Table of Contents
What is the relation between stroke length and crank radius?
| Q. | The relation between stroke punch s and radius of crank r is |
|---|---|
| B. | s=2r |
| C. | s=4r |
| D. | s=r/2 |
| Answer» b. s=2r |
What is the relationship of the crankshaft throw to the length of the stroke of the engine?
The throw is the measurement from the center of the crankshaft to the center of the crankpin journal, which is used to determine the stroke of an engine. The throw is equal to one-half the stroke. The longer the throw, the greater the stroke, or distance, a piston travels.
What effect does increasing the stroke length of a piston have on an engine?
At a given engine speed, a longer stroke increases engine friction and increases stress on the crankshaft due to the higher peak piston acceleration. The smaller bore also reduces the area available for valves in the cylinder head, requiring them to be smaller or fewer in number.
What is stroke length of a piston?
The stroke length is how far the piston travels in the cylinder, which is determined by the cranks on the crankshaft. This number is multiplied by the number of cylinders in the engine, to determine the total displacement.
What is the crank radius?
The distance between the center of the main journal and the center of the crankshaft pin is called the crank radius , also called the crank throw . The front end of the crankshaft, sometimes called the nose, is a shaft which extends beyond the crankcase.
Why use longer rods?
Longer rods can improve rod stroke ratio, reducing thrust loading on the piston. Many racing engines use longer connecting rods to help reduce piston weight while having positive effects on torque curve shape and positioning and combustion efficiency. Longer rods typically require shorter, lighter pistons.
How is engine stroke length measured?
Ensure the piston is at the bottom of the cylinder. Measure the distance of the cylinder from the piston at the bottom to the top. This distance the piston travels gives you the cylinder stroke.
Does longer stroke make more torque?
Instead, long-stroke engines produce higher torque at lower RPMs. For example, the Sportster produces 73.2 Nm of maximum torque at 3,750 RPM, while the Street Triple produces 78.6 Nm at 9,350 RPM. A longer-stroke cylinder usually has a narrower combustion chamber.
What does a longer stroke do?
A long-stroke engine is an engine that has a smaller bore than its stroke. So the Bore to stroke ratio is less than 1. For a given engine speed, a longer stroke increases engine friction and as a result, increases the stress on the crankshaft.
How is crankshaft stroke length measured?
Stroke length is determined by the crankshaft….- OR –
- Install dial caliper (jaws upward) on the deck bridge.
- With piston at TDC, place bridge over cylinder.
- Zero dial calipers on the piston deck.
- Rotate the crankshaft until the piston is at BDC.
- Open dial calipers until depth rod is contacting piston deck clearance.
How is crankshaft stroke measured?
Total stroke can be calculated as twice the distance from the centerline of the crankshaft to the centerline of one rod journal. Increasing the stroke increases the swept volume of each cylinder and enlarges an engine’s displacement; decreasing the stroke reduces the swept volume and lessens the engine’s displacement.
What is fillet radius in crankshaft?
The Fillet Radius & Narrow Bearings On a crankshaft, The area where the bearing rides is called the Journal. The surface of the counterweight is called the Cheek. The Fillet Radius is the area where these parts meet.