WFO Speedracer
A lifetime ban is like a lifetime warranty !
- Location
- Alabama
I wouldn't do it ,I heard after you hit 88mph all manner of hell breaks loose,you could mess up the whole space time continuum doing crap like that! :bigeyes:
12.000 RPM, 250HP, SXR hull
- Thread starter matejzivic
- Start date
I wouldn't do it ,I heard after you hit 88mph all manner of hell breaks loose,you could mess up the whole space time continuum doing crap like that! :bigeyes:
Zeon
WNY Crew
- Location
- Buffalo, NY/ Crystal beach, Ontario
1) this could be a realistic build. Ive played with alot of different toys and whatever else and if theres a will theres a way. ive made some pretty frankenstien like contraptions myself.
2) IDK where you plan to get 250HP from cuz i know they dont have that power. if you plan to have that power after turbo ... ive done plenty of turbo set ups... I DOUBT very much you will have room for this on top of trying to fit that MASSIVE motor in the jetski. I KNOW FOR A FACT (sat a 900rr motor in a js550) you would have to do some SERIOUS HOOD work and it would be super heavy/ top heavy
3) if you were to do this you would NOT use a prop from a superjet. you would have to use something that was bigger. if you have power you dont need a dinky pump. Just pull a prop off a scarab youll be good :Banane09:
4) good luck when you get any water in a motor with SUPER SUPER high compression.. i think its like 14:1 or somthing stupid like that.
5) if people wouldent look past frankenstien projects maybe some people would look into snowmobile motors with auto torque converters for that extra top end
if a ski had gears it would still matter... the prop would not spin the same speed with each gear. think about it. just like a car. gear ratios.... 5th gear would be significantly faster then 1st gear.
If the motor was in the bike and your at 12k in first your doing say 60. if your doing 12k in 5th gear your doing say 160. Now think about how much faster the wheels are spinning in 5th doing 160 rather then in 1st doing 60. either way your at 12000rpm. so the output change would be dramatic.
thank you guys for you helping me find some answers about this project.
I did not know that RPM-s of pump are "limited" to cca 8k RPM-s.
I had in mind to cut away the tranmision block from engine, so engine will not be so heavy. Don't worry how I will do this, I have whole bunch of machinery to work with metal. The only problem is time and that I do not know what is most important on driveline from impeler to pump and caviation...
The cooling of exaust will not be a big problem, because my friend works in AKRAPOVIC company if you heard for it, and he already done some similar projects for speed boats, he also instal turbo on Kawasaki ZX10R engine. Bike had 260HP on wheel, I was there when they measured in test chamber.:scared:
The turbo will increase the torque from bottom, so maybe I wil not need to spinn engine to 12.000RPM-s.
What are max RPM-s on sit down jet skis with 4-stroke engine?
Maybe I shoud use this bigger pump from sitdown 4-stroke jet ski.
That I like SXR hull is one thing and the other is that Eric Malone on EME1000 use SXR botton hull and yamaha top hull.
I realy don't know what is best to use, but If they do it.....
I did not know that RPM-s of pump are "limited" to cca 8k RPM-s.
I had in mind to cut away the tranmision block from engine, so engine will not be so heavy. Don't worry how I will do this, I have whole bunch of machinery to work with metal. The only problem is time and that I do not know what is most important on driveline from impeler to pump and caviation...
The cooling of exaust will not be a big problem, because my friend works in AKRAPOVIC company if you heard for it, and he already done some similar projects for speed boats, he also instal turbo on Kawasaki ZX10R engine. Bike had 260HP on wheel, I was there when they measured in test chamber.:scared:
The turbo will increase the torque from bottom, so maybe I wil not need to spinn engine to 12.000RPM-s.
What are max RPM-s on sit down jet skis with 4-stroke engine?
Maybe I shoud use this bigger pump from sitdown 4-stroke jet ski.
That I like SXR hull is one thing and the other is that Eric Malone on EME1000 use SXR botton hull and yamaha top hull.
I realy don't know what is best to use, but If they do it.....
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WFO Speedracer
A lifetime ban is like a lifetime warranty !
- Location
- Alabama
Here is my take on it,I would start with something like a Kawi Concours engine,lower rpm motor more torque,less peaky and shaft drive.
- Location
- So. IL
If you have the machinery just make a high horsepower SXR motor. A TON less design problems. But if you are persistent on having a huge boat anchor motor then you need to rely on a gear reduction just the like big 4 cylinder couches have in them. They reduce the 12K rpm's to a useable 8K.
But even if you end up with 250 HP SXR the extra weight would make the power to weight ratio less than a limited 800 in a light weight hull.
Plus the $$ for the 4 cylinder motor and machining would be more than a 50 pound trinity hull.
