gp800 66e motor???

[superramjet]

at one time Riva had a single pipe for the 66e motor. Heard it was hard on pistons, I saw a picture once but never found one. Somebody's got to know where one is or the stampings might still be around.

 

[Freestyleriverrat]

I am sure Jeff can find a more efficient way to make his pipes if the demand is there.

 

[blaster800]

A cheaper route is the groupK Sleeper package. Sounds promising b/c it is designed to give good increases in power from low to mid rpms. That mod is only 450.....pretty much standard porting price and the cylinder gets a fresh bore and hone. At minimum if you do porting for low end power, the pipe, carbs and say a conservative 170-180lbs compression it should be rockin. pretty hard and pumping out at least 160hp :bigeyes: That is just from my guesstomometer :haha:

the sleeper package does not get a bore ! just porting and compression mod with adjustment to correct squish area !

 

[Freestyleriverrat]

the sleeper package does not get a bore ! just porting and compression mod with adjustment to correct squish area !

My bad.....the groupK BB kit is bored but the sleeper is mainly just porting and a head mod. I agree with superramjet. If you go gp800 do a big bore or it might not be worth the effort.

 

[Freestyleriverrat]

Got my gp800 motor today. Here are some more pics. That crank is huge :bigeyes: But surprisingly the motor is not that heavy. Achually feel pretty light.

 

[Freestyleriverrat]

couple more. I'll post some comparison photos of the 800 crank and a 701 crank later for comparison.

 

[blaster800]

And if you big bore it, you put regular sleeves in, or if you get it ported you have to get it replated.

just a note : when group-k does the sleeper porting they do NOT recoat the cyls . and have had good success with that method

 

[Mile9c1]

I don't see why you'd have to replate it if you port it, you're not porting what the pistons ride on (you're taking material off). I think Harry mentions that you have to use special porting tools, because the nicasil can chip where you don't want it to.

 

[blaster800]

I don't see why you'd have to replate it if you port it, you're not porting what the pistons ride on (you're taking material off). I think Harry mentions that you have to use special porting tools, because the nicasil can chip where you don't want it to.

YUP!:arms:

 

[Freestyleriverrat]

I weighed the longblock of my old kawi 650 motor and the 66e. The kawi longblock was 52lbs w/ bedplate attached and the 66e was 62lbs. So almost exactly 10lbs heavier on the long block. The 701 longblock should be heavier (larger crank) than the kawi so the difference should be less between the 701 and 66e

 

[Freestyleriverrat]

This is just my observation. Nothing is to scale, it is just a representation

 

[SuperJETT]

I weighed the longblock of my old kawi 650 motor and the 66e. The kawi longblock was 52lbs w/ bedplate attached and the 66e was 62lbs. So almost exactly 10lbs heavier on the long block. The 701 longblock should be heavier (larger crank) than the kawi so the difference should be less between the 701 and 66e

I wouldn't say that about the crank, since a Kaw 650 has a longer stroke than a 701---70mm vs 68mm.

 

[Freestyleriverrat]

I wouldn't say that about the crank, since a Kaw 650 has a longer stroke than a 701---70mm vs 68mm.

I am just talking mass, the 701 looks larger irrespective of stroke.

 

[Freestyleriverrat]

Darin, did you find the stroke on the 66e? or does someone know?

 

[Matt_E]

Should be 78mm.

 

[Freestyleriverrat]

Should be 78mm.

Nice :woot: Just from looking at the motor it has allot of cool features like the curved transfer ports, cases look like at set of ported 62t, larger transfer ports, PV's from the factory, the beefy crank, individual cylinders that flow well all the way around. It is just a cool motor. 120hp stock w/ a restrictive exhaust ect...

 

[Mile9c1]

The Kawi 650 motor is probably the same weight or more than the 701. A 750 is heavier than a 701, I'm pretty sure. They're close though.

I weighed a 62T and a 66E longblock earlier this year and the 66E was about 15 pounds heavier. Most that is in the crank.

 

[Exile]

78x82 if im correct...but i wonder how advanced the transfer porting is on the 800 engine compared to a lamey....and is the yamaha powervalve just as good or better than a sea doo rave valves....just curious!?

 

[Freestyleriverrat]

78x82 if im correct...but i wonder how advanced the transfer porting is on the 800 engine compared to a lamey....and is the yamaha powervalve just as good or better than a sea doo rave valves....just curious!?

That is the main question, the port timing. However it does not seem to be as much of an issue as you would think. Same with the powervalve. On groupK's BB kit the valves are set in a fixed position or removed b/c it makes enough power at 927cc's to not really need powervalves. Plus the 800's have a problem with dropping valves into the cylinder anyway so it eliminates that issue. Evidentally they are getting the 800 to accelerate along side the gp1200 and the gains are quite significant throughout the RPM's. My interest is peaked with this package thus far!!??:sneaky:But how does this work in a stand up?????

 

[waxhead]

I have some novi carbs for a 800 yammie engine
if anyone wants them then $650 takes them away