Jet Ski Engine

[screamnfly]

Hello all!
My name's Justin, I'm fairly new to the karting world. I first had a small home made kart with a 5home Briggs on it. T. I went to school to fix jetskis, and my dad's best friend James builds shifter karts in Ocala Florida. So I have a GP800 engine in my shed out of a 2001 Yamaha GP800. It's a 2 cylinder 2 stroke with 84mm wiseco pistons, billet aluminum high compression head, big bore carbs with the chokes removed and filled in, after market flame arrestees similar to k&n, and carbon fiber reeds for immediate throttle response. I got this out of a blown up jet ski and want to put it on a kart. The ski would do about 62-65mph so I'm thinking with the right gearing it should scream. I work for a metal fab company and will build the frame, and laser out any brackets needed, motor mounts, etc. Then machine a solid axle with keyways for the brake rotor and driven gear instead of set screws. I can't find anyone who has done something like this so if anyone knows why or has tried let me know. The hard part is the cooling system because its not closed and sucks up lake water then meets the gasses in the exhaust manifold and stays with it out the pipe. But this engine has a big water box. So I'm going to put baffles in the pipe after the water box in a tube going straight up. And run a bilge pump to cycle the water out of the water box (or muffler) to a radiator with a fan, then back into the head again. There's more than enough power in the stator and wouldn't put a load on the motor. Any ideas are appreciated. Can't wait to learn from you guys. Later.

 

[BirdFanatic]

if you say it does 62-65 mph in water this thing should do 130 140 mph on land water is harder to move through

 

[itsid]

!!!!

Don't.. please don't!!

if it's the engine I think it is, we talk about 120hp @ 7000rpm here
on a kart that can be read as "instant death"

with that amount of power you can gear into 150mph which would be... uhm let's say dangerous

even a 4:1 ratio on huge wheels (22") would end up close to 115 mph

and a more reasonable top speed gearing (8:1) with ~60mph
will produce an amount of torque that will get you into troubles really easily.

get at least a full caged kart if you insist, but get a professionally build one,
one minor flaw on the chassis and you end up with a steel pretzel which you do not want to be inside of.

'sid

 

[Poboy kartman]

I'm going to quote a couple of other members here. .....they may reconize their posts......and understand them...whether anyone else does is of little matter to me anyway.......

"WOW....just wow".........."well...........bye."

 

[BirdFanatic]

So your saying full caged like mine right mine was made by a company called made for you products located in pinion hill California (mine has enough room for an engine twice the size of the 390 i have now) not saying im crazy enough to do it but it would be a fun project

!!!!

Don't.. please don't!!

if it's the engine I think it is, we talk about 120hp @ 7000rpm here
on a kart that can be read as "instant death"

with that amount of power you can gear into 150mph which would be... uhm let's say dangerous

even a 4:1 ratio on huge wheels (22") would end up close to 115 mph

and a more reasonable top speed gearing (8:1) with ~60mph
will produce an amount of torque that will get you into troubles really easily.

get at least a full caged kart if you insist, but get a professionally build one,
one minor flaw on the chassis and you end up with a steel pretzel which you do not want to be inside of.

'sid

 

[OzFab]

I don't think he means that much cage, just a buggy with a decent frame & cage as opposed to a flat frame kart...

 

[BirdFanatic]

true so your saying my frame can handle it

I don't think he means that much cage, just a buggy with a decent frame & cage as opposed to a flat frame kart...

 

[itsid]

since made 4 you products in pinion hills makes plastic parts (clamps for wires and hoses)
I'd say it's either not sturdy enough for such engine or not the maker of your frame

'sid

 

[BirdFanatic]

i want to call and find out if they have ever built chassis
just because im interested in the history on this kart

 

[fourtogo]

!!!!

Don't.. please don't!!

if it's the engine I think it is, we talk about 120hp @ 7000rpm here
on a kart that can be read as "instant death"

with that amount of power you can gear into 150mph which would be... uhm let's say dangerous

even a 4:1 ratio on huge wheels (22") would end up close to 115 mph

and a more reasonable top speed gearing (8:1) with ~60mph
will produce an amount of torque that will get you into troubles really easily.

get at least a full caged kart if you insist, but get a professionally build one,
one minor flaw on the chassis and you end up with a steel pretzel which you do not want to be inside of.

'sid

Sid what do you think will get you in more trouble . A larger engine or you lack of self control of your right foot. It's kind of like owning a Lambo<< oh wow this thing can go 220 but I never drive that fast . I thought Germans were uoober horse power guys ?

