Need More Power

Rompn

Rompn

Location
La Crescenta, CA
Sounds like you need a 550 reed engine at minimum, yes it fits right in what you have. Depending on how big you really are, you may consider jumping up in ski size to something like a 650 or 750. Plenty of power and a much wider and longer hull on both.
 
kwakhead

kwakhead

Location
macomb
you definetly need a bigger engine. dont waste ur time with a 400cc engine, that was the very first model kawasaki made, the js400. and its a slug. drop in a 550 piston port or a 550 reed motor, though a reed motor will cost substantially more than a 550 piston port. BUT, if your going to build up ur engine, DONT BUY A SKAT 15 degree prop, the stock prop is actually around 16.5 degree straight pitch, and when u build the engine, it makes no sense to bring the pitch down, because you will loose power. THE MORE POWER UR ENGINE HAS = THE HIGHER PITCH PROP U NEED (typically) u can always do something else and tune it how u want, but im expeirienced with these skis and id say if u build ur engine, keep the stock 550 prop. IF YOU DROP IN A 650 OR 750 MOTOR ID RECCOMEND PUTTING A 650 PUMP IN, OR U CAN USE A 20 DEGREE SKAT OR SOLAS PROP WITH THE STOCK 550 PUMP, whatever u do, ur gonna need a different pump and driveline, or u will screw up ur bulkhead, read more on this in the next paragraph.
AND if u put a bigger engine in there, you will need a 550 pump and a 550 driveshaft, (the 440 and 400 pumps put all the pressure on the bulkhead and put alot of stress on it, and with alot of power u can rip the driveshaft out of the bulkhead!!!) when u pass 35 hp, u want either a 440 bulkhead support bracket, or a 550 pump and driveline, period.
stock 400 motor 23hp or so
stock 440 motor with bn38 carb 27hp
stock 550 motor with bn38 carb 32 hp
stock 550 motor with bn44 carb 35 hp
stock 550 reed motor with bn44 carb 41hp and better throttle response, reliability, and bottom end
stock 650 motor with the 28mm keihin junk carb 51hp
stock 750 small pin single carb 62hp or so
stock 750 big pin dual 38mm keihin carbs like 75hp

whatever u do, its gonna take some money, different engine, and some work to move that thing past 40mph and what u need hp wise is at least 50hp

my old 550 had every mod done, everything, pump, engine, gas tank, hsndle pole, all the mods for everything, over $2000 invested, pulled hard, killed all the stock 800sxrs, had maybe 81hp. but, i blew the engine and rebuilt it every year, eventually got smart and just threw in a 750 bored to 780, and modded that so i can have more reliable power and faster speed. i also put in a 650 pump. if u want the details, check my build thread, ive done many builds before, but this is the first ive ever posted
 
kwakhead

kwakhead

Location
macomb
Quinc said:
Port the piss out of it. Step up to dual carbs or single 44, blue print your pump, add a pipe, high comp head, new prop, lighten the fly wheel, advance the timing, etc etc etc
http://www.groupk.com/k440.htm
Click to expand...

no effense man, but im sure we both know how much money he will waste trying to get it to go fast. U could bore it out to 550cc's, u would need to buy 550 sleeves and re sleeve it, but there ya go, and do everything else i said to do with the pump, if u gonna go past 40hp, u need the 550 pump and driveline, the 440 driveline will crack and break the bulkhead from the pressure
 
Quinc

Quinc

Buy a Superjet
Location
California
kwakhead said:
no effense man, but im sure we both know how much money he will waste trying to get it to go fast. U could bore it out to 550cc's, u would need to buy 550 sleeves and re sleeve it, but there ya go, and do everything else i said to do with the pump, if u gonna go past 40hp, u need the 550 pump and driveline, the 440 driveline will crack and break the bulkhead from the pressure
Click to expand...

Port the piss not bore the piss out of it. :) There is another thread on here somewhere the guy was getting high 40's out of his 440.
 
Kohldanielzimmer

Kohldanielzimmer

Sierra Nevada Runoff Rider
Site Supporter
Location
Ahwahnee, CA
kwakhead said:
DONT BUY A SKAT 15 degree prop, the stock prop is actually around 16.5 degree straight pitch, and when u build the engine, it makes no sense to bring the pitch down, because you will loose power. THE MORE POWER UR ENGINE HAS = THE HIGHER PITCH PROP U NEED (typically) u can always do something else and tune it how u want, but im expeirienced with these skis and id say if u build ur engine, keep the stock 550 prop.
Click to expand...

I respectfully disagree for several reasons. 1) this gentleman indicated that he was quite large and wanted lower end power to pull him up and 2) a skat 15 is much better than the thick aluminum oem impeller.

However,I was hypothesizing about a 550 driveline with the 15* impeller. So with that said, a 16* skat with a 440/400 driveline, as you have in your machine, would probably be more appropriate.

Good luck and try not to spend too much money on your first ski. Sooner or later you will likely want to upgrade again.
 
kwakhead

kwakhead

Location
macomb
Kohldanielzimmer said:
I respectfully disagree for several reasons. 1) this gentleman indicated that he was quite large and wanted lower end power to pull him up and 2) a skat 15 is much better than the thick aluminum oem impeller.

However,I was hypothesizing about a 550 driveline with the 15* impeller. So with that said, a 16* skat with a 440/400 driveline, as you have in your machine, would probably be more appropriate.

Good luck and try not to spend too much money on your first ski. Sooner or later you will likely want to upgrade again.
Click to expand...
yeh ik what ur saying, but i was talking about getting a higher pitch if he wants to start beefing up his engine, or even getting a different engine, and i know what the other guy is talking about when he said port the piss out of it BUT LETS NOT FORGET, THIS IS A JS400 NOT A JS440, ITS THE VERY FIRST AND SLOWEST SKI KAWASAKI EVER MADE, AND HES A BIG GUY, ID AGREE WITH EVERYBODY ELSE THAT HE NEEDS A 550 MOTOR AT LEAST, AND BUILD IT UP, AND IF HE WANTS THE 550 OR BIGGER MOTOR, HE NEEDS AT LEAST A 550 PUMP AND DRIVELINE, BECUASE THE OL JS440 JS400 DRIVELINE WERE BUILT TO PUT ALL THE PRESSURE ON THE BULKHEAD AND THATS A BAD THING!
 
kwakhead

kwakhead

Location
macomb
DUDE, IN ALL REALITY, sorry to say, but ur gonna spend at least $500 getting this thing to go the way u will need it to, just sell it and buy a js550 any year after 85, or a 550sx, id actually stray away from the 650sx, its very stable, but its a SLUG! its a 650 motor that came with a 28mm carb lol, who puts a bn38mm carb on a js440 then goes and puts a 28mm carb on a 650sx? doesnt make sense, but thats how they came stock. go for a 750sx or superjet if u have the money, but i think above all, what ur looking for is a 550sx, 1: its an on budget ski lol, 2: its more stable 3: it has cool hydro turf IMO 4: it carves better and grips better than the js550 and it has a stronger hull the the js550, it was more powerful than the 550, better throttle response due to the bigger carb and reeds and smaller and lighter driveshaft it came with, and if u can find one with the flame graphics they came with, lol thats a bonus cause i love those graphics lol
 
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