China Supplier 30mm U Groove Nylon Roller Wheel - 18TX Oversized pulley wheel System – Kactus Sports

14/18T Oversized pulley system

Save up to more than 60% chain friction resistance

Ceramic bearing version save over 2.4 watts on average, compared to original transmission.

Full carbon fiber cage

Full 7075 aluminum alloy CNC lightweight pulley

18TX suitable for SHIMANO XTR/XT/SLX M9000/M8000/M7000GS/M6000GS 

SS RD convert to SGS RD

Ceramic bearing version hybrid ceramic bearing version NSK steel bearing version

Weight: 56g

Ceramic version weighs 1.2g less.

Why replace derailleur pulley

First, replace the original pulleys with these would improve the weak stretch of the original set, and make the up and down chain tension between guide wheel and cogs much more adequate.

Second, the number of contact tooth or control tooth between chain and cogs of 17T is more during gear shifting, the more contact, the stronger the control power.

Third, after redesign the cage’s rotation curve, the distance between upper guide wheel and the cogs is improved.

Long story short, with all the features mentioned above, you would save 2.2 watts or more with each pedaling. That’s the equivalent of shaving 100g off a 10KG bike.