Great build.... I put a skidoo rotax 500 motor on a Baja Dune 150 frame.. and it is crazy fast!! but not so much off the gun... What is the gear ratio in your reduction box?? right now I'm running 4.7 to 1 ... which is closer to what they run in the formula 500 track races.(with my same engine) but I really want it to be more set for acceleration... so, if you could please help, . Whats the tooth count on your gears?? any help would be awesome. that way i'm not guessing. thanks.
So if what your saying is true, why does a snowmobile with a stock pipe, and NO silencer, make so much less horsepower then it would WITH the silencer? Vintage racers had the outlet on the pipes smaller for a reason, backpressure. They ran no silencers, and for that, made the outlets smaller.
1) Low-end operation, cams with significant overlap, backpressure, vs. none... Without the backpressure, the carbs would see a more pulsed signal - the airflow will have more fluctuation, and this screws up the carb's metering. This is true with ITB carbs like your Mikunis.
2) You need at least some backpressure to keep cooler air from rushing into the exhaust ports on the downstroke of the piston to keep the valves and seats from warping, that is why you never run an engine without a header or manifold connected. Mixture is also affected by backpressure.
Funny... As two strokes have ZERO cams or vavles. Secondly, two strokes are supposed to suck in air/fuel back through the exhaust port that's why they have expansion chambers. They create a pressure wave that forces air/fuel mix that escapes during the period in which the incoming charge is pushing out the spent mixture. The length of the stinger, or silencer effects power characteristics slightly at best.
first of all you fucking retard 2 cycle engines have no cams. and you are making yourself look like an asshole by trying to tell someone how to work a 2 stroke. and 2 cycle engines need no silencer. the only reason why they have them even from factories is because they are too loud and because they need a spark arrestor. i race an 86 atc250 r with an esr 330 kit making about 60 hp running 111 vp and fo expansion chamber. been running like that for 2 years and no problem.
not true dude you need expansion chambers to at least give some back pressure although you dumbfucks way above should know if your carb is jetted right and the air/fuel mix is set also, you will not fry your damn rings. don't talk unless you guys know.... oh ya and 2 strokes dont have fuckin cams. and valve wise the type of valves they have are reeds... =/
actuly this motor does not have reeds. its a rotary valve engine witch is a spinning metal disk that opens and closes the intake valves and it is run off the crank and shares a common shaft with the water pump. this type of engine is much more powerful then a reed valve engine of similar size and and much much more efficient if you want to turbo it.
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nitrosport5 1 year ago
Holy S .. Im in LOVE
71TDOG 1 year ago
Great build.... I put a skidoo rotax 500 motor on a Baja Dune 150 frame.. and it is crazy fast!! but not so much off the gun... What is the gear ratio in your reduction box?? right now I'm running 4.7 to 1 ... which is closer to what they run in the formula 500 track races.(with my same engine) but I really want it to be more set for acceleration... so, if you could please help, . Whats the tooth count on your gears?? any help would be awesome. that way i'm not guessing. thanks.
calholli 1 year ago
ya it might have 100hp orihinally to the crank but sounds boggy as hell!
GeaserakaErik 1 year ago
@GeaserakaErik maybe its a 2-stroke?
malibuaudio69 1 year ago
wow that fucker must fly my 95 formula 583 does 115 mph
dodgekickzass 2 years ago
check my cart out i built it this year in school JR. year
put a 540cc Yamaha snowmobile motor in it. sick full suspension in it to.
deanthemotocrossman 2 years ago
its called exhaust scavenging and its what "tuned pipes" are all about. kornball is DEAD ON
davidredhawk 2 years ago
Did you have to uprgrade the torque converter / drivetrain because of the extra power?
chillrasta12 3 years ago
anyone know where i could get an engine like this one and how hard it would be to put it in my fl350 odyssey
gh3mindfreak 3 years ago
How high can you get the RPMs? I would think that the stock ody pipe is holding the motor back.
sunblock1977 3 years ago
thats the 583 rotax exhaust that has been custom cut and rewelded to fit it in the frame.
gh3mindfreak 3 years ago
yes the 583 is rated between 95 and 105 hp.
drkvltprlsb18c1gsr 3 years ago
90 hp?
leviterande 3 years ago
rotax have a valve on the intake and some have a rave also you do not need a muffler
if jetted right.
lbethke 3 years ago
Rotax engines are sweet
Search loud rotax hillcimb to see a fucking awesome performance
flamerail 3 years ago
airs gonna get in pipe more easeyer and lean out and burn rings. buts not my problem. looks wild!
matt0107 4 years ago
So if what your saying is true, why does a snowmobile with a stock pipe, and NO silencer, make so much less horsepower then it would WITH the silencer? Vintage racers had the outlet on the pipes smaller for a reason, backpressure. They ran no silencers, and for that, made the outlets smaller.
Velislide 4 years ago 2
Your going to burn that engine up without a silencer on it, needs backpressure.
Velislide 4 years ago
only with 4 strokes
and then you just need to adjust the airfuel mixture
lcurtizz 4 years ago
Obviously you have no clue about what your even trying to say, so dont bother.
Theres a reason two strokes have expansion chambers and silencers, go look it up if you really want to know.
And yes, without a silencer, that engine is going to burn up, AND he will have about 10% less HP.
Velislide 4 years ago 2
no
you just need the expansion chambers
you have no idea what you are talking about.
look at vintage race sleds, they have no silencers, i have a txl and its never had a rebuild and its still making 73 horse.
lcurtizz 4 years ago
1) Low-end operation, cams with significant overlap, backpressure, vs. none... Without the backpressure, the carbs would see a more pulsed signal - the airflow will have more fluctuation, and this screws up the carb's metering. This is true with ITB carbs like your Mikunis.
Velislide 4 years ago
2) You need at least some backpressure to keep cooler air from rushing into the exhaust ports on the downstroke of the piston to keep the valves and seats from warping, that is why you never run an engine without a header or manifold connected. Mixture is also affected by backpressure.
Velislide 4 years ago
Funny... As two strokes have ZERO cams or vavles. Secondly, two strokes are supposed to suck in air/fuel back through the exhaust port that's why they have expansion chambers. They create a pressure wave that forces air/fuel mix that escapes during the period in which the incoming charge is pushing out the spent mixture. The length of the stinger, or silencer effects power characteristics slightly at best.
Kornball426 4 years ago
first of all you fucking retard 2 cycle engines have no cams. and you are making yourself look like an asshole by trying to tell someone how to work a 2 stroke. and 2 cycle engines need no silencer. the only reason why they have them even from factories is because they are too loud and because they need a spark arrestor. i race an 86 atc250 r with an esr 330 kit making about 60 hp running 111 vp and fo expansion chamber. been running like that for 2 years and no problem.
glamis19 3 years ago
not true dude you need expansion chambers to at least give some back pressure although you dumbfucks way above should know if your carb is jetted right and the air/fuel mix is set also, you will not fry your damn rings. don't talk unless you guys know.... oh ya and 2 strokes dont have fuckin cams. and valve wise the type of valves they have are reeds... =/
boboandsnakeingrass 3 years ago
actuly this motor does not have reeds. its a rotary valve engine witch is a spinning metal disk that opens and closes the intake valves and it is run off the crank and shares a common shaft with the water pump. this type of engine is much more powerful then a reed valve engine of similar size and and much much more efficient if you want to turbo it.
dryice0002006 2 years ago
Take the think for a spin. Sounds damn good.
fxdwings 4 years ago 2