Wecome To RVs and OHVs

This blog is all about RVs (recreational vehicles) and OHVs (Off Highway Vehicles), camping, sailing, and survival
and how they work together to provide wholesome family fun and great learning opportunities.
Many posts are intended to familiarize novice campers and RVers with RV systems and basic camping and survival
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Sunday, July 21, 2013

Changing A Dirt Bike or ATV Tire

Flat tires are an all too common problem when riding OHVs.  The sometimes rough terrain tends to take its toll on tires and tubes.   I've seen riders land hard enough doing jumps to pop a tube or just blow the air out of their tires and there are plenty of nails, sticks, thorns, and sharp rocks out on the trails or around camp to poke holes in things.  We once used a magnet to pick up more than 10 # of nails around one camp site where previous users had apparently burned stacks and stacks of pallets.

Changing a tire out on the trail is not something you usually want to tackle, but it can be done if you have the right tools and repair materials with you.   Dirt bike tires are usually stiff enough that you can limp back to camp on a flat and change it there.  ATVs are much harder to drive with flat tires.   When I worked as an ATV mechanic at a resort we would install a spare on site or trailer rentals with flat tires back to the shop to fix flats.  Sometimes you can temporarily fix a tire using "Slime", that sticky green stuff, or some other "Instant flat repair" if you have some in your pack.  If you choose to carry flat repair, make sure it is the pressurized cans to refill the tire as well as seal the leak.  On the trail you may be able to stand your machine on a rock or log to support it while you remove and work on the tire.  Make sure it is stable or have someone hold onto it so it doesn't fall off and get damaged or hurt you.

The procedures for changing a tire in camp or on the trail are pretty much the same.   However you may have better facilities in camp to make the task easier.  First, raise the flat tire off the ground using a jack, jack stand, or blocks.  Make sure the machine is well balanced and stable so it doesn't fall on you while you're working on it.  Loosen the axle nut and pull the axle out, then remove the wheel and tire.  Lay the tire down on the sprocket side.  This reduces the potential for bloody knuckles as you remove the tire.  If you have disc brakes you'll have to slide the rotor out from between the pads to remove the wheel from the machine.  You might have to slightly compress the calipers to release pressure between the pads and the rotor.  If there is any air left in the tire, remove the valve stem and let all the air out.  Remove the nut from the rim lock and push on the rim lock bolt to push the rim lock into the tire and away from the bead.  This is most easily done by standing the tire up with the rim lock on the bottom and putting the flat side of a tire iron through the spokes and over the rim lock bolt and pushing down with both hands.   Then lay the tire back down and prepare to break the bead loose from the rim.   This can be difficult if you don't have special tools.  Sometimes you can just step on the tire but most often it will require significantly more force.  Tire shops use pneumatic presses to separate the bead from the wheel.  You can buy a manual bead breaker that just uses leverage.  In camp I use a small sledge hammer to loosen the bead.  Be VERY careful not to hit the rim!  When the bead is free from the rim, insert a tire iron between the bead and the rim and lever the bead out over the rim.   Hold the first tire iron and insert a second one a few inches from the first and again lever the bead over the rim.  You CAN make it work alternating two tire irons, but I find it easier if I have three so I can hold the tire in place while I get another bite with the third iron.  Keep working your way around until the whole bead is on the outside of the rim.  Having a helper to hold at least one of the tires irons makes it a little easier.  From here you can remove the tube and repair or replace it without having to completely remove the tire.   Of course, it the tire itself needs to be replaces you'll have to remove the tire.  Align the wheel so thelower edge is outside both beads, then use essentially the same procedure with the tire irons to work the tire off the wheel.   I found a tool that makes getting both beads off easier.  It is a cylinder with a notch in one end that slips over the rim between the tire and the rim.  You then hold the other end with one hand and use a hammer to drive the engaged end around the rim to lift the bead off the rim.  Another handy tool is a "Bead Buddy".  These clamp to the rim and serve as kind of a "third hand" to hold the tire in place while moving the tire irons.  There are even small, plastic clips you enough you can carry in your fanny pack or fender bag for this purpose.  They don't have to be big enough to apply much leverage -- they just need to keep the bead from slipping back over the trim while you move the tire iron.

