Mattshreds

@ethaneggert42: What were the axle path and kinematics you were going for? It looks to me like this would have a rearward axle path and need an idler to have reasonable pedaling/suspension independence. Props on the build though, this is a stunner!

More mass probably does not equal slower, it equals less acceleration- practically negligible for a long, constant grade climb. This is assuming force is constant and considering that force= mass * acceleration. The effect of chain length should probably also be considered, as rotational energy is dependent on the inertial energy storage which is dependent on radius squared. Furthermore, speed is not linear with power. Newtonian drag is Force = drag constant * velocity, and power is force * velocity. So power should be proportional to the velocity squared. With that in mind, it seems that the power loss is mostly coming form the inertial effects of the extra long and more massive chain (as well as the idler bearing drag). This would result in slower acceleration of the drivetrain over each pedal stoke, equating to less linear velocity of the bike. Now its also interesting to note that more drivetrain inertial energy storage is advantageous in rough terrain, where it will allow for torque smoothing and more average torque transmission. The chain friction should be negligible, as the chain still completes the same angular displacement, but at a lower angular velocity - thus we have opposing affects of lower kinetic friction per link, but more links. That only leaves the drag of the idler bearing itself. Seems to me that pedaling ability is more than justified by the speed that will come form pumping on a proper rearward axle path design. Just my 2 cents. Cool to see somebody actually measuring these differences