Sigeyi makes a very lightweight power meter. The Sigeyi AXO Power Meter Spider weighs between 83 and 115 grams, based on the version ordered. The MTB version weighs 83 grams which is the least as it uses a slightly smaller 104 BCD. The 110 BCD road version is next at 105 grams, followed by the 130 BCD road version at 115 grams. By comparison, this is approximately 40 grams less than other spider based power meters made by power2max, SRAM, Quarq and SRM.
Sigeyi AXO Power Meter Spider