We test and review fitness products based on an independent, multi-point methodology. If you use our links to purchase something, we may earn a commission. Read our disclosures. Mountain biking isn’t exactly known for being a cheap sport. Top-tier road or exercise bikes can cost as much as a used car, with plenty of models sporting price tags of $10,000 and above. This is enough to discourage any budget-minded rider from participating in this outdoor activity.