The Hebrides offers great potential for the bicycle tourist. The islands are accessible and yet feel very different in character to the mainland.
The roads are generally excellent and quiet. Make sure you let motorists by at the passing places and your days in the saddle will be relaxing… A marked contrast to the mayhem you can encounter elsewhere it the UK.
However, cycling these islands is not without its challenges, the biggest of which must be the weather. I had superb conditions for much of my trip this year, but my early pedaling on Barra and the south Uists gave a hint of jut how harsh conditions can be. Had I been cycling north to south into the wind, progress would have been slow and difficult. There are several accounts on the web of people riding these parts where trips have been abandoned due to frankly atrocious conditions, even in the summer.
The rule of thumb should be: always have a plan b. In my case, I had researched alternatives to camping had conditions been foul. This preparation extended to clothing. I washed and reproofed waterproofs, took a strong, weatherproof tent, had warm clothes for the evening while ensuring I had a dry alternative set of clothing at all times.
Simply put: prepare for the worst, but make sure you have some suncreen just in case you are lucky.