What roads, distances.....
I used a 24 hp Royal Enfield Himalaya in Nepal.
It was perfect for that.
The roads and the traffic puts so much limit on the speed that you can travel.
That I never used those hp. But I liked the low end torque.
You do not have to change gear often and rev the engine.
I used a Moto Guzzi with 68 hp.
It was pergect for travelling in Europe with good roads. Two persons including camping equipment. 130 km/h crusing on larger roads.
I look for a 250 with 20 hp (or Himalayan) to drive gravel roads in Europe.
Where weight is more important than HP.
Travellling South America. 10-15 hp would be enough. Getting up those mountains. For example a Honda Cargo with 15 hp. And the luggage rack where the passenger normaly sits. A pizza delevery bike
https://www.honda.com.br/motos/cg-160-cargo
Or an Apache 160 cc with 15 hp
https://www.tvsmotos.com/motos/apache/apache-rtr-160
Simon used a 125 cc version of this with 12 hp around South America.
Ed used his C90 with 6 hp from Malaysia to UK.
I guess that below 3-4 ho it is no longer a bike. But a moped.
So there is mybe the limit.
If there is a limit at all
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But is also nice to go on a long trip adventure with 150 hp
If you have roads to use that
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