650/X-2 750 or 800 bore on a 650 ?

[Dutchie]

Hello,

I want to tune the sh*t out of my 650 engine haha and i want to make a frankenstein.

I have read that the 750 small pin ? top end fits on a 650 low end? With 4mm stroke issue?

I also see people that have this setup, but how is it done and what do i have to do. It's easyer for me to make a frankenstein then to buy a complete engine because over here we dont have a lot of parts for sale..

I want to go the biggest for the best buck. maybe make a 800 sxr topend on a 650 lowend? or a 750 smallpin cause it has the lower port timing..

I just want low end power. I know that there will be clearances issues but what will it be. Hope to get awnsers from some one that did it. Picktures and links to site's and forums from people who did it wil be sweet!

Thanks peeps!

 

[Vumad]

Have you bought a pipe yet?

To answer your question, it's a complete waste of money to do what you suggest. Buy an 800 motor and have it worked.

Lets be realistic for just one moment. You started your line of questioning on this forum with "Cheap backflip X2" or some variation of that. There's nothing cheap about a single thing you want to do. The things you want to do require specific machines to do the work and a vast amount of knowledge you do not have. Since you wont be able to do any of the things you want to do to a reasonable level of quality, you will have to pay someone to do the work.

Basic port, polish, etc etc of a shortblock only is $1000. A big bore top end w/ agressive porting and no bottom end work is about $2000-3000. The cost of a worked stroker motor is much higher. The cost of the insanity of tuning you just asked about is well out of your price range. If it were in your price range, you would have already called Xscream, Jetmaniac, Dasa, etc and they would have gladly taken your money to tell you you're crazy to work a 650 motor like that, and then they'd give you a 1000cc motor.

The above just covers the short block. They doesn't include the $1000 carbs, $1500 pipe, $500 lightened flywheel or $1500 total loss system, or countless thousands it'd cost you to own a hull worth putting those items in.

I appriciate your ambition, but the things you want cost money. Lots of money.

You need to buy a westcoast 650 pipe with manifold, a 44mm mikuni carb with manifold, have your flywheel lightened, your head milled, your waterbox drilled or replaced and a new "swirl" prop.

Pipe $300
carb/intake $100
Flywheel service $75
Head work $75
Waterbox drilled $20
Prop $200

That's about $800 + shipping.

A 750 motor will cost about $600 shipped, and that may be complete with carbs and electronics. A 800 motor, $1000. That's why noone touches a 650 anymore.

But seriously. Have you bought a pipe?

 

[Vumad]

650 pistons 76mm
750 pistons 80mm

650 stroke 70mm
750 stroke 74mm

 

[Dutchie]

Hey,

I am seriousr. I just dont know the pecs of these engines. I do my oen porting machening by a colleg of me.
I have my own garage, i build cars, scooters and rec. Racing engines. Offcourse can it be done cheap, nothing comes free but by building My own engine it will become cheaper than having It done.

I dont want the westcoast. Thinking of buying a coffman or factory. And sinds i havedesigned several preforming championship 2 stroke exhaust i am thinking of building 2 pipes for One ski. Why is dis not done on all pipes ? or is the supersonic freqienci balanced out in one pipe. This i dont underatand.

And i am someone that builds and likes to make stuff for My hobby's hehe.

I also have my eye on a complete sx 750. This will be my donor.

Gr,

 

[Dutchie]

The flip was just a quistion :l and i will do It someday

 

[GrantWarden]

Why don't you just buy the 750 and build it up? It'll kill the 650 in every way.
>Sell 650.
>Buy 750.
>Use money from 650 to buy pipe, intake mani, exhaust mani, carbs, flywheel, and prop.
>Ride ski.
You have spoken about your experience with cars, what you are talking about doing is like putting a Corvette engine in a Pinto. Basically, the 650 hull is fairly terrible, and the engine lacks a lot of power. For the price of a new engine, you could sell the 650 and buy something decent.

 

[Dutchie]

A Corvette engine in a pinto could be cool hahaha ( just kiddin)

Now normally i would say also buy a 750 but there are so many things to read on the internet.

The principle of this engine is not the deal, its just that this is my first kawi 650 and i dont know nothing about timing of other engines of kawi. Normal road engines i can dream what is good and what not haha This is a whole new ball game for me. ( the finding out what i need for my needs part)

I have been reading that 650 have good low end
750 bigpin good high speed (12bolted intake)
750 smallpin great low and (10 bolted intake)
800 sxr great high speed

So i think i need to get the 750 small pin.. Or make a frankenstein with a bigpin case for the bearings and a smallpin top end for the low end power.

That will be a nice project dont you guy's think? O have an idea?

Thank you all

 

[feartheride]

Sure you know this but you can run 650 electronics on a 750 motor, you just need to machine the 3 spots in the front of the case to accept the stator plate from the 650 as the 750 was mounted on the cover not the case..

 

[mydixiewrecked]

Putting a small pin cylinder on a big pin bottom works well. not really a frankenstein builf

 

[Dutchie]

I love making frankensteins haha every engine that has parts from this and that gets that name from me hehe.

I have my eye on a complete 750sx, so the electricks will be set then.

But the 750 can be drilled out to max 800 ? I see 857cc engines but they have a stroker kit? That wil go to far for the extra's. Just making the best of what i can do with the 750 will be fine.

And the jetpump, what to do with this for a resonable buck? get a 750 pump in the x2?

Greetings friends

 

[chriselmore_1]

Forget the big bore motor! All you need is a swirl prop to backflip!

 

[Dutchie]

Are you in me now ? Haha seriously ? Explain yourself

 

[iangdesign]

Do you a little more research...you don't have to stick with a Kawi engine in your ski. Rad Dudes make a bed plate so the Yami engines will fit into the hull on the stock motor mounts.

This opens up a world more possibilities for you, being some engines aren't available to you. I bet there is a fair amount of yami skis in the Netherands. 701s, 760s, 800s.

Just a thought. But yeah, Frankensteining an engine is going to be about the same cost wise as just buying something you know already works and runs properly.

 

[Dutchie]

I dit a lot of research.. for what i can fond the kawa engines give a littel more low end power. The kawa ski,s are good for racing and the superjets are nicer for freestyle..

I just love the x2 and kawas are cheaper to find than superjets. I got My eye on Two kawas over here both 750's. One.cheap One that runs and One that is Nice with what i think is a racing exhaust on it. One of them i will buy then use It for parts.

But now Need to find out what i will do for tuning. I love the ada heads. And a factory pipe or coffmans amd.some duals on there, i read online that those setups fly !

Maybe a 750 pump on there with a swirl prop but i dont know if the 750 pumps are better than a 650 pumps ?

Gr,