Kolkata to Moregram : Butter smooth four lane till Burdwan. Once you get to Norja more after squeezing yourself through the city lanes some good two lane roads , along with some partly rough patches start, this continue for quite some time till the road construction work in progress and gets further bad till you connect to the highway post Moregram .

More Gram to Malda: Roads remain butter smooth for some time and then slowly truckers join in for the party till they choke at Farakka barrage, road work is underway at few places, mainly on the Farakka-Malda Sector which makes it a horrible stretch to ride at night. Not many ameneties too alongside for refreshments. If it starts raining, then its like adding a cherry to the cake.

Malda-Raiganj: Traffic prone but not as bad as the previous stretch. Road conditions also get better.

Raiganj-Dalkhola-Siliguri:Siliguri-Kurseong-Pankhabhari-Manebhanjang : You would encounter traffic getting out of Siliguri, once you get into the Military area, the relaxed nature kicks in, roads start getting better and better. Kurseong was jam packed with tourists who are reluctant to give space for the vehicles. Kurseong to Dudhia is a nice not so trafficky route. Dhudia to Manebhanjhang roads are pretty good and starts to get better once the climb starts. But downhill coming jeeps can be distraction as they come with pin drop silence.
Typical 4X4 route. The initial climb is pretty steep and then the bad roads /no roads start. Do not attempt to do it on a 2W drive vehicles you would turn out to be a hinderance for other road users and the Land rover guys show no mercy as it is difficult for them too, to gain momentum from standstill. It is difficult, no doubts on that, make sure your vehicle is in a good condition as once you start the climb, the land rovers are probably the only help you might get. You are virtually into a no Help zone. The last 3 kms from BikeyBhanjang get progressively steep and bad. It will be quite a tiring stretch no matter which mode of transport you prefer. From Meghma, the road splits into two, one goes on the Indian side and the other from Nepal. The Indian side is much better than the latter. Worst part , you need to pay toll to use the Nepal side.

Manebhanjang to Darjeeling: Overall good roads. But from Ghoom you might feel claustrophobic w.r.t tourist traffic at Darjeeling.

Darjeeling-Jorethang (via Pattabong) : Initail few kms are average but pretty steep decline. Post that its bad roads all the way till Jorethang CP
: Initail few kms are good. But after nayabazaar, road widening is underway, so at some sections the roads are literally ripped open. It will take about a year atleast for it to be fixed, all depending on rains. After Leg ship the roads get better to some extent, but then again, certain sections are bad.

Pelling-Darap-Rimbi-Khecheopari Lake-Kanchejunga Waterfalls: Roads are overall Good, with some rough patches , but nothing to worry about .

Pelling-Sardong-Dentam- Singashore Bridge: Roads are overall good, but narrow.

Pelling-Legship-Ravangla-Sangmo-Tarku-Singtam-Ranipool-Gangtok: Overall roads are Average to Good, Till Ravangla, due to minor landslides, roads can be Average to below Average. Post Singtam, roads are good all the way till Gangtok.
Gangtok-Nathula-Gnathang valley: average to below average roads till Changu lake. After Changu roads are pretty good, unless there are landslides. Serathang to Kupup, roads are narrow but decent. There are 2 routes to Gnathang valley, one which is steep descent through army areas and the other longer one. The longer route is scenic and gives a better view of the valley, comparatively.
Gnathang Valley-Zuluk-Phadamchen-Rongli-Rorathang-Rangpo : Apart from landslide zones, roads are pretty good and scenic.

Rangpo-Melli-Kalimpong: Good roads.

Kalimpong-Labha-Algarah-Sillery Gaon-Pedong-Reshi : Roads are pretty good from Kalimpong to Algarah. After the diversion for Sillery gaon, all the way till the view point, its bad roads. Algarah to Reshi pretty good roads, apart from 2-3 areas which are landslide prone.

Reshi-Aritarlake-Rhenack : Bad roads for most part of it.

Algarah-Lava-Gorubathan-Damdim: Road widening underway at many places, so can expect it to be slushy/Dusty for most parts of it. Once you get down to the planes, roads are good.

Damdim-Malbazar-Chalsa-Jalpaiguri-Fulbari-Islampur: Good roads overall, but traffic gets exponentially higher from JLP and extends till Ghoshpukur. Once you enter Islampur, the roads get squeezed from four lane to lane with crazy truck traffic.

Islampur-Purnea-Bhagalpur-Rajoun-Hansdiha: One simple note , AVOID AVOID AVOID. It was a crude mistake from our end, intended to take Bhagalpur-Amarpur-Deoghar route and in Bhagalpur chaotic traffic somehow slipped into rajoun route .Potholes as big as 2 Fortuners(or may be even bigger). The ride/Drive can be very taxing.

Hansdiha-Dumka-Masnjor-Suri : Roads are much better than Bhagalur-Hansdiha route but more dangerous. Because of better roads we tend to do better speeds to make up for the time, at such critical point, killer potholes exist. It can make the rider and the bike do a somersault, if lack of attention.

Suri-Shantinikentan-Burdwan : Overall good two laned roads.

Burdwan-Kolkata: Good Four lane roads.