crankpin

The design was a series of counterweights opposing the crankpin.

This meant that there was no offset between the cylinders, and the crankpin did not have to be unusually long.

In a radial engine each crankpin serves an entire row of cylinders.

Most V-twin engines have a single crankpin, which is shared by both connecting rods.

In a multi-cylinder engine, a crankpin can serve one or many cylinders, for example:

In a straight (parallel) or flat (boxer) engine each crankpin normally serves just one cylinder.

The main connecting rod is a large triangular frame, driven by both cylinders and driving the crankpin.

Material specifications were different as were the detail design of internal parts such as the crankpin.

Crankpin and engine shaft nut key.

"The crankpin shattered," he explained.

In a V engine each crankpin usually serves two cylinders, one in each cylinder bank.

If a crankpin serves more than one cylinder, then the corresponding cylinders may have an offset, to simplify the design of the big end bearing.

Each half had its own crankpin, 180 apart, with the connecting rods,of chrome nickel steel, broad and flat to bring the two halves close together.

The fatigue strength of crankshafts is usually increased by using a radius at the ends of each main and crankpin bearing.

Then from 1982 the Jota 120 was released which had the crankpin phasing to 120 .

It uses a rocking sector whose motion is driven via a link from a crankpin between the coupling and connecting rods.

If a crankpin serves only one cylinder, then the big end is a relatively simple design, accommodating only one connecting rod.

Using a crankpin that is 'split' and offset by 30 of rotation resulted in smooth, even firing every 120 .

True boxers have each crankpin controlling only one piston/cylinder while 180 engines, which superficially appear very similar, share crankpins.

A week later at Albi, France, Jock West was in the lead when a crankpin seized and locked.

The crankshaft was a flat plane with three bearings and four throws, each pair of cylinders sharing a master-slave connecting rod onto the same crankpin.

This is achieved by changing the ignition timing, changing or re-timing the camshaft, and sometimes in combination with a change in crankpin angle.

Such a 'split' crankpin is weaker than a straight one, but modern metallurgical techniques can produce a crankshaft that is adequately strong.

Originally fitted with a crankshaft with 180 crankpin phasing and ignition timing on the righthand side of the engine till 1982.

A feature of this engine was the shared use of a single crankpin for both cylinders, this caused vibration as the pistons moved in the same direction.