Originally Posted by
Murmur1979
Regarding efficiency, well that's an interesting subject. A few years ago, I remember finding several scientific studies which proved that a suspended fork is either more efficient or not less efficient than a rigid fork, even on roads (I should search for those studies again)..
How much does your full suspension bike bounce when you pedal? That bounce is wasted energy that could have been used to propel you forwards on a rigid bike. Your suspension units are easily 1kg each, so your full suspension bike is at least 2kg heavier than a rigid bike which is significant on a 15kg bike.
A lot of the rest of it is down to tire choice, riding position etc. A full suspension bike is naturally going to be more comfortable in terms of dealing with road surfaces, but it will take more work to cover a given distance, and won't be as comfortable in terms of body position over a longer ride.