I will be going there and back, and ideally can try 2 routes. Has anyone taken any of these roads? They all look interesting from the map view.

For reference:

Been in and around all those roads over the years in the truck.

Went in one way and completed the loop out.

Was in Prachuap Khiri Khan city last year all the roads were good.

Did the same trip last year from Pattaya down to Khao Lak....stick to the highlighted (and shortest) one roads are (were) fine

Went one way 4006 and back the other way 4 this year in March, all good, a bit of road work before Ranong, and a bit on 4006, but not an issue, good roads generally...

 

Been on 401 two weeks ago, from 41 to West is a lot of traffic and narrow , but after 40km or so it's very nice, and in the mountains nice views...

 

Can stop below, cave is nothing but they take you on small trip on raft in the small river behind for 80b, looked fun if have time...!

 

Pla Cave
Phanom, Phanom District, Surat Thani 84250, Thailand

https://goo.gl/maps/K4tRd1DsUtpKA4fh9

 

On 12/18/2020 at 9:01 AM, revgreen said:

For reference:

I did this route on bike start of november, great road.

 

Make you you visit Sam Roi Yod, very cool scenery, can't exactly remember where, i think just south of Chumphon.

 

For a motorcycle trip would recommend the route you've outlined in blue , Turning right onto the 4006 will take you along a quite stretch of twisting road with great scenery. Joining route 4 also takes you along winding hillsides that allows you to shift around on the bike keep things interesting and helps prevent sore limbs.  

No way.....this one is the best track...i did it last september, bankrut to Ranong 

 

App Maps.me and choose "by cycle"

Leg 1,

I took the 4 directly from Chumphon to Khao Lak (the 6h 29m route in my OP). Amazing stretch of road, but there was construction a bit before and then again after Ranong. Otherwise it was perfect. Little traffic, no trucks, nice scenery, fun curves.

 

Leg 2

Returning from Khao Lak to Chumphon I took the 4 up to the 4006 and then cut over to the 41 (the blue route in my OP).

The 4006 is NOT good now - lots of construction and heavy trucks/machinery.