I guess I would also have to ask everybody if there is a schrader valve 28C tube available. No sense in buying 28C tires if there are no tubes made for my rims. I do want to keep the 36 spoke rims I'm currently using. I need strong rims.
My wife has Sefras Seca 700x28c tires on her KHS Vitamin B and her tubes or "marked" 700x28-32c and are"schrader valve", it seems, most shops carry this size and style of tube, FYI. I know Performance Bicycles carries them as I bought a "spare" for my wife last week. PS: the rims on her bike are "marked" for 700c, sizes 28-38.
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Take Care, Ride Safe, have FUN! :)
Jo: 2009 ICE Trice T
BJ: 2011 ICE Sprint Special Edition