The short answer
Take the Yamaha XMAX 300 if your riding is Bangkok and only Bangkok: it is lighter, smoother and slightly cheaper to run. Take the Honda ADV350 if you leave the city, because the longer travel suspension and the block pattern tyres are the difference between enjoying Route 323 to Kanchanaburi and counting potholes.
Status, up front: both show no dates available at NOIRR. Neither is in the fleet yet, so booking is not open on either. The reference rates for when dates open are ฿1,100 per day for the XMAX and ฿1,400 for the ADV350. Get notified when dates open. The one NOIRR two wheeler you can book today is the Ducati Monster 937 at ฿3,500 per day.
The numbers
| Honda ADV350 | Yamaha XMAX 300 |
| Engine | 330cc single, eSP+ | 292cc single, Blue Core |
| Power | About 29hp | About 27.6hp |
| Torque | About 31.5Nm | About 29Nm |
| Kerb weight | About 186kg | About 179kg |
| Seat height | 795mm | 795mm |
| Fuel tank | 11.7 litres | 13 litres |
| Underseat storage | About 48 litres | About 45 litres |
| Electronics | ABS, HSTC traction control, adjustable screen, Smart Key | ABS, traction control, adjustable screen, Smart Key |
| NOIRR status | No dates available | No dates available |
| Reference rate | ฿1,400 per day | ฿1,100 per day |
On paper they are close. In Bangkok they are not, and the reason is the suspension, not the engine.
The expressway rule that neither of them passes
Motorcycles of 400cc and above are permitted on parts of the Bangkok expressway network, including the Chalerm Maha Nakhon and Si Rat expressways. The ADV350 at 330cc and the XMAX at 292cc are both under the line, so both leave the city on surface roads. On a run to Ayutthaya or Kanchanaburi that is 20 to 40 minutes of extra traffic in each direction.
The Ducati Monster 937 clears it easily. If the expressway matters to your plan, the choice on this page is not really between these two scooters.
In the city
The XMAX wins narrowly. Seven kilos lighter is noticeable when you are filtering along Sukhumvit between Asok and Thonglor at walking pace, and the lower seat feel plus the flatter floor makes it the easier one to paddle backwards out of a condo car park. Both have enough underseat space for two helmets or a full grocery run.
The ADV350 is taller in the wind and the five position screen actually works, which matters on Rama IV and Vibhavadi where you sit at 80km/h for long stretches. It also has HSTC traction control, which earns its keep on the painted road markings and steel plates after Bangkok rain, and both bikes have ABS.
Outside the city
The ADV350 wins clearly, and it is not close. Longer travel suspension, more ground clearance, block pattern tyres. On Route 323 into Kanchanaburi the road edges break up after heavy rain, and on the ADV that is a non event while on the XMAX it is a constant negotiation. Same story on the unsealed approaches to viewpoints and waterfalls where every good day trip ends.
The XMAX is the more comfortable of the two on smooth highway, so if the plan is Bangkok to Hua Hin on Rama II and nothing more adventurous, it is fine.
Running costs
Both do roughly 30 to 35 kilometres per litre in mixed Bangkok riding. The XMAX carries 13 litres against 11.7 on the ADV, so it goes slightly further between stops. At NOIRR reference rates the ADV350 costs ฿300 per day more, which is ฿2,100 over a week, and the honest question is whether you are genuinely leaving Bangkok. If you are not, the XMAX is the better value.
Licence and documents, both bikes
Both are over 50cc, so both require an International Driving Permit with the motorcycle class (Category A) or a Thai motorcycle licence. A car only IDP does not cover either and your travel insurance follows the same rule. Helmets are mandatory for rider and pillion and are enforced.
What happens next
Both scooters show no dates available. They are not in the NOIRR fleet yet, so booking is not open. Leave your email on the one you want and get notified when dates open, and NOIRR emails you the day it changes, once.
If you need two wheels in Bangkok this week, the Ducati Monster 937 is on the road at ฿3,500 per day, delivered, with a refundable cash or card deposit and no passport held. It is a very different bike and it is not a beginner machine, so read the big bike guide first, then pick your dates.
In Thai: เทียบ ADV350 กับ XMAX 300 สำหรับกรุงเทพ.