If you plan on riding long distance low-carb, then you will also have to keep your intensity much lower. The reason for this is that fat fuel is much slower burning then carb fuel. High glycemic carbs provide instant energy but they don't last very long... fat is slow release fuel but also much longer lasting then carbs . It's very easy to deplete all the glycogen stores very fast. OTOH your body has enough fat stores to provide energy for many days. If you never done this before then start of easy, it takes a bit of time for your body to adept and reprogram itself to using fat instead of carbs for energy, first few rides may be a bit of a shock your system. Don't cut out all the carbs from your diet because it will affect your athletic performance too much, you can eat about 100-200 grams of healthy carbs and still loose weight, just avoid junk carbs.