I didn't weigh them but the Boca yellow seals are about half the weight of the stock Losi bearings.
Also, for the clutch I usually just use the $1 version of bearings. Ceramics work fine here but they can and will fail just like any other bearing. With the $1 bearings if the clutch comes apart then it gets new bearings. Not too expensive and I haven't had a clutch failure for a long time. Knock on wood.
