As of October 2010, sections of the road after Balipara where you divert from NH52 is work in progress and you will find mud roads with stones which are unpleasant to ride on. After Bhalukpong, BRO is widening the roads so expect slushy roads for around 15 kms. If you love your motorbike, travel by a taxi/bus from Tezpur.
The town is about a 16 hour drive from Guwahati. However, it is best to hire a Tata Sumo from Tezpur in Assam 4 hr. drive from Guwahati. From Tezpur you go to Bhalukpong border of Assam and Arunachal where Indian and Non Indian tourists have to show in permit easily obtainable at either Guwahati or Tezpur and proceed to a beautiful and rough drive up the mountains. It can take 12-14 hrs if you go at a stretch to Tawang. It is advisable to break your journey at either Bomdila or better still - charming little valley town of Dirang. Sela pass is notoriously difficult and heavy snowfall during season could force you to stay on either side.