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two stroke vs four stroke...
Posted: Wed Aug 20, 2008 4:36 am
by nq50KillingSpree
how can i tell if i got a four stroke or a two? i think its a two stroke...i have a 1986 nq50 spree
Posted: Wed Aug 20, 2008 5:08 am
by 89D/OSpree
well firstly, all the 50cc sprees came out stock 2 stroke. if the motor was swapped out, here is how you can tell if it's a 2 or 4 stroke. mixing oil with gas whether you pre-mix or the engine does it for you is a 2 stroke. 4 stoke uses oil as a lubricant as well however, it does not mix with the fuel. 4 stokes also have radiators, 2 strokes usually don't unless it was modified (usually stroker bores). another way to be sure is the sound. if it sounds like most mopeds than it probably is a 2 stoke. a 4 stroke sounds more like a street bike. And then there is the smell of the exhaust. 2 strokes smell like weed whackers, chainsaws, dirt bikes. 4 strokes don't.
Posted: Wed Aug 20, 2008 5:43 am
by nq50KillingSpree
thanx for that!!
Posted: Wed Aug 20, 2008 2:12 pm
by Kenny_McCormic
Sprees are 2 stroke they use 2 stroke oil and the above statement is mostly wrong.
Posted: Wed Aug 20, 2008 3:58 pm
by Elite1998
Its a two stroke. You would know if it was a four stroke because the acceleration would be slow and by how it sounds..let alone if the gas+oil mix which also creates a stronger smell from the exhaust
Posted: Wed Aug 20, 2008 8:29 pm
by 89D/OSpree
the above statement is not mostly wrong. i am A.S.E. certified mechanic. been doin this s*** for years. ask any wrench turner and they will tell you the same. i even have many tech books that say the same. so unless 2 and 4 strokes are different in your part of the world. you should relly do some research.
Posted: Wed Aug 20, 2008 9:00 pm
by 89D/OSpree
on a 2 stroke motor the exhaust smells different because the oil is mixed with the fuel before it gets into the combustion chamber. therefore, it's burning the fuel and the oil. on the four stroke, it is not mixed with the fuel therefore it's not burned like it is on a 2 stroke. so, try smelling the exhaust from a moped then smell the exhaust from a car. big difference and the above said is why
Posted: Wed Aug 20, 2008 9:05 pm
by 89D/OSpree
now as for what kenny mccormick said about my statement being wrong, maybe he misread it beacause not all sprees are 2 stroke. i have a friend who has a 4 stroke spree. however, it wasn't bought from the factory that way. the engine was swapped to a 4 stroke. my spree has a dio motor in it. it didn't come from the factory that way.
Posted: Wed Aug 20, 2008 9:44 pm
by Clivester
89D/OSpree wrote:well firstly, all the 50cc sprees came out stock 2 stroke. if the motor was swapped out, here is how you can tell if it's a 2 or 4 stroke.
I have no problems with what you said - you qualified it first by saying Sprees are 2 stroke from factory.
EXCEPT FOR ONE THING
Many 4 strokes are air-cooled (like the chinese GY6s) and don't have radiators. I'll bet putting a 50cc GY6 type engine in a Spree would be quite do-able, though I don't know why you would want to.
I'd give you an A- !!!!!!!!!!!!!!!!!
Clive.
Posted: Wed Aug 20, 2008 10:10 pm
by Kenny_McCormic
89D/OSpree wrote: mixing oil with gas whether you pre-mix or the engine does it for you is a 2 stroke.a noob could easily be confused by this statemnt put 4 stroke oil in his hondas injector and blow the motor
4 stokes also have radiators, 2 strokes usually don't unless it was modified (usually stroker bores). There are just as many air cooled 4 strokes as there are water cooled this is the statement that sucks the most, very few 50cc mopeds (if any) are water cooled.
another way to be sure is the sound. if it sounds like most mopeds than it
probably is a 2 stoke. a 4 stroke sounds more like a street bike. Sound signature has to do with the muffler/exhuast system mostly.
And then there is the smell of the exhaust. 2 strokes smell like weed whackers, chainsaws, dirt bikes. 4 strokes don't. That completely depends on the oil
For the record, the fastest way to tell is exhaust port location, if its poking out the side of the jug its a 2 stroke, 4 stroke comes off the head or very close to the head(side valve).
Posted: Thu Aug 21, 2008 4:52 am
by maddog
is this dumb * week on this forum

dum * week
Posted: Fri Aug 22, 2008 10:38 pm
by nq50KillingSpree
apperantly i opened up a can of worms.....but i get the idea......its a 2 stroke.....thnx.......
Posted: Fri Aug 22, 2008 11:27 pm
by 89D/OSpree
no prob
Posted: Fri Aug 22, 2008 11:29 pm
by burnt_toast
I can't believe this was posted in Performance Tech..
Posted: Fri Aug 22, 2008 11:37 pm
by Kenny_McCormic
burnt_toast wrote:I can't believe this was posted in Performance Tech..
The 2 stroke will always outrun the 4 because the 4 only makes power every other revolution, 2 stroke makes power every revolution automatically doubling potential.