Run the numbers of weight vs power and you would soon realize that that HUGE motor would be a waste of time. Unless your main objective is to have a heavy unstable SXR.
But even if you end up with 250 HP SXR the extra weight would make the power to weight ratio less than a limited 800 in a light weight hull.
Plus the $$ for the 4 cylinder motor and machining would be more than a 50 pound trinity hull.
Run the numbers of weight vs power and you would soon realize that that HUGE motor would be a waste of time. Unless your main objective is to have a heavy unstable SXR.
- Location
- St.Louis Missouri
Good post. Instead of bashing him for looking outside the box you actually gave him some good advice.
I know his thread topic has been hit pretty many times and nobody has ever really completed this..but I at least give him props for not just doing what everybody else has done. Even if he cant complete the project, he will learn alot while doing it..and that in itself is worth it.
Thank you guys very much for patience.
Sometimes is better solve some problems on paper than in real life.
You give me a lot usefull infos, thats why are forum for, to talk about somebodies problem, yes?
Sometimes is better solve some problems on paper than in real life.
You give me a lot usefull infos, thats why are forum for, to talk about somebodies problem, yes?
WaveDemon
Not Dead - Notable Member
- Location
- Hell, Florida
your thinking is wrong. if you're in an overdriven gear your prop turns slower than the motor. just like the yamaha gear reduction on the 4 stroke sit downs.
in first gear you'll be turning the prop more than twice as fast (maybe 4x with a granny gear) as the engine rpm.
- Location
- Brooklyn NY
you want 200 plusssss power go to http://www.waterdawgkustomz.com/1200.php
its all set up you never make it with motorcycle engine you will be fix it all day long
its all set up you never make it with motorcycle engine you will be fix it all day long
SXR-FOREVER
Finally Flippin
- Location
- Lake Minnetonka, MN
holy old thread
the WaTeRhAwK
fryin' up a/m electrics..
- Location
- okc
you might try grafting a wetbike pump into your sxr hull, they are about the same circumference as a bowling ball.
WFO Speedracer
A lifetime ban is like a lifetime warranty !
- Location
- Alabama
All that is old becomes new again my friend.
global warmer
big time gas pumper
- Location
- on the beach
dude listen to the sensible replies!power to weight ratio is maybe the best for results,albeit not the cheapest,but if you must spend your time in the workshop rather than on the water drop the 4stroke,at least in a standup,to complicated!weight,size,rev's,electric's etc etc!! maybe look into a 2stroke outboard,for rev range,choice,compact cheap,triple's,v4,v6,fuel injection,you'll have fun with the exhaust whatever you do!besides a kawasaki dealer i know has seen a prototype 4stroke sxr about 3 years ago,probly wont be long now!
wsuwrhr
Purveyor of the Biggest Brapp
- Location
- Alta Loma, working in Upland
Yamaha already MAKES a "motorcycle-based" 1000cc engine with no transmission for their boats.
I think this "project" need a v-drive or outdrive to be complete.
Brian
I think this "project" need a v-drive or outdrive to be complete.
Brian
- Location
- Jersey
or you could get 255 by dropping an rxp-x motor..... the rxp motor conversion has already been done by river rat racing in havasu...... it was built as an exhibition ski for brandon mcmillan
- Location
- Australia
The prop isn't spinning at 12k in 1st & 12k in 6th because it has a transmission. The countershaft may have a ratio of 1:1 with the primary drive shaft in 6th gear which would mean if the motor could be mounted sideways with the countershaft facing the midshaft & a coupler was attached to the countershaft, in 6th gear at engine rpm of 12k the prop would be spinning at 12 k.
In 1st gear (I don't know the ratio) the countershaft might only be spinning at 2 or 3k while the motor is at 12000 rpm.
I have a friend that has built an insaine supercharged ski & he had to have a lot of the pump system custom made to handle the huge volume of water that a prop wanted to push through at very high rpm. He tried just about every pump available & couldnt get one that would handle the job
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the WaTeRhAwK
fryin' up a/m electrics..
- Location
- okc
- Location
- Largo, Fl
the WaTeRhAwK
fryin' up a/m electrics..
- Location
- okc
what was the outcome?
ancake:
not sure about that. I don't remember if they were trying to run a gearbox or not.
there was another group that were also building 440 hull to accept a wetbike pump and three cylinder suzuki engine from something. to get the pump to fit, they had to take a sawzall and cut the whole bottom section off of another hull and graft it on the hull they were using, cut out a bunch of material a do glasswork. if I remember right, the guy said he got everything layed up wet with resin, sprayed the top of the pump with mold release and pressed it into cavity until the resin went off. they also had to weld a cut section of a 440 exit nozzel on to the end of the wetbike pump so they could install the turn nozzel. that thing was freaky looking.