A type of internal combustion engine where all of the cycles of combustion occur in one 360 rotation of the crankshaft.

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8
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3answers
453 views

Starting a 2 stroke jet boat after several years

The parents in law gave me a jet boat, it hasn't been started in 5 years. The boat resided in NH on a trailer on their yard for 5 years, so it has seen freezing temperatures frequently. From what I ...
13
votes
4answers
628 views

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

It is a commonly-held belief that two-stroke engines are less fuel-efficient than four-stroke engines, and some example BSFC figures appear to confirm this as well. But what is it that causes ...
22
votes
2answers
2k views

Why do two-stroke engine exhaust pipes look so strange?

Two stroke gasoline engine exhaust pipes are shaped strange. They expand into a wide diameter and then shrink down to a very small diameter where the exhaust gasses emerge into the environment. Why ...
7
votes
2answers
68 views

Honda R8X-S heat seize

I've got a Honda R8X that heat seizes when I'm riding it when it goes over 40mph. The lad I got it off said he had it re-bored and that it was run in. Will I need to re-bore this again or is there ...
7
votes
2answers
522 views

Two-Stroke Diesel Engine - Do they use forced induction on them?

As I have indicated before, I'm very diesel ignorant. I just know the basics, very basics. In a two-stroke diesel engine using forced induction seems necessary but at the same time I see challenges. ...
6
votes
1answer
159 views

Two-Stroke vs. Four-Stroke Diesel Engines - What is most commonly used in heavy vehicles?

I am not well versed in diesel engines. To prove my point, I've learned in the last month that a two-stroke diesel engine actually exists. My Question. What kind of diesel engine (four-stroke or ...
3
votes
1answer
87 views

JLO Rockwell 2F600

I have an old hovercraft that uses a small aircraft engine in the front to power both the lift and forward propulsion. I was hoping to find any kind of manual or literature on the engine itself. The ...
1
vote
0answers
192 views

2 cycle engine has spark and new carb won't start [closed]

I have a 49cc 2cycle engine that I replaced the carb on. It has fresh gas and appears to have a spark. I can't get it to fire even if I put some starter fluid in the air intake. It seems to have ...
4
votes
1answer
410 views

Old gas in 2 cycle engine

I have a 2 stroked engine that sat for over 2 years. I drained the gas and can get it to turn over when I put starter fluid in the carb. it is blowing out a water substance from the muffler and cuts ...
4
votes
2answers
891 views

Single Cylinder 2 stroke bike with twin exhaust, will it need two chambered exhausts?

I am asking specifically about Yezdi (not in production anymore) 250/350cc motorcycles. Yezdi RoadKing was a 250cc single cylinder two stroke with twin exhaust. If upgrading to a calculated chambered ...
6
votes
1answer
541 views

Two-stroke dirt bike piston running into spark plug

Recently, I submitted a post on here regarding a broken ground electrode on the spark plug of my 2005 Suzuki RM125: Bottom piece of spark plug broke off in motorcycle engine Well, I found out what ...
10
votes
1answer
493 views

Does the air screw only affect the pilot jet?

I have a 2 stroke motorcycle, it's Kawasaki KR150. When I try to do some jetting on its carburetor (it's Keihin PWL26), I saw that there's an air screw. So now I've been wondering about this air ...
0
votes
1answer
499 views

2 stroke scooter won't rev under load

Just put a big bore kit on a Yamaha Jog (50cc to 70cc) and am getting ~115psi compression. It will reach full rpm on the stand but on the road it won't pass mid throttle and makes a hollow/rattling ...
2
votes
1answer
4k views

What is the difference between a 2T oil and a 20-40 oil

I know a 2T oil is used in 2stroke bikes and its sometimes added with the fuel too. And a 20-40 oil also known as the engine oil is used to reduce the wear tear in the engine. I'm looking for a ...
3
votes
3answers
813 views

Derbi Senda 50cc - Low Compression, will not run properly

I have a Derbi Senda SM 50 2005 plate. It has a good spark, however, it's not reading any compression. It's had a new top end and gaskets! What could be wrong? Sometimes it starts when you bump ...
3
votes
1answer
1k views

Small two-stroke engine runs poor

I have a borrowed cultivator (Echo TC-2100), and having hard time running it. It looks fairly new, and in good condition, but was possibly poorly stored and was not winterized. At first I could not ...
8
votes
5answers
3k views

What are the problems in building 2 stroke engines with a large displacement?

I understand (from preliminary research) that when engine gets bigger, with a higher displacement that it is practically not possible to have a two stroke engine. What are the implications in ...
7
votes
3answers
1k views

Is it okay to run aviation fuel (100 low-lead) in a dirt bike?

I'm wondering if it will be okay to run 100 octane low-lead aviation fuel in my 2007 RM250 motocross bike (two-stroke). Half of the people I've asked say yes, while the other half say no. Will it be ...
15
votes
1answer
3k views

What is happening when a two-stroke engine is said to be “four-stroking”?

Many years ago, I was involved in a hobby of building and flying model aircraft. The aircraft used alcohol-fueled 2-stroke engines with glow plug ignitions. When these engines ran rich (and always at ...
4
votes
3answers
2k views

Two-stroke engine won't start - water in gas?

I realize this isn't a car question. There doesn't seem to be an appropriate Exchange for it, so I'm trying it here. I have a two-stroke engine (for a rototiller), and it worked more-or-less well ...
1
vote
1answer
2k views

50cc Two Stroke Scooter/Motorcycle - Idle and start issues

This is my first motor-vehicle ever, a Simson s50 from 1976. Things seem to be running fine, but there are two problems I need to figure out: 1) The engine dies unless rev'ed constantly - eg at a ...