If you're going to combine vodka and maple syruo, maybe you want to use maple liqueur instead, since it's pretty much the same - base alcohol(vodka) + syrup.
2oz Maple liqueur
1.5 oz sparkling cider
Combine equal parts cinnamon and sugar on a shallow plate and use to coat the rim of a cocktail glass. Add the maple liqueur to a mixing glass and fill with ice. Stir, and strain into the prepared glass. Top with the cider.
Vodka is great for diluting without decreasing proof, but is often unnecessary. It is great for approximating liqueurs or making your own liqueurs, as this recipe demonstrates.