Here are some factors that can affect the top speed of a 350 cc quad:
* Engine power: The more powerful the engine, the faster the quad will be able to go.
* Weight: The heavier the quad, the slower it will be able to go.
* Tire size: Larger tires will provide more traction and allow the quad to go faster.
* Terrain: The type of terrain the quad is being ridden on will also affect its top speed. Quads will be able to go faster on smooth, paved surfaces than they will on rough, uneven terrain.
It is important to note that riding a quad at high speeds can be dangerous. Quads are not as stable as cars or trucks, and they can easily tip over if they are not ridden carefully. It is also important to wear a helmet and other protective gear when riding a quad.