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Tubeless Tire Repairs Tubeless tires can be plugged to get you to the nearest bike shop, but in general you should plan on replacing the damaged tire as soon as possible. The usual method of temporarily repairing a tubeless motorcycle tire is to insert a rubber plug through the hole, using a special tool. Some plug kits contain a sticky string material that is jammed into the hole with a tool. The string stuff is typically what you’ll find at gas stations and auto parts stores. The weapon of choice for many long distance riders is the "Stop & Go Pocket Tire Plugger" kit, which has a reamer for opening up the hole, and a hollow tool for inserting a mushroom shaped plug into the tire. The head of the plug expands inside the tire, preventing it from working out. BMW tubeless repair kits include a donut-shaped plug that’s lubricated with rubber cement and pushed through the hole with a steel hook. The shank of the insertion tool has rough teeth to help ream out the hole. The kit includes CO2 cartridges and a short plastic connector to reach the valve stem. But the truth is, if the tire is steel belted, it’s a real bugger to get the plug inserted through the mesh of tough steel wires. Nor can you depend on a soft rubber plug lasting very long. The belt wires can nip off the plug within a few miles. Just be aware of the limitations of plugs—don’t be surprised if you have to plug the same hole several times to get you back to civilization. Automobile tires are commonly repaired with an internal patch that is bonded to the inside of the tire over the puncture. That’s reasonably safe for an automobile, but motorcycle shops are justifiably nervous about patching a motorcycle tire the same way. Stop & Go does make a "permanent" plug that installs from inside the tire like the auto patches, but that requires breaking the bead to get inside. Frankly, if you can limp in to a motorcycle shop on a plugged tire without any further disaster, best advice is to bite the bullet and replace the tire with a new one. Wait! Don’t pull that nail! One little suggestion: if you see a big nail imbedded in the tread of your tubeless tire, You’ll want to get out your pliers and yank it out immediately. But leave the nail in place until you’re ready to plug the tire. That little hole can be awfully hard to find after you pull out the offending nail, and the nail will help slow the leak. Do the exact opposite with a tube-type tire. Pull the nail immediately, but mark the spot on the tire. A nail left in a deflated tire can make a whole row of new punctures in the innertube just by rolling the bike forward a few feet. It should go without saying, but we’ll say it anyway: if the puncture is in the sidewall of the tire, there is no way to repair it safely, whether tube-type or tubeless. You’ll need to get a new tire. Pumpety-pump Once the hole is plugged, the tire needs to be reinflated. One
approach is to use CO2 cartridges, which are connected to the valve
stem via a short plastic tube. However, the reality is that it takes
several cartridges to inflate a tire, and once you’ve expended them,
that’s it. Older BMW "airheads" came with a hand pump secured under
the saddle, but it’s really awkward trying to hold the pump in
position while working the handle, and those of us who have done it
can verify that it takes a whole lot of strong-arm pumping to
inflate a tire to even 30 psi. The most practical approach is to carry an electrically powered pump such as the Cycle Pump, Sparrow, or Air Man. The downside of these tiny electric pumps is the very slow air flow. It may require 5 to 10 minutes of pumping to inflate a large rear tire, but when you need air, you’ve got it handy. And if the plug spits out, you can replug the tire and pump it back up to keep going. More than a few riders use their electric pumps to keep their tires up to desired pressure, rather than stopping at a gas station.
Photos: The combination of the Cycle Pump and EZ Air gauge allow a rider to get air into the tire easily with an accurate reading anywhere along the ride. There's no need to find the next gas station. At $100 for the pump it's not cheap, but the durability of the metal box outdoes it's nearest competitor.
