The pepper spray I use is HALT, available at nashbar.com. It will not permanently injure a dog, just stop them in their tracks while you make your getaway. But yes, the wind can cause it to blow back into your eyes (or those of another rider) if you aren't careful, and sometimes you just can't get it out and aimed in time. Nashbar also sells (or used to) a little $2 clip to mount it on your handlebars (I think it fits drop bars only), which makes grabbing it much quicker. Yep, it's geeky, but it's helped me a couple of times. You can't spray it until the dog is quite close, though. Best for when you are going slow uphill and have no chance of outrunning the dog. Sometimes just pointing it at a dog is enough; most are instinctively scared of a pointed "weapon".
Another option that I invested in after my accident last April was an Air Zound airhorn. I believe I bought it at nashbar as well, but I don't think they carry them anymore - a web search would likely turn it up somewhere, though. These have an air chamber that mounts to your frame and a handlebar-mounted trigger to sound the horn. It is LOUD. If you use one, it tends to stop dogs in their tracks as well, and you don't need to wait until they are nipping at your heels to use it either. But tell any riding companions that you have one and before you use it if at all possible, to avoid startling them.
Dogs are definitely my biggest fear on the road. I also live and ride in a rural area where there are many unrestrained dogs (despite a county leash law), and as many of you know, two large dogs ran out at me from the side last April as I was riding. I had my HALT but could not get to it in time (and with more than one dog, it's of more limited use anyway). I sped up in an instinctive move to outrun them, while my husband (in front of me) slowed slightly to look back and see what was going on (I am sure I yelled "DOGS!!!"), and before I even knew what was happening, I slammed into his rear wheel. He was fine, but I crashed on my right side at fairly high speed, HARD, and fractured my pelvis in three places. It was very serious and required surgery and a long rehabilitation period. I have a 6" stainless steel plate and four pins in my ilium and will never be completely the same. The dogs ran away once I crashed. I am sure they just wanted to chase and have some "fun", but it was a very difficult experience.
It's good to hear everyone talking about this all-too-common road hazard. I think it's best to have a plan of attack when dealing with dogs - different situations require different tactics - and in addition to the dogs, don't forget to pay attention to other riders around you if you're not alone, since a bike-bike crash can be even more serious than a dog encounter!
Emily
Emily
2011 Jamis Dakar XC "Toto" - Selle Italia Ldy Gel Flow
2007 Trek Pilot 5.0 WSD "Gloria" - Selle Italia Diva Gel Flow
2004 Bike Friday Petite Pocket Crusoe - Selle Italia Diva Gel Flow