water pump

[beshr]

pleas can you help me i have two question
1)what is the water pump reduction ration , and what is mean by redaction ratio 85/41 for example ?
2)what is the water pump impeller tilt limit ?

[Jonny Rochester]

1) In many car engines, the water pump is mechanically driven from the crankshaft by a rubber belt external to the engine itself. From car engines I have seen the water pump would have a similar speed to the crankshaft, often a bit faster. In bike engines, the waterpump maybe driven
from the crankshaft via a little chain and sprockets inside the sump. Due to higher rpm of a bike engine, the waterpump maybe underdriven or at slower speed than the crank.

[Jonny Rochester]

2) This is just a guess, but for a particular impeller, there would be a maximum speed you can effectively run due to cavitation at higher speeds.

[beshr]

aha thank you a lot