Chris
New member
Hey guys , jus baught a 1990 kawi 440 . bored out to 517 , and shaved heads , How can i get a little more jam out of these , i can only get about 33 mph out of it , and it takes a bit to get there ? more hp ?
tbalz
New member
Get a set of 550 cylinders and bore them out. Pipe it, port it, new impeller, 550 carb. Check out pwctoday.com...lots of great stuff there. I have a 440 and a 550.
Chris
New member
Ohh ok , How fast with the 550 and the impeller ?
tbalz
New member
dontknow mph, but the 550 is faster than a 1994 Yamaha Superjet.
If you like the ride and handling of the 440/550 kawi, go get a Yamaha FX-1. Made only 2 years, 94 & 95 so they may be hard to find, but i bet they are cheap. It is the same 701 motor/carb as the 94+ SuperJet, but with alot less weight and a way better handlepole. They had a completely different drive that had a smaller diameter intake and outlet nozzle and a very aggressive, super-light alum impeller. They will smoke virtually all stand-ups prior to the current superjet and the new kawi, but don't have that smooth handling of the S/J. They are squirrely just like the 550's, and no, a 550 won't beat a 94 superjet as those were 700's, but a well tuned 550 will hang with a 650 superjet (93 and older) and will surely beat a kaw 650 (pigs). We had em all in our group, (we even had a Kawi one-lunger 300 or 330!) and there were some really fast 550's but they never lasted the whole day. Something always went south on em. I had my FX for 4-5 years and it was awesome. Only mods i did were a Riva extended grooy rideplate, I don't even remember what intake grate I put on (it was a two-bar with foils...maybe Jet Dynamics?) and USI Racing steering/handlebar set up, and I deleted the choke for a primer - better starting and no restriction in the carb. Oh yeah, two bilge pumps with foot switch and polished alum outlets.
All other stand-ups had that thing....you know, when you leave the surface of the water, even for a split second, when the machine hit the surface again, it was like throwing a banana into a free spinning blender...that awful bog that could throw you into the bars... the 650 Kawis were the worst....the FX-1's didn't have that bog...at all....ever. It was an absolute rocket and I was radar'd at 50mph once. I'm sure all the new ones don't have that bog either and are probably much, much faster.
We used to ride Lake Superior and chase the big freighters coming into harbor, and jump their enormous wakes... as long as you could hang on to that squirrelly thing screaming across the water, if you were on the FX, you got to the ship first and were airborne farthest and highest.
OK now this gets weird. I did a search to find a photo of one for you, and I found this: www.blowsion.com; look under watercraft products, there is a photo of the FX-1 but guess what....that very machine was MINE!!! I know because that yellow you see on there? I did that. Stock color for the F and the 1 were white and it said YAMAHA in pink, but I changed that to yellow too. And the X i did in purple but stock was white with purple texture..CRAP!!! You can see the USI handlebar too and the MN lic and the license letters Lettertech made for me... it's SO weird! Anyway, have fun...I SO miss my standup. I'll get one again someday but it will be the new S/J. smoooooooooth and quiet.
All other stand-ups had that thing....you know, when you leave the surface of the water, even for a split second, when the machine hit the surface again, it was like throwing a banana into a free spinning blender...that awful bog that could throw you into the bars... the 650 Kawis were the worst....the FX-1's didn't have that bog...at all....ever. It was an absolute rocket and I was radar'd at 50mph once. I'm sure all the new ones don't have that bog either and are probably much, much faster.
We used to ride Lake Superior and chase the big freighters coming into harbor, and jump their enormous wakes... as long as you could hang on to that squirrelly thing screaming across the water, if you were on the FX, you got to the ship first and were airborne farthest and highest.
OK now this gets weird. I did a search to find a photo of one for you, and I found this: www.blowsion.com; look under watercraft products, there is a photo of the FX-1 but guess what....that very machine was MINE!!! I know because that yellow you see on there? I did that. Stock color for the F and the 1 were white and it said YAMAHA in pink, but I changed that to yellow too. And the X i did in purple but stock was white with purple texture..CRAP!!! You can see the USI handlebar too and the MN lic and the license letters Lettertech made for me... it's SO weird! Anyway, have fun...I SO miss my standup. I'll get one again someday but it will be the new S/J. smoooooooooth and quiet.
2stroken
New member
I have had them all. 440, 550, 650, 750, 650SJ I have even ridden a 300. Friend had a 76 400. Your easiest task would to be fine a 91 or newer 550 engine, they were piston reeds. Your gonna be hard pressed to get the 550 kawi past 45 mph. If you can find a 650 engine there used to be some conversions to put them in the 550. Bull head is right I still have my 1995 fx1 I bought it new as a demo unit in 1998. Thing rocks. It has a factory pipe and jet dynamics is the stuff for the fx1. The thing is bulletproof, if you can find one snatch it up. I sold a 1994 and a 1995 a few years back for friends. If you really want one they are on ebay from time to time. I guess I could part with mine, but it will cost you a pretty penny as they are hard to find. Factory pipe has a half pipe for the 550, and I wasn't that impressed with the performance still. Used stuff can be cheap. PJS used to make custom cylinders and stuff for them, I think some even stroker cranks. In my opinion you would be better to try to stuff a 650 or 750 in it. The 92 750 had some crank issues. I think in 96 they went to the big pin crank. Bottom line find an fx1 I have mine and it is 10 years on the stock engine. I didn't ride it last year, as jetskiing buddies are hard to find, and we have relocated and our old house was on the lake. I have some yami parts to make them scream if you want. I have some 62T cases(dual carb bigger reed cages) I even have a able billet cylinder and head with bridged exhaust ports if you know anybody who wants to build a bad bad yammi. I was gonna build up one of my 650 sj's into a mod, but never had a chance. Who knows it might be something to build for my kids.
zigzag
New member
Lean fuel mixture a little but not too much just to where it gets snappy on acceleration out of the water from a stop. I have a 550 superjet it will do about 40mph all it has is a k-n air filter and intake weisco piston and rings mariner rideplate every thing else is stock.also a bilge pump helps to keep all water out of hull any water is friction on the drive shaft you wouldnt think it would be all that bad but you would be very suprised how much power is lost. keep it dry on the inside and it will fly.
2stroken
New member
zigzag said:
550 superjet?
40mph from a 550 kawi or even a 650 superjet with just a ride plate and a K&N is pretty optomistic. I would think a 550 with no engine mods is in the low 30's. Of course I guess if 34mph is almost 40mph then that could be true.
I have an FX1 that has been GPS'd at 52MPH, it is a dicey ride at that speed.