 

[ML-TOYS]

How about this thread stays away from your kart and sticks with the original post.

That being said Omg ! That is a crazy engine to put on a kart.

So your saying full caged like mine right mine was made by a company called made for you products located in pinion hill California (mine has enough room for an engine twice the size of the 390 i have now) not saying im crazy enough to do it but it would be a fun project

true so your saying my frame can handle it

i want to call and find out if they have ever built chassis
just because im interested in the history on this kart

 

[Poboy kartman]

!!!!

Don't.. please don't!!

'sid

How did you know what I was thinking about posting?????

 

[screamnfly]

I've seen guys with gsxr1000 engines on YouTube, cbr900, I can control my foot, like he said about the lambo you don't have to use it. I don't think that with just one single gear it can span from 0-130, if it did either it would have **** from the take off or be weak at the top n full of torque, that's kinda what I'm wanting. Gear it so it just spins out if I punch it. Yes the jet ski will do 60 but it's also in about 2" of water with extremely low friction at full plane. It will be fast but I can control it. I work for a company that makes sprockets so I'll be calculating and trying any gear ratio I want. So I plan on spending a lot of time dialing it in. I'm not using a shifter and considering using it in a buggy or making two bodies and put the motor on a plate I can transfer from the buggy to the cart just by taking off the throttle cables. Have everything tight together. I have a 200mph crotch rocket but I don't ever go that fast and don't plan on it, I tried 150 one time for about 10 seconds and that's as far as I need to go, I'm not making the kart to do that, the bike does it, I just want it to be super torquie

 

[screamnfly]

I'm more worried with a buggy that the stance and suspension will make it flip easy, if I can keep it low and flat and wider than normal it will force it to spin out instead. I'm not posting this to ask about chassis really, more or less if anyone has heard about water cooling an engine that uses water but isn't a closed cooling system.

 

[screamnfly]

The other thing about this engine is it has a nice smooth easy to control powerband. You can jump straight in it but if you go easy you can control it well.

 

[screamnfly]

Although, my biggest consideration chassis wise is deciding if I should make it street legal, since there aren't may places around her I can open this thing up, that would make it bigger heavier, safer, still open though, and calm it down a little but I'm not sure what our requirements are

 

[ML-TOYS]

Stop making a seperate post for every thought. Use the edit button rather than reply to your own post.
Thank you

 

[firemanjim]

please use the EDIT button in the lower right corner of your posts to add to them, instead of multiple posts only a minute or 2 apart.....

 

[itsid]

Sid what do you think will get you in more trouble . A larger engine or you lack of self control of your right foot. It's kind of like owning a Lambo<< oh wow this thing can go 220 but I never drive that fast . I thought Germans were uoober horse power guys ?

Well I do not think it's like owning a Lambo..
it's nowhere near comparable if you ask me!

Let's try to get a car perspective shall we...

it's like owning a Brutus... oh you don't know Brutus I assume:
http://www.youtube.com/watch?v=wJn7LHE83cc

while it is possible to get it going and still stay safe.. you can go faster and quicker in a much safer way with a much smaller engine (say for example a Lamborghini )

take the 32hp gx390 mini stock engine for example that is in BirdFanatics mini stock car..
that on a kart like his can be quite a blast.. and since everything is in proportion it can be considered "safe fun".. go full throttle no problem.

A 120hp two stroke
-which if you ask me is much more violent than a 120hp four stroke like a mildly throttled cbr900 for example-
is something completely different.. the kart that should be build around that ..

let's keep a car comparision shalll we;
and let's be gentle and take 1968 safety standards (not todays)
so what you'd need to build would be equally well made and safe as a 1969 911 Porsche (110hp @6500 rpm)

if you can do that... go ahead!
if not.. go away!

Yes GiXXer Karts (99.5% power 0.5% control...) to me the guys that chop racekarts into gixxers are insane in a bad way.. that is pointless useless and still a better idea than to use a 120hp two stroke
oh btw I'd make a bet and nearly every GiXXer could be beaten on the tack with a standard race compliant 250cc shifter kart!

let me quote Pirelli: "Power is NOTHING without control!"

I repeat: please don't.
if you insist: please stay safe!

Just keep in mind: testosterone gives bad advice

'sid

 

[OzFab]

Ah, Brutus, the brainchild of the devil himself, built by "a madman"