Effectiveness of vibration damping with bicycle suspension systems

Bicycle suspensions aim to improve riding performance and rider comfort through reduced impact and vibration transmission to frame and rider. This study compared vibration damping of five mountain bike suspension systems and a rigid fork on gravel and in trail conditions by quantifying accelerations at the axle and frame. Spectral analyses of the acceleration signals revealed two distinct frequency regions from 0 to about 100 Hz and from about 300 to 400 Hz. The various suspension systems were all effective in attenuating vibration over the low frequency region. Vibration amplitudes at the frame were considerably less than at the axle for the suspension conditions (30–60% reduction) while only minor attenuation was observed with the rigid fork (10–15%). In the high frequency region between 300–400 Hz, the signal was strongly attenuated at the frame for all conditions, including the rigid fork. Trail conditions elicited greater amplitude low frequency vibrations than did gravel conditions. While all suspension systems were somewhat effective in reducing vibration of the frame, air-oil forks had significantly better vibration attenuation than did elastomer or linkage systems.