IIRC, the first-generation Pacenti PL23 weighed under 400g. But those had a weight limit and were somewhat notorious for cracking. My spare second-generation SL23s are about 406g, but the brake track is kinda thin (1.1mm). 425g is probably close to the minimum for for an aluminum rim that is robust and won't wear out quickly.
I bet you'll notice much more of a difference with extra light Loup Loup Pass than a couple grams either way on the rims. Not just in the weight of the tires, but the lower-resistance sidewalls and tread that isn't overly thick at the edges.
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Originally Posted by
chandltp
There's no such thing as too far.. just lack of time
Originally Posted by noglider
People in this forum are not typical.
RUSA #7498