Dual Sport OHVs refers to off highway vehicles that have been enhanced to meet street legal requirements so they can be used both on and off road. A few OHVs are available from the dealer or factory as dual sports but most times you have to install the modifications yourself -- or have your dealer do it to make an off road vehicle street legal. Whether or not a particular vehicle can even be made street legal will depend on local (state) regulations and representations of the manufacturer.
Why would you want a dual sport vehicle? Sometimes it is convenient to be able to ride your off road machine on public highways. You may want to ride to a store to pick up supplies or parts. Sometimes there are no connecting trails between OHV routes you want to take. Having a dual sport machine allows you to legally ride on the highway from one trail to another. There are even organized dual sport rides that are specifically designed to include both on and off road segments. Sometimes you may just want to add lights to an OHV that has none, just in case you're late returning from an afternoon ride. I was once with a group of about a dozen or so riders who ventured further than they had planned and didn't get back to camp until after 10:00 pm. We only had about 4 bikes in the group that had headlights so we had to space them out to each lead a few unlighted bikes. It was slow going and very frustrating and sometimes even frightening for the riders that had no lights. One of my Desert Rat buddies added a heavy duty lighting coil to his dirt bike to power a 55 watt automotive halogen driving light for a head light. Man! That thing really lit up the desert. Fellow riders dubbed it the "bush burner. You can buy universal light mounts that clamp to the front forks allowing you to mount just about any kind of light you want. I've also seen some innovative lights that mount beneath the handlebars to increase illumination on bikes with an ordinary headlight or add lights to one that has none. Note that neither of these lighting solutions would qualify for street use.
Making an OHV street legal mostly involves installing proper lighting and a horn but highway rated tires are also a requirement. Ordinary dirt tires are NOT street legal. There are specially designed "D.O.T" knobbies that are street legal and still provide pretty good off road performance. Die hard off roaders generally prefer the performance of real off road tires but unless you're a serious off road racer you probably won't notice the difference. Speedometers are also usually required for a machine to be street legal. That makes sense, since you must obey posted speed limits when operating your OHV on the street. You also have add brake light switches to both the front and rear brakes.
The first step in conversion is usually installing a "lighting kit". There are configurations that are especially designed to fit many of the most popular OHVs, making installation somewhat easier. If there isn't a kit made to specifically fit your ride, you can probably get a universal kit and make it work. You can have it installed by a mechanic or, if you are a fairly good back yard mechanic, you can probably do it yourself. Even kits made specifically for a given machine will most likely require you to do some drilling and maybe some cutting and you will probably have to provide your own hardware (nuts and bolts) for at least some of the modifications. The kit should include a brake light and switch, turn signals, and a horn. Some kits also include a headlight. If your ride already has a headlight, you might be able to use it. Some off road units come factory equipped with dual filament headlights, but only the low beam is hooked up. The conversion kit will include a high/low switch and wiring to make use of both filaments. If your machine already has a headlight that operates when the engine is running there will be modifications to the factory wiring to run the power for the headlight through the high/low switch provided in the kit. The little battery on many OHVs, especially dirt bikes, if they have one at all, isn't powerful enough to run headlights which consume a lot of current. If you have a battery, the horn, turn signals, and brake light will be connected to the factory installed battery. If you don't have a battery, your kit should include a small battery pack to power these items. Sometimes you have to add an upgraded lighting coil to the magneto in order to generate enough power to run headlights on machines that weren't factory equipped with them. The lighting coil may or may not be part of your lighting kit, so be sure to determine if you need one and if it is included. The installation of a brake light switch usually involves removal of one of the "banjo" joints in the hydraulic system so you will have to bleed the brakes after the switch has been installed. You should have brake light switches on both the foot band hand brakes. Speedometers aren't usually part of lighting kits so you may have to purchase one separately.
The entire installation of a lighting kit should only take a couple of hours, if you know what you're doing and have had some practice, but if you haven't done one before, allow yourself a lot more time. Even though I've installed lighting kits on more than one dirt bike,one I installed recently took most of an entire Saturday. Admittedly that included a trip to town to buy some bolts I needed to fasten on the rear fender modification that contained the brake light and onto which the rear turn signals mounted. Some aspects of the installation can be rather tedious and working the new wiring harness through tight spaces can be time consuming and frustrating. Make sure the wiring isn't going to get pinched or come in contact with hot surfaces like exhaust pipes. Secure it to the frame with zip ties to keep it in place where you want it. And take care not to pull any existing connections loose. The second identical installation only took a few hours.
Most of the dual sport machines I've see were motorcycles, but ATVs and side-by-sides are also sometimes candidates for being made street legal, especially if you plan to use them around a farm or ranch.
So-called "Street Legal" OHVs may have special restrictions when they are operated on public highways. For example, in Utah, an ATV that has been converted can only be operated on 2-lane roads and at the lesser of the posted speed limit or 45 mph. While this may seem like an arbitrary limitation, consider the fact that a number of ATV riders have been killed operating their ATVs on pavement. For one thing, the off-road type tires grab the pavement differently than highway tires do and can result in unexpected sensitivity to steering and to imperfections in the pavement, causing the vehicle to swerve or flip. D.O.T. rated tires will help improve on pavement performance but will still not be as stable as regular street vehicles.
Converting on OHV for dual sport riding will take some effort -- and/or expense. But I'm sure you'll discover it is well worth it.
Make it legal!