I'm no bike mechanic but is it really a good idea to spray the chain with WD40 - it is very penetrative and will wash away chain lubricant. On an O-ring type chain it might even penetrate the O-rings. It might then be difficult for newly applied lubricant to penetrate the O-rings as lubricant isn't as penetrative as WD40, and some WD40 might remain inside O-rings further reducing the effectiveness of new lubricant.