve stem. You will have to seat it using the valve stem tool to pull it into
    position.

    You can also use this time as a chance to check your wheel bearings and rotors. You can also
    shine those alloy wheels up real good.

    Next you can balance the wheel alone, if you desire. Sometimes this is a good step. This will give you a jump start on balancing the wheel/tire assembly. My friend, who works in a performance bike shop, swears that this step lessens the amount of weight he uses balancing a
    wheel/tire assembly.

    Your next step is to get the tire on the rim.

    Lubricate both beads of the tire with wheel mounting fluid. This is very important. This fluid lubricates the bead of the tire making it easier to mount but when it dries it get very tacky. It is extremely important that you use a lubricant designed for mounting tires. If you use dish soap mixed with water you run the chance of your wheel rotating inside your tire under hard acceleration or braking. This will negate all your balancing work and you wont be able to tell why your wheels are all of a sudden out of balance.

    Now look at the tire and find the rotation arrows. Be sure to have the tire rotating the correct direction when it is on the bike.

    Slip as much of the bottom bead over the wheel as you can without using the irons. Now, bit by bit, pry the rest of the bead over the edge of the rim. This is where tube-type and tubeless tires part company. If you are working with tubeless tires continue reading. If you are working with tube-type tires skip to the paragraph labeled Tube-type tire mounting.

    Next, do the same operation with the top or near side bead.

    Now to seat the bead. This either requires a lot of air or some ingenuity. First find the yellow dot on the sidewall of the new tire. This dot signifies the light spot on the tire. Place this dot at the valve stem. You may have to relocate this dot several times to get the ideal spot for it. The object of this exercise is to use as little weight as possible when balancing the assembly.

    If you do not have a strong compressed air source then take a length of rope or a web clamp
    (usually used to glue chair rungs in assembling chairs) and wrap it around the circumference of
    the tire. Tighten the rope, using the tourniquet technique, or the web clamp down so that it
    presses the crown of the tire down in between the beads forcing the beads into contact (and
    hopefully creating a good seal) with the rim. Hook up your air source and start to pump up the
    tire. As the air fills the tire slowly release the pressure on the clamp or rope allowing the tire to go back to it's normal shape.

    Continue pumping in air until the bead fully seats. There is a fine line molded into the tire about 1/8 inch above the bead all the way around the tire. This line should be parallel with the rim all the way around on both sides of the tire. You should try for less than 1/64 inch variance in measurement between the rim and this line. If it varies more, then the bead has not seated correctly. Continue pumping in air up to about 50 or 60 psi. If it still doesn't seat let out all the air, break the bead loose, spread a little mounting lube along the bead and try again. It should work.

    Tube-type tire mounting...

    Okay, you have one bead over the rim. Find the yellow dot on the tire. This signifies the light spot of the tire. Place tire so that this dot is located at the valve stem hole. Now get out your inner tube and starting at the valve stem, position it inside the tire. Be sure you get the stem fully seated in the hole and don't allow the inner tube to twist. This is best accomplished by putting just enough air in it to keep it inflated but just barely. This little trick will also help to keep the tube from being pinched by tire irons and beads. If you pinch the tube it's going to leak so be careful.

    Now repeat the process of getting the bead over the rim on the near side bead. Be careful not to pinch the inner tube. Fill the tire with air and you are ready to balance.

    The Balancing Act

    The objective here is to get rid of the vibration caused by an out of balance wheel/tire assembly. The closer you get to perfectly balanced the better. At the same time you need not get carried away. Within 1/4 ounce is usually good enough. Remember that as you ride the tire will wear and probably become unbalanced on it's own over several thousand miles. If you really want to check your work after you've balance the assembly, stick a 1/4 ounce weight anywhere on the rim and spin it or check it again. Do this at a few locations. As long as the added weight always is at the low point you can be sure that your assembly will be balanced to within 1/4 ounce.

    In addition to getting the truest balance possible you should try to use as little weight as possible to bring the assembly into balance. Racers will not accept more than 3/4 oz. (~20 grams) up front and 1 ½ oz.(~40 grams) on the rear. If you find you are using more than a couple ounces try rotating the tire on the rim a bit to get a better initial balance.

    On the subject of the liquid balancer/sealers, popular opinion is that while it works well it also creates a mess and sometimes hazardous conditions when taking the old tire off the rim. Tire manufacturers say that the liquid balancer/sealer adds excess weight and retards heat dissipation when used in a tire. They also warn that liquid balancers have never been proved to balance wheels for running at triple digit speeds. Many shops these days are charging extra for mounting if you have used either balancer/sealer or the "Fix-a-Flat" type emergency tire repair in an aerosol can. Personally, I've used liquid balancer/sealers until recently and never had a problem but I was using it in tube-type tires. I have never used it in tubeless tires. I can imagine it would be an extra mess to clean up before mounting a new tire and as such I can't blame the shops for charging extra.

    There are several ways to balance tires. You can use a couple tall milk crates and your axle
    suspended between them as long as your wheel bearings are in excellent condition. You can go
    out and purchase a dynamic balance machine from Snap-on (big bucks!). Or come up with
    something in between such as the afore mentioned Tele-fix balancer for $150 (USD). There used
    to be a balancer around that was cheap and reliable using an oversized lawn mower blade
    balancer and a bubble level, but I haven't seen one in quite awhile. The nice part of the Telefix balancer is that the wheel rides on oiled bearings which turn much freer than greased bearings used as wheel bearings. This makes it a bit more precise (but just a little) and quicker in finding the heavy spot versus using the axle suspended from a couple milk crates. Wheel bearing grease slows the wheel down a bit when it is spinning at slow speeds and your marks will therefor vary a bit. The method still works well though.

    To use the most readily available method (Milk crates and good wheel bearings or a homemade
    equivalent) you simply take your wheel and tire assembly (with the axle) and prop it up in the
    crates so that the wheel rotates freely. If you notice that your wheel has a jerky motion to it or it seems to come to an abrupt stop check and/or replace your wheel bearings. Also while you are watching your wheels spin you can check the wheels, rotors and tires for any out of round (up and down) or warp (side to side) conditions. Should you find either, fix that problem before
    going any further. The reason is that and change made, such as replacing or refacing a warped
    rotor, could change the balance of the wheel assembly negating all your hard work.

    Give the wheel a good spin so that it spins for a little while before stopping. You want the first couple spins to be fast so you loosen up the grease in the bearings. Mark the high spot with chalk. Spin again and mark. Do this at least three times. Now you should have three or more marks most likely in the same area of the tire. The mean of all the marks is the light spot. Tape a wheel weight in place temporarily, with scotch or duct tape. How much weight to use depends on how far apart the marks are. If they are far apart use less weight. If they are closer use more. Spin the wheel again, mark the high spot. Is it the same as the first set of marks? Tape on a larger weight in place of the smaller. Does the wheel stop at a place 180 degrees around from the first set of marks? Remove the first weight and replace with a smaller weight. Continue this until your marks are random when you spin the wheel six or seven times.

    Your next step is to semi-permanently attach the weights to the wheels. Using the tape weights makes this pretty easy. Remove the backing from the glue surface of the tape weight and press onto the wheel in the exact location where it was taped. Of course this area must be cleansed of all grease, oil and dirt for the tape to stick well. Next apply a bead of sealer around the edge of the tape weight and, with a moistened fingertip, smooth the sealer around and over the weight. This will help keep dirt and oils from between the adhesive tape and lead weight or the wheel surface.

    As far as using a computer/machine balancer goes, the machine does the same thing only quicker. AND if the machine is off, it's way off. From my observations the machine does a good job in competent hands and if you take the assembly completely off the machine and then put it back on to check your work. For those of us with more time than money.... I'd stick with the milk crates. I figure since most of the race teams use the Telefix type balancer *not* the high dollar computer machines, something like that is definitely good enough for me.

    Bibliography:

    personal experience, Rob Pryor (Technician/mechanic - Cycle Performance Engineering,
    Clinton, Maryland), JP Honeywell (XS1100 Owners Association/Long Distance Riders List),
    Mike Cummings (XS), Mike Sachs (LDR), Greg Roberts (LDR), Motorcyclist Magazine, Chris
    Norloff (LDR), William Boyd (LDR), Jan Cutler (LDR and Owner - Reno BMW), Greg Roberts (LDR),
    David R. Neal (Concours Owners Group)

    Contacts:

    Spec II
    8927 Lankershim Blvd
    #cw
    Sun Valley, CA 91352
    818-504-6364

    M Plus M
    81 Highland Road
    Mansfield Center, CT 06250
    860-456-8037

    Terrycable
    17376 Eucalyptus Street
    Hesperia, CA 92345
    800-854-4691
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