Inner tubes are a lot more expensive than tire patches and many times a patch is all you need to get back on the road.   If the valve stem is damaged or torn loose from the body of the tube you'll have to replace the tube, but simple punctures can usually be successfully patched. I prefer to use "hot vulcanizing" patches instead of the flimsy little, self adhesive,m bicycle tire type patches.  I believe they make a stronger and more permanent repair, but I've also used the "peel and stick" patches on the trail in an emergency.  Hot vulcanizing patches are attached to a little diamond shaped metal pan that contains a combustible material.  You peel the protective film off the patch, put the patch over the hole in the tube, then clamp the metal dish to the tube using a special clamp. Then you light the material in the dish and let it burn until it goes out.  Wait a few minutes for the metal to cool, then remove the clamp and carefully pull the metal dish away from the patch.  Your patch should be securely sealed in place.

Installing a new or repaired tube requires some care to ensure you don't pinch the tube with the tire or damage it with the tire irons.  A little talcum powder or baby powder on the tube will help keep it from sticking inside the tire and allow you to more easily move it into place and align the valve stem with the hole in the rim.  Put a little (but not too much!) air in the tube so it has shape before you begin to install it.  Line up the valve stem with the hole in the rim, push it through and install the valve cap, then gently stuff the tube into the tire all the way around the rim.  Next you'll need to get the outside bead back over the rim using tire irons.  This is basically the reverse of removing the bead.  Take care not to pinch the tube with the tire iron or you'll be doing the whole job over real soon!  Make sure the tube is inside the rim lock and push the bolt for the rim lock through the matching hole in the rim.   Start the nut on just enough to keep the bolt from falling back through the hole until you're ready to tighten the nut.  Once everything is in place, inflate the tire until the bead snaps back onto the rim.  Check to make sure the bead is evenly spaced all the way around the rim.   If there are shallow spots you may need to add air and over-inflate the tire until the bead pops into place.  You will usually hear a sharp "pop" when this happens.  When you are satisfied that the bead is properly seated, tighten the nut on the rim lock, then adjust the tire pressure to where it should be for riding.   That usually means letting out some of the air it took to seat the bead.  Then reinstall the tire and wheel assembly, making sure the brake disc (if so equipped) is properly aligned and the chain is correctly installed on the sprocket.  Adjust the axle aligning bolts equally until the chain is straight and has the proper tension, then tighten the axle bolt and nut and hit the trails again!

Pumping up your tire on the trail . There are two basic options: a hand pump or a CO2 powered inflation kit.  Hand pumps are inexpensive but because of the limited size for carrying on the trail it is going to take a lot of pumping to inflate a tire.  CO2 powered inflation kits make it easy, but those little cylinders, about the size of your thumb, aren't going to fill a lot of tires.  Big, puffy ATV tires take a lot more air than narrow dirt bike tires.  Back in camp you can use a regular manual tire pump or, if you have it available, compressed air.  Even a little 12-volt compressor that plugs into a cigarette lighter can save you a lot of pumping.

A tire changing stand is not necessary but will make the job a lot easier and keep you from kneeling in the dirt and gravel.  It keeps the wheel (and you) up out of the dirt and some models include a bar that can be used to remove the bead.   Another handy tool is a bead breaker.  This consists of a curved bar that fits along the bead next to the rim. The bar is attached to a lever which in turn is attached to a stand that also has a "foot" that goes under the tire.   Pushing down on the lever once everything is aligned forces the lip of the bar between the tire and the rim and pushes the tire down off the rim, making it easier to get your tire irons in place to work the tire off the rim.   Of course you won't have these with you out on the trail, but they make the job in camp a lot easier.

Bicycle tires are handled about the same as dirt bike tires, but because of the smaller size, lighter weight, and softer rubber you will find the task easier.  Tire irons for bicycle tires are much smaller than regular tire irons and usually have a notch that fits onto the spokes to hold one in place while you move the other.  Bicycle tires can usually be successfully patched using simple peel-and-stick patches.

Happy patching!

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