Environment, economy and protective gear
The final domain links three practical things: how your riding affects the environment and your wallet, and what you should be wearing when something goes wrong.
Riding economically and quietly
Smooth, anticipatory riding beats hard acceleration and late braking for both fuel use and safety. Keep tyres at the correct pressure (soft tyres cost fuel and grip), keep the chain clean and correctly tensioned, and keep the engine serviced. Unnecessary idling is prohibited - switch the engine off while waiting. A standard, legal exhaust keeps noise down in residential areas and keeps the machine legal.
Running costs
Budget for consumables, not just fuel. On a 125, tyres, chain and sprockets and brake pads are the frequent items, on top of insurance (third-party is compulsory), the annual road fee, periodic inspection, and any tolls on your route - many Norwegian toll stations exempt motorcycles, but check locally. Illegal tuning or a non-approved exhaust can fail the inspection, invalidate insurance and cost far more than it saves.
Protective gear
A helmet is compulsory for rider and passenger and must be ECE-approved and fastened; replace it after any drop that hits the shell. Add gloves with knuckle protection, a jacket and trousers with CE armour at shoulders, elbows, hips and knees, boots with ankle support, and a back protector or airbag vest. Bright colours and reflectives help drivers see you. Gear does not prevent the crash; it decides how much of it you walk away from.
Worked example
8,000 km a year at 3.5 l/100 km and 20 kr/l is about 280 litres, or 5,600 kr in fuel. Add roughly 6,000 kr insurance, 2,500 kr tyres, 1,500 kr chain and sprockets and 3,000 kr servicing - around 18,500 kr a year before tolls. That is why a well-maintained, standard bike with good gear is the cheap option, and it is the reasoning an economy question expects.
Traps
Buying a cheap, badly fitting helmet; counting only fuel as the cost of riding; fitting an exhaust without updating the registration document.