How to Ride a Bicycle with Your Dog
Before you try to ride a bicycle with your dog, bring the bike inside and give your dog a few days to get used to it. You can place treats on the bike during this time so your dog feels more comfortable around it. Then, start walking the bike outside with your dog on a leash so it can get used to the movement. After a few walks, try jogging or sprinting with the bike so your dog gets comfortable with moving at a faster pace. Finally, start riding the bike with your dog on a leash, gradually increasing the pace and distance of your rides as your dog adjusts.
Visit a veterinarian. For safety reasons you want to first establish that your dog is fit for biking. Consult with your doctor as to whether the dog has any underlying conditions that could be exacerbated by such strenuous exercise. You also want to establish that your dog is of a breed for which this would be an appropriate exercise and that it is in sufficiently good shape. If not, start out with longer and more regular walks. Under no condition is this a safe activity for dogs under 25 lbs or under one year of age. Equip yourself. The first step in establishing your dog's safety while biking is keeping yourself safe. You will need a helmet and something to ensure that you are noticeable to potential motorists, including bright cycling clothes and a reflective device to attach to your bike. You should keep some water for yourself and your dog. Some additional equipment will be required in case of emergency. In case of emergency you should have a cellphone on you, as well as money, identification, a spare tube, and a tire pump. While it should be no surprise that you will want a bike, you also need to consider what type of bike you will need. This is an activity that it is best performed off-road, so it is important to have a bike appropriate for that. A hybrid bike will be best for riding along a path; for tough terrain you will probably want a mountain bike. Equip your dog. Some people will try to bike by holding the leash in their hand while the dog runs alongside them. This is extremely unsafe. To bike safely, you need special equipment to ensure that your dog is not strangled by a leash around their neck, pulled under the wheel, or hit by an oncoming vehicle. Thankfully all of the necessary equipment is now mass-produced and readily available for those willing to invest the time and money to keeping their dog safe. The first consideration should be safely attaching the dog to your bike. For this you will need a body harness, which, unlike a leash, will not apply pressure exclusively to your dog's neck. If possible, the harness should be padded, and not so long as to allow your dog to get far ahead of you. Also you should purchase a “baton” lead that will attach the harness to the body of the bike. This will keep the dog away from your wheel and prevent the dog from pulling on the handle in a way that would cause you to loose your balance. The next thing to consider is your dog's visibility. Consider purchasing both a reflective vest and/or a collar with a blinking light embedded in it. There are also some purchases you should consider in case the exercise might be too much for your dog. A bottle of water for your dog is highest on this list. You should, also, however, think about a dog bike trailer that will allow you to pull your dog if he or she gets too tired to run. Cooling vests can be purchased if you are concerned about your dog overheating. Foster a positive association with the bike. Start inside. Bring the bike down to the ground so that the dog can explore it. Call it over to you. Explore the bike with the dog, giving it treats, possibly placing treats on the bike. Begin walking with the bike and encourage the dog to follow you. Your demeanor is important in establishing the bike as a fun toy for the dog. Praise your dog and pet him or to create a positive association. Bring the bike along for a walk. Repeat the last exercise on a walk outside with a leash. Begin to take your dog on progressively longer walks. Make sure that the dog does not get caught up in distractions and becomes accustomed to the movement of the bike. Occasionally jog or do a short sprint so that it becomes comfortable with a faster pace alongside the bike. Teach your dog important cues. Your dog should learn cues like “slow,” “stop,” “turn” and “leave it” to be able to cooperate on a bike ride. Give your dog treats when they successfully perform these tricks. When teaching your dog these cues, it is important to use your own unique phrases. Your dog will hear “slow” or “stop” often when you are not biking and this will confuse it. Using an unusual sound or word to signify these commands will ensure that your dog recognizes them. Choose a location. You need to be careful when picking a place to bike with your dog. Trying to bike on terrain that is either too undeveloped or too congested can be dangerous. The optimal location is a lightly traveled road or a designated biking path. Riding with a dog can triple your width, making it difficult if not impossible to ride in a designated bike lane on the side of the road. Considering that your dog might be less than fully visible and its roadside etiquette rather unrefined, this is a very dangerous option. However, if there is a lightly traveled country road nearby, with a low speed limit and no overly sharp turns, this could be a viable option for biking with your dog. Mountain biking with your dog is at least as risky. Rough terrain will require precise navigation and excellent balance, which can be difficult to maintain with your dog pulling on you. Your best option will be a long straight path with no automobile traffic. You should also consider the likelihood of encountering pedestrian or bike traffic. Although this is less problematic, you still want to avoid it, especially when starting out. Start out slow and short. It will take some time for your dog to become accustomed to be the behaviors and the levels of exertion necessary for biking with you. After you have trained your dog you will want to take him or her on a short, slow ride, no more than a few minutes long. Make sure that your dog is only jogging gently next to you. Give treats and praise to build positive associations with biking. Increase the time and pace. Every time that you go out, increase the time and the pace of your excursion. Be attentive, however, to signs that you are pushing your dog too hard. If so, adjust your pace. Eventually your dog should be able to go longer distances at greater speeds. Your dog's paw pads will grow tougher with more running. They might, however, start off sensitive. Check them after a run to verify that there are no signs of damage or injury. Also be aware of limping, itching, or chewing on the paw; all of these can indicate that the paw might be injured. Inspect to make sure that there are no signs of chaffing where the harness is pulling on your dog. Throughout the ride be attentive to your dog's behavior. If she begins to show signs of laziness or appears unenthusiastic, call it a day and come back out some other time. Watch for signs of heat stroke. Heat stroke is a serious condition that can cause organ failure. To prevent heat stroke you should avoid strenuous exercise in extreme heat. Even then, you must be mindful for signs of heat stroke. Some dogs will be more inclined toward it than others. You should be particularly mindful of heat stroke if your dog is either very young or old, obese, short-nosed, has a thick coat, or has an underlying medical condition. Signs of heat stroke include: Rapid or erratic heartbeat, rapid breathing, exaggerated panting, loud heaving, excessively drooling or frothing at the mouth, vomiting, dizziness, shaking, and unconsciousness. If you suspect that your dog is experiencing heat stroke stop, move to a cooler area, give the dog a small amount of water, and sponge him or her down with cool (not cold) water. A change in temperature that is too rapid can be dangerous. Exposure to cold water Carry your dog. Whether through trial and error or because your veterinarian has told you that your dog is not equipped for it, you might find that your dog can not run alongside you. That does not mean, however, that you can't enjoy a bike ride together. For small dogs (which shouldn't run alongside you anyway) one can purchase bike baskets. For larger dogs, there are also trailers and side cars that can be used to carry your dog with you. 
Visit a veterinarian. Equip yourself. Equip your dog. Foster a positive association with the bike. Bring the bike along for a walk. Teach your dog important cues. Choose a location. Start out slow and short. Increase the time and pace. Watch for signs of heat stroke. Carry your dog. 