One real limitation of the small electric air pumps is that they generally can’t pressurize the tire fast enough to push the bead against the rim. So, if you need to get a tubeless tire reseated on the rim, you’ll need an air source with a much greater flow rate. One simpler-but-sneakier approach to popping a bead is the Best
Rest "Donor Hose". It’s just a length of air hose with chucks on
both ends, about long enough to reach from your motorcycle tire to
another tire. A Donor Hose will pop a reluctant tubeless tire onto
the rim and fill a motorcycle tire within a matter of seconds. We
can understand how tempting it might be to sneak over to some truck
tire while the driver is For those occasions when you need to let air out of a tube or tire, it’s necessary to have a tool to remove the valve core from the stem. You could carry a valve tool that has both a core remover and a tap to clean up damaged stem threads. But the most practical technique is to install metal valve caps with core remover ends—available at auto parts stores. Avoiding Tire Failures The good news is that today’s tires are very durable, and actual blowouts of the carcass are very rare, unless you’ve done something naughty to your tires. Let’s note that a tire carcass is a flexible composite of organic rubber compounds, fabric cords, steel bead wires, and often extra steel belts in the tread area. The tire is made rigid enough to handle side loads (such as steering input), but flexible enough to absorb small pavement irregularities. To do it’s job, a tire needs to be inflated to the correct air pressure. If the pressure is too high, the tire will be too stiff, the ride will be harsh, the contact patch will be reduced in size, traction will be reduced, and wear at the center of the tread will be accelerated. If the pressure is too low, the tire will flex excessively, steering will be "mushy", the shoulders of the tread will wear prematurely, and the rim can be damaged by impacts. Note that a flexing tire carcass generates heat. A tire that’s under-inflated by just 10 psi can cause permanent internal tire damage, especially if the bike is overloaded, or speeds are aggressive. Once the damage has been done, the tire is an accident waiting to happen. It may not fail today or this week, but we shouldn’t be surprised if it suddenly comes apart a few thousand miles down the road. Since the primary way to avoid blowouts is to maintain tire pressures, we need to check our tires before every ride. Motorcycle tires are so rigid that you can’t easily spot a low tire just by looking. If a tire looks low, it’s probably under 20 psi. You really need to check pressures with a gage. "Pencil" type gages are cheap and reasonably accurate. The place to start is to look up the pressures the manufacturer lists for the bike in your owners manual, or on a placard on the bike. Note that tire pressures are normally increased for heavier riders, two-up riding, extra loads, or higher speeds. Recommended pressures are sometimes listed in bar, sometimes in kPa, and sometimes in psi. We’ll include a handy pressure conversion chart at the end. But let’s note that the pressures recommended by the bike engineers are for the stock tires that came with the bike. If you change to different tires, then it’s time to consult the tire manufacturer. Believe it or not, there are tire specialists eager to discuss your bike with you, and recommend tire pressures for different conditions. So, get their phone numbers, and ring ‘em up for a discussion. Tires spoil, just like apples Let’s also note that tires are "organic". That is, more like apples—less like steel bars. Tires "spoil" within a few years, especially when exposed to sunlight. The outside of the rubber gradually hardens and cracks, while the internal rubber loses elasticity and strength. Fortunately, tires are dated. So, a clever rider checks the manufacturing date on a tire before buying. Frankly, you shouldn’t even think about putting on "new" tires that are older than five years. The date is coded, of course, to make it less obvious that a tire is getting "stale". The date code is the last digits of the "DOT" number, which represent week and year. So, a serial number such as "DOT ATCX 4 1004" would be the 10th week of 2004—the second week of March, 2004. Prior to 2000, the date code was in 3 digits. If any of your bikes have tires with only 3 digits for the date codes, I’d strongly suggest replacing them immediately.
For those of us who have several machines, or don’t put down many miles per year, it’s important to get the freshest tires available, since those tires may be on the bike for several years, gradually dying of old age rather than being worn out. If you see ozone cracks in the rubber, the tire is history. Photo: The manufactured date is the last 4 digits on the DOT line, for tires manufactured after 2000. One other caution with tube-type tires. Install a new innertube with a new tire. Blowouts of tubes can almost always be traced to an aging tube that was re-used in a new tire. As I’ve discovered for myself, an old innertube may look perfect, but the rubber can be rotten and ready to split a few miles down the road. Trust me on this one: "New tire; new tube."
Good News, Bad News The good news is that today’s tires are so tough that sudden deflations are a rare occurrence that few riders will have to experience. The bad news is that there are lots of sharp thingies lying on the roadways, and there are also a few nasty people around who think it’s fun to spike or slash motorcycle tires while you’re not looking. So, this would be a good time to check your tire repair kit and ensure you’ve got what you need on board to fix a flat. Most importantly, get in the habit of checking your tires before heading out on a ride, so they don’t self-destruct. David Hough is a long-time motorcyclist and journalist. His work has appeared in numerous motorcycle publications, but he is best known for the monthly skills series “Proficient Motorcycling” in Motorcycle Consumer News, which has been honored by special awards from the Motorcycle Safety Foundation. Selected columns were edited into a books “Proficient Motorcycling and More Proficient Motorcycling” published by Bowtie Press. He is also the author of “Driving A Sidecar Outfit.” A pocket handbook, “Street Strategies” is also on the market now.
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