KACTUS 17TSE Bicycle Rear Derailleur Cycling Carbon Fiber Pulley System

KACTUS 17TSE Bicycle Rear Derailleur Cycling Carbon Fiber Jockey Pulley Bike Bicycle Guide Wheel for SRAM ETAP Product: Carbon Fiber bicycle Derailleur Kit Material: Full Carbon fiber frame+bearings+7075 Aluminum Alloy Jockey Wheel(CNC) Color:Black Suit for : SRAM ETAP Features: 1. 17T Oversized Pulley Wheel System 2. Save 60% frictional resistance than 11T 3. Full carbon fiber cages 4. CNC AL7075 lightweight pulleys and axles CHARACTERS: According to test result, increase the rear derailleur pulley wheel size could significantly decrease the friction between the chain plates caused by polygon effects during chain bending, and reduce the resistance for saving rider's cycling power. The chain is composed of several short pieces with an inch long, we could see the chain as one inch long with around one hundred and ten section lines, due to small diameter of turning circle, when the lines pass through standard 11T pulley wheel, it needs a certain angle to turn the transferring direction of chain for about 180° through two wheels, after increasing the pulley wheel size, the chain turning angle are decreased, so the loss of friction is less correspondingly. The results shows that 17T is a good balance point between weight and decreasing the polygon effects, To increase the size blindly will lead to arc decreasing not obvious, together with weight and volume adding. Compared with common 11T pulley wheel, the friction loss caused by polygon effects of chai