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On my RK the front is a 130/90 R16. The SG front wheel has a 130/70 R18. Will replacing the used up SG tire with one of the same size work well on the RK with everything else remaining stock (fender, spacers, brakes etc)?
Like bigskyroadglide says "no worries", but if you're interested in the reason "why"... the 130/90B16 and 130/70B18 have virtually the same OD (Outside Diameter)