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12 votes

Who came up with "suck, squeeze, bang, blow"?

This phrase has been around very long and has been used in the aviation industry as well as automobile. This is a very good, and more importantly, very easy for anyone to understand way of describing ...
JPhi1618's user avatar
  • 13.2k
10 votes
Accepted

Two-stroke vs four-stroke design

Depends. A key point of 2-cycle engines is that a thing called scavenging happens with the piston at the bottom: at the end of the power cycle/ beginning of the compression cycle. During ...
Harper - Reinstate Monica's user avatar
8 votes

What makes two-stroke engines less fuel-efficient than four-strokes?

The efficiency of any internal combustion engine is directly related to its Carnot efficiency, where efficiency equals the inlet air temperature minus the exhaust temperature divided by the inlet ...
Paul Ellis's user avatar
7 votes
Accepted

Do 3 and 5 cylinder engines have uneven power delivery?

You are thinking too linearly. A V8 engine has two connecting rods attached at each crank journal with a crank spacing of 90° between each crank journal. The I5 (like the GM LLR) has a single ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
6 votes

Two-stroke vs four-stroke design

For Two Stroke engine: One working stroke in each cylinder per revolution of crankshaft. Light in weight. Moving parts are few. Mechanical efficiency is more. Thermal efficiency is less because a ...
Dan Khan's user avatar
  • 169
4 votes
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Ignition timing of 4 stroke two wheeler

As Steve Matthews says, get your flywheel in a proper position, it shouldn't be able to fit it wrong way. Unless you have lost a part number 6 "keyway". To me looks like coil 3 is a high voltage coil ...
Arturs Bolsunovskis's user avatar
4 votes

Ignition timing of 4 stroke two wheeler

I would say that, almost certainly, the orientation of the flywheel relative to the position of the engine will be important. Looking at the diagram, I'd guess you physically removed part number 7 to ...
Steve Matthews's user avatar
4 votes
Accepted

Which engine type gives more HP- two or four cycle?

Theoretically, with all other factors being equal, the 2 stroke engine should produce 2 times the power of the 4 stroke engine. The reason being that the 2 stroke engine has twice as many power ...
jwh20's user avatar
  • 12.1k
4 votes

Two-stroke vs four-stroke design

Not sure if you count that under “besides the apparent”... but IMO the single most striking peculiarity of a two-stroke is that it uses both sides of the pistons to work on gas volumes†. That's what ...
leftaroundabout's user avatar
4 votes

Why does ignition occurs during the power stroke in spark ignition engines?

In normal running conditions, the ignition does not happen during the power stroke, but just before, at the end of the compression stroke, because it takes time for the burn to propagate through the ...
Weather Vane's user avatar
  • 2,314
3 votes

What is the difference between a 2 stroke and 4-stroke engine?

A 4-stroke engine will pass smog LOL. Engines take a volume of air, combine it with fuel, put it into a cylinder and then do two strokes: compression stroke and power stroke. The cylinder is now full ...
Harper - Reinstate Monica's user avatar
3 votes
Accepted

Why does ignition occurs during the power stroke in spark ignition engines?

While I agree for the most part of @WeatherVane's answer, it doesn't really answer your question: Why does ignition occurs during the power stroke in spark ignition engines and not during other ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
3 votes
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What are the dangers of too high TBN?

You might want to read the article here: TBN Discussion But the key point on too high a TBN number is: So should we all use a High TBN oil? There are advantages, but there are also ...
jwh20's user avatar
  • 12.1k
3 votes

Two-stroke vs four-stroke design

Yes, number of power strokes per revolution, less complicated : fewer moving parts, emissions or pollution levels. Have a look here : http://mechstuff.com/differences-advantages-disadvantages-of-4-...
Solar Mike's user avatar
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3 votes
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Starting fluid, does it require a spark or autoignite?

If the engine is cold, there is no way the combustion chamber is going to get up to 160 degrees C. even when the air is compressed. So your problem is with the fuel system; either the fuel pump, or ...
Mark Stewart's user avatar
2 votes

What makes two-stroke engines less fuel-efficient than four-strokes?

Very much depends on the particular 2 stroke and 4 stroke engines. But a major advantage of a 2 stroke is that they can be produced incredibly simply and so cheaply. An engine with 3 moving components ...
Kickstart's user avatar
  • 571
2 votes

What is difference between stock CDI and racing CDI in a 4 stroke motorcycle?

A CDI ignition system uses capacitors to charge up the energy for the spark plug discharge. Generally speaking, capacitors do this more quickly than electrical coils, allowing the ignition system to ...
tlhIngan's user avatar
  • 12.2k
2 votes

In a petrol engine, how does the first stroke happen when the gas pedal is first pressed?

Judging from your question, you are indeed new to mechanics. The pressing of the gas pedal does not start the engine. The engine is already running, disconnected from the wheels by a slipping torque ...
juhist's user avatar
  • 14.6k
2 votes

Oil sump for 2 stroke vehicles

So there are quite a few two stroke engines. For gassers like chain saws, the oil and fuel (gasoline) are mixed and introduced into the crankcase by the carburetor. The oil lubes the engine, and is ...
mongo's user avatar
  • 2,115
2 votes

Oil sump for 2 stroke vehicles

Because in a two-stroke, the air-fuel charge gets taken into the crankcase. If there were a sump of oil there, it would get sucked into the engine. There are many two-strokes where the oil is stored ...
Ceshion's user avatar
  • 1,698
1 vote
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Motor oil requirements on exhaust system

Oils have various additives. Some of the oils in 4 cycle oil form ash if they are burned in combustion; elements like zinc and barium . Because all the 2 cycle oil will be burned it is formulated with ...
blacksmith37's user avatar
  • 3,688
1 vote

Oil sump for 2 stroke vehicles

There are in fact two stroke engines that get lubricated by an oil sump / pump system and do not receive the lubricating oil through the air-fuel mix. Those are two stroke diesel engines used in ...
Martin's user avatar
  • 8,458
1 vote
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More difficult to start the MotorCycle

20 kicks is a lot, I'd expect 2 or 3 kicks should be enough to start a motorcycle. Looking at the slingshot specs it says it's a carbureted engine, not fuel injected, I suspect what's happening is ...
GdD's user avatar
  • 17k
1 vote

More In Cylinder Pressure Testing Questions

I did some searching on IATN and found known good pressure waveforms that are identical to my after repair captures. Unfortunately I can't post them here. It turns out that hump is completely normal. ...
Ben's user avatar
  • 10.7k
1 vote

What is the efficiency delta between rotary and modern four-stroke engines

I couldnt help but notice,the much bigger rotary "piston" surface/per amount of fuel, was being somewhat overlooked in these other answers considerations. It might be a compensating factor in ...
Hackenbacker's user avatar

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