The BOB is carrying it's own weight, so there's not much added weight on your bike. Consider the road surface as to whether you need wider tires. If you're pushing the limits now, then stepping up a size might make sense, but if you're riding at 100-110 psi and not getting pinch flats now, then you probably don't need to make any changes.dodi said:I'll be pulling a BOB trailer when we do a week long trip to San Juans/Puget Sound in a couple of weeks. How wide should I go? There will also be riding without the trailer, so I wouldnt want it to hinder me when we climb Mt. Constitution or other rides.