Motorcycle Tire Mounting and Balancing Tips

Trading Tread in Your Garage

1. In order to appreciate advanced tire technology, you must first mount a set onto your motorcycle. Most places selling tires also mount them, but if you like doing your own work when possible, mounting your own tires may be a project to consider. The main drawback might be the expense of the tools necessary to perform this simple, but monumentally important, task. For motorcycle tire mounting and balancing, allow yourself at least a couple of hours to finish the job. But if you're like most first timers, it can easily stretch into a whole afternoon.

2. All tires are softer, and therefore easier to manipulate, when warm. Direct sunlight for 15 to 20 minutes per side will usually do the trick. The old tires can be warmed up the same way, too. In cold conditions, take the tires and wheels into the house and let them warm up to room temperature. Remove a wheel from your motorcycle and deflate the tire by removing the stem cap and tire valve. Use the tire bead breaker to "break the bead" (separate the bead from the rim). Work the bead breaker into position as close as possible to the edge of the rim and use an open-end or crescent wrench to "squeeze" the edges of the tire (the beads) to the center of the rim. Work the bead breaker around the rim if you must to ensure total bead/tire separation.

3. Once the bead is broken, use soapy water to lubricate the area of the tire that is to be worked over the edge of the rim first. Insert two tire irons under the bead approximately six to eight inches apart. Work the rest of the tire's bead area into the center drop of the wheel on both sides. Pry the spoons up and over the rim one at a time. This process requires some manhandling. Be prepared to use your thighs to help hold the wheel down. (There is a good chance that you and your clothes will get dirty.) When both spoons are pried over, either introduce the third tire iron or work one of the two free for the next step. Use one hand to hold down the two initial spoons while you pry up the next section (two to four inches) of the tire bead with the third spoon. After prying the third spoon up and over the rim, the center spoon will become free and you will be able to retrieve it easily. This modus operandi will allow you to repeat the process as long as necessary to remove one side of the tire.

4. Lubricate the inside of the remaining bead and flip the wheel over. Work one side of the bead into the center drop and use the palm of your hand to work the opposite side down and off the edge of the rim. If this proves more difficult than it sounds, use the flat side of the tire iron to get a prying start.

5. Check the wheels for damage and cracks, and clean the wheels thoroughly. Remove any old balance weights and adhesive tape. If they pass inspection, clean the rim beads with a wire brush before you install the new tire. Dust, minerals, sand, rubber and other particles become trapped and compressed between the tire and the rim. Deposits of this nature account for slow leaks, problematic tire-bead seating and require more weight to balance the wheel. Inspect the tire stem for similar deposits. Rubber tire valves are subject to aging and cracking. As inexpensive as rubber tire valves are, you might consider replacing them for good measure. On metal stems, inspect the condition of the O-ring and retaining nut. If the retaining nut is on the inside, be sure to lock the nut in place, use thread-lock, center-punching or double-nutting.

6. Before mounting the new tire, look up a few details that must be observed for proper fitment. The most important is the directional arrow designating the direction in which the mounted tire should rotate. This is a critical step. If the tire is mounted counter-rotation, it is very likely that the tread "slice" will separate, leading to eventual and possibly rapid deflation. The next point of interest should be the balance marks. The yellow paint circle on Dunlops denotes the light spot and should be mounted at the tire valve. Metzeler uses two red dots for the same designation. Check with your tire source for any details pertaining to your particular tires. Also, get the manufacturer's recommendation on tire pressures for your application.

7. Lubricate the tire with soapy spray and position it on top of the wheel as you intend to install it. Grab the tire at east and west points on the compass and work it over the edge of the rim by hand as far as possible. Then rotate the wheel or yourself 180 degrees and use your right heel to put pressure at the point where the tire is being worked over the edge of the rim. On the opposite side, place a tire iron about three to four inches in front of the bead mounting point and work the tire bead over the edge of the rim, one stop at a time. If you have help, use a tire iron instead of your heel and have someone hold it in place while you use the other tire iron to work the tire bead over the rest of the rim. Be sure that the beaded section of the tire stays in the center of the rim. If you observe this last detail diligently throughout the tire mounting process, the job will always be easier. For the second bead, use the same method, only now both beads will have to be positioned in the center of the rim. If it seems that the bead at the mounting point requires a lot of stretch to be worked over the rim edge, there is a good probability that one or both of the tire beads are not properly placed in the rim's center drop.

8. Slip on some eye protection, apply soapy solution to the tire bead area and inflate the tire until the beads snap into place. If your air chuck will function with no tire valve in the stem, inflating and beading will be easier. There should be two loud pops when the beads slip into place, one for each side. As soon as you hear the second pop, release the air and allow the tire to deflate completely before reinstalling the tire valve and airing it for real. Deflating the tire after it was just beaded and then reinflating it allows it to stretch on the wheel evenly, and results in a rounder tire. Remove all tire stickers and tags, if possible, and get the wheel ready for balancing.

9. Find a flat, level section on your floor or work bench for your balancing stand. If you use a work bench, secure the balancing stand to the bench with a "C" clamp. Run an axle through the wheel and set it on the stand. The obvious phenomenon at work here is that the heavy side always rotates to the bottom. Slow the tire motion down to reduce the pendulum effect. When the wheel stops, mark the top/center of the tire as your light spot. The speed with which the heavy spot rotates to the bottom should indicate how far out of balance the wheel is. With practice you should be able to translate that into an appropriate guess of the amount of tire weight needed. For starters, you can take a wild guess and attach some lead weight using only duct tape, to the light (top) spot. If the tire still rotates the heavy side down, then it needs more weight. If the weighted light spot rotates to the bottom, reduce the weight.

10. When you have reached a state in which the wheel has become balanced, it will no longer rotate with a pendulum effect. Double-check this condition by rotating and then stopping the wheel at 90-degree increments. If the wheel remains stopped each time, it can be considered balanced. Keep in mind that securing the lead weights with duct tape will slightly increase the total weight on the wheel. This section of the wheel should have been previously cleaned with contact cleaner in anticipation of lead affixing. Back up the lead adhesive with a section of duct tape and you're set.

How and why

A 20-gallon, cylindrical steel drum, open at one end, will make tire mounting easier. The edge should be covered with a strip of heater hose (split lengthwise) to keep it from scratching your wheel. A bead breaker of any sort is a must: The better the bead breaker, the easier this aspect of the job becomes. A spray dispenser with a soapy-water solution is also very helpful, and large, spoon-shaped tire irons work the best. You can get by with two "spoons," but use three for best results. In conjunction with your tire irons, rim savers may be used to protect the edges of the rim from tire-iron gouging. Attach a zip-tie loop to each of the rim savers to facilitate easy retrieval. Other necessities include compressed air, a tire chuck, an air-pressure gauge, a wheel-balancing stand and lead weights for balancing. And while two brains may not always be better than one, four hands sure do come in handy when you are changing tires the old fashioned way.

The bead breaker (approximately $45), tire irons (approximately $10 each) and rim savers (approximately $4.50 each) were acquired from K&L; Supply Co. Call (800) 727-6767 for a dealer near you.

The combination balancing-truing stand is manufactured and was supplied to us by Rowe U.S.A. (800/531-9901). The suggested list price is $500. This stand comes equipped with a number of accessories for all facets of wheel work. Spec II also makes a balancing stand that retails for $139. Spec II can be reached at (818) 504-6364.

This article originally appeared in the December 1995 issue of Sport Rider.

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