What engine to put in 650sx build?

[njrealtor55]

i have a junk 650sx hull. i was thinking about putting a seadoo 787 engine in it, but the engine alignment is thrown way off when the starter is installed. the pump would have to get moved up into the tray area and massive reconstruction would have to be done to get the pump and engine straight(not worth it).

so.....

i heard people put 750 motors in them, but has anyone put something else into it? anyone heard of another motor fitting - or know of something that may fit?

i am looking for a good project - something that will have a lot of power - almost silly - (like a gp1200 engine in a RN superjet that i saw). the 787 would have been great because i have tons of seadoo stuff.

if i get a engine in there i will mold in tubbies, foot holds & rear hull extensions to make the ski easier to ride.

if anyone thinks they could help with alignment of the seadoo 787 in the 650sx, i would be greatful. as of now, i am stumped.

 

[felix5oh]

Just put a rocket engine in it and smash it against the rocks.




Now ,go find a sj hull and put your mind to work.

 

[Jake6488]

Nah man dont listen to those sj guys. I ride a 650sx also. Altho i am getting ready to start a sn build. But yeah just put a 800 motor in it. Itl rip. But yeah man good luck

 

[ANT]

an sxr 800 motor or a 750 motor would fit into it. all you need to do is fit the 650 electrics on the 800 motor. That would be your best bet.

Don't put all that effort into a 650sx. Don't do anything more than simple bolt on's/ drop in's. You will find that it's not worth it. The amount of time and money you put into that ski to make it good you could spend on a superjet which would be 10 times more versatile than that ski.

Don't get me wrong though my first ski was a 93' 650SX with a westcoast pipe, mariner head, 44mm carb, and 15.5 skat prop, but after having a superjet and even an sxr, i wouldn't want one again for anything more than crusing around the back bays with once in a while and for friends to ride.

 

[Melmack]

Agree here. That was my first ski too. Lot's of fun till I got my SJ. The 650 sx hull is wayyy to heavy for it's size. One suggestion though is to ditch that tiny carb and drop a cheap 44 on it. That makes a huge difference on the stock 650. Any more work than that is a waste of time and money IMO. Would have been a cool freestyle hull if it was lighter weight though.

 

[WFO Speedracer]

The 650SX is lighter than a Superjet by quite a bit,I am not going to say it is a good freestyle boat without a lot of work though.

 

[Melmack]

I tried to verify the weight but could not find the specs anywhere. Anyone know how much they weigh? I think all the ones I've had must have been waterlogged. But I don't see why it isn't a good freestyle boat. It slides well, it dose hood tricks well. If it really is lighter, that's a bonus. An 800 can bolt right in with no modding needed. Not to mention the 650 is a really good freestyle motor with a little work. Many of them came with 28mm single carbs. That's an easy fix. They have a very short stroke and light flywheel making them very quick. I'm not sure but I think the pump is basicaly the same as the 800 so it can handle lots of upgrades and modern props ect. So, why isn't it a good buget freestyle boat?

 

[whitca]

So, why isn't it a good buget freestyle boat?

I think it's a great freeride boat even on a budget. When it was all said and done, I spent equally as much as a friend building a SJ but did a lot more because the parts for the 650 were cheaper. Depending on what you want to do, there is a lot more custom fabbing due to the limited availability of aftermarket freeride parts. It's all how much time you want to spend.

 

[whitca]

if i get a engine in there i will mold in tubbies, foot holds & rear hull extensions to make the ski easier to ride.

If your making this a freestyle ski, bag the hull extensions, shorten the pole or convert it to a roundnose pole and shorten it. The stock pole feels REALLY long and once you get your center of gravity closer to the engine coupled with tubbies the ski is cake to ride.

 

[WFO Speedracer]

Yes get rid of the stock pole that is where all the weight is.