What makes an impressive mountain bike?
Low-friction, optimal grip tires
A short introduction to mountain bike types
29er, race geometry (Überhöhung), suspension exclusively on fork, typically with 100 mm travel
+ maximum uphill performance, highest speed, best acceleration
- requires good driving skills, particularly on technical trails
mostly 29er but also 27.5, relatively low travel (100-120 mm) suspension on both wheels
+ still relatively good uphill performance, rear wheel suspension and geometry facilitate control on technical trails
- Much of a compromise
mostly 27.5, geometry promotes an upright seating position, relatively high travel (120-160 mm) suspension on both wheels
+ very good downhill performance, geometry facilitates control on technical trails, high jumps and drops possible
- long uphill passages are tough pieces of work
Downhill / Freeride:
mostly 27.5, saddle is so low that it is hardly useful for seating, extremely high travel (> 160 mm) suspension on both wheels, heavy duty, heavy
+ extremely good downhill performance, extremely high jumps and drops possible
- uphill? Where is the cable car? Heavy weight can be obstructive in technical passages.