Dayum these are BLINGIN!

as i recall, when i put the 2 manifolds back to back, the riva manifold has wider openings, than the kawi manifold, where it meets the adaptor plate.

if you were to try to widen the kawi manifold to the width of the riva, you would grind right through it.

the bolt patterns are the same, but thats about it.

.....as i recall.


So as DBR stated.....that riva is nothing but a kawi 650 manifold.....

That statement isn't true eh?
 

waterfreak

I had a vision!
Site Supporter
Vendor Account
Location
s florida
personnally, I love that set up. Simple, dependable, reliable and powerfull. Combined with a single Novi 48mm carb, that thing will hit like brick wall. I know that the Russians are using that same set up in all their boats and they all hit extremely hard.

Proper jetting and set up is the key. I'm also running the same set up on my 5mm able motor and it rippps!
 

Mike W

Infidel
Location
North Florida
I went with the riva single intake and a single 46 and like it. I also run an unported 62T/61X though. I also never run WOT for more than a second or two so I don't think I will ever run into any issues with it.
 
personnally, I love that set up. Simple, dependable, reliable and powerfull. Combined with a single Novi 48mm carb, that thing will hit like brick wall. I know that the Russians are using that same set up in all their boats and they all hit extremely hard.

Proper jetting and set up is the key. I'm also running the same set up on my 5mm able motor and it rippps!

Hey! A real world experience! This is what I'm talkin' about! ..and with my favorite buzzwords!! Simple, Dependable, Reliable, and Powerful!:woot:
 

YAMA CAT

Catnip Junkie!
Location
B'ham, AL
Oh, and Barb, I had two boats to put together. They were both stripped to the hull. As I said, the white one is done except for figuring out an electrical issue. This ebox is the same one out of my old square, and it did the same thing near the end of last season. All I should have to do is swap the coil or cdi......one or the other.

Same old excuses ..... blah blah blah..... It doesn't take that long to pull a motor and swap.
 
So as DBR stated.....that riva is nothing but a kawi 650 manifold.....

That statement isn't true eh?

that statement is not true. theyre very very similar, but the riva holes are more elongated than a kawi's.

you decide....

the kawi aftermarket 650 manifolds have ports that look like this stocker:

bx201fe.jpg




the riva manifolds have ports that resemble yamaha oem stockers:

attachment.php




if you were to try to widen a kawi manifold to match the flow capacity of an oem yamaha manifold, youd grind right through it.

thats why riva made their own, based on the kawi 650, but with wider ports and a throttle cable bracket.
 

GIL

Power In The Hands Of Few
Location
Cullman AL
personnally, I love that set up. Simple, dependable, reliable and powerfull. Combined with a single Novi 48mm carb, that thing will hit like brick wall. I know that the Russians are using that same set up in all their boats and they all hit extremely hard.

Proper jetting and set up is the key. I'm also running the same set up on my 5mm able motor and it rippps!

just my 2 cents-if Steve says it's good-I'd do what he says-if I recall, he does this for a living and a hobby and is a very respectable guy/builder in the freestyle world.
 

THRUST

ThrustInnovations.com
this set up is based on real world experience and years of and thousands upon thousands of dolars into testing a very reliable but yet powerful engine package . we have tried and tested back to back everypart on the market . sure going with duals will give you some more power but also at a price . bottom snap , more water ingestion, harder to tune for inexperienced tuner , more cost . in this case he was coming from a small engine and it is best to build up in steps . Get used to this power get good and then buy one more novi and a dual manifold and you got more power again . if everybody needed all the power available why not just build a 12mm with 91 mm pistons then . or buy an eme 1000 which probably only 10 people in the world could actually ride to its potential . just an opinion though and everyone has a right to them .
 
So why make it fit a Kawi engine then?

i dunno. but what does it hurt?

perhaps one day, someone at riva (maybe tim judge) probably took a 650 manifold, held it up against a set of 62t cases and said, "i can make this work efficiently with some tweaking and an adaptor plate", and kept the 650 bolt pattern, but changed other things. :dunno:
 

Big Kahuna

Administrator
Location
Tuscaloosa, AL
I ran that intake setup you got there (with a 48 Full Spectrum) on a ported 760 last year. The carb was jetted right, but wide open runs longer than 5-8 seconds were a no-no. You could feel the RPM start to drop after that.
The cylinder had some nice scoring at the end of the season.


When I recommended a "real manifold", I did so because I wish I had.

I have not run the ATP, but contact njfl. He's running one on a big ADA stroker.
Also, ask Supertune.

IMHO, you're making a mistake running that manifold.

I know you did not post that............ after all the discussions over the years where you said that you could run a ski WOT with the single with no problems!!!!!!!!!!

:smashfreakB: :crutches: :nutkick:
 

Matt_E

steals hub caps from cars
Site Supporter
Location
at peace
I know you did not post that............ after all the discussions over the years where you said that you could run a ski WOT with the single with no problems!!!!!!!!!!

:smashfreakB: :crutches: :nutkick:

"Over the years"? Puleeze.
I ran it for one summer. Yes, it seemed to run fine on WOT runs. But after about 10 seconds (right about the max that I'd run WOT) he RPM would slowly slowly start to drop.

I had no qualms about doing so until the latter half of the season, when I started getting suspicious.
And then I found some light scoring at the end of the season.
I know the carb was jetted right. Was the singe to blame? Was there even a problem?
I don't know, but I wouldn't do it again.

Also, I ran a Frankenstein with identical 48 Single at the same time.
It runs fine, WOT for longer than 10 secs. But it has a stock rev limiter.

There, you heard me say it.
The more I stick around, the more I learn how little I know.
 
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Big Kahuna

Administrator
Location
Tuscaloosa, AL
uh, guys, there is a difference from a Kawi OEM 650 manifold and say a Westcoast or BCW 650 manifold that is ment to utilize a 44mm carb. I ran one of Rick Roy's old single setups that used the ADA Adapters and a BCW/Westcoast (cannot remember which mani-sold it to skinnyman) and it was opened up at the throat for a bottom bored 44 to match 48mm and ported. It worked great until you wanted to cruise up the lake. No fun doing that, like a light switch.
 

Big Kahuna

Administrator
Location
Tuscaloosa, AL
"Over the years"? Puleeze.
I ran it for one summer. Yes, it seemed to run fine on WOT runs. But after about 10 seconds (right about the max that I'd run WOT).

I had no qualms about doing so until the latter half of the season, when I started getting suspicious. The RPM would slowly slowly start to drop.
And then I found some light scoring at the end of the season.
I know the carb was jetted right. Was the singe to blame? Was there even a problem?
I don't know, but I wouldn't do it again.

Also, I ran a Frankenstein with identical 48 Single at the same time.
It runs fine, WOT for longer than 10 secs. But it has a stock rev limiter.

There, you heard me say it.
The more I stick around, the more I learn how little I know.

That was the same issues I found, you could feel it start to lean out and loose power. I still liked the setup as well. But I had the TLR modded carb and it changed with the humidity and temp, if it went form warm and sunny to cooler and cloudy or vice versa or if a rain shower blew through I had to tweak on it!!!!!!:spank:
 
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