650/X-2 Wanting to know what are some good power adding mods

[Hayden20]

I am rebuilding my dