When you change Products prices it does not automatically reflects in the bundles. (This is because Salesforce does not support triggers on PricebookEntry object. Please vote for this idea to gain Salesforce attention: https://success.salesforce.com/ideaView?id=08730000000XnicAAC)
We are aware of this and hence we have Refresh functionality baked into the platform. Just click “Refresh” button on a bundle to reflect latest price, cost, margin, sales price, discount etc. On clicking this button all Bundle Item pricing will be updated as per the new price in the Pricebook. To refresh multiple bundles at one go, go to Bundles tab, select All in the list view, click Go, click check box next to Action column and then click Refresh.
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