A variable valve timing(VVT) mechanism with switching cam is developed on a motorcycle engine with single overhead camshaft.The VVT mechanism has two sets of switchable intake valve timing parameter.

• 摘要在摩托车发动机单顶置凸轮轴配气正时机构的结构形式基础上，研制一种可切换凸轮型线的VVT机构，具有2套可切换的进气配气正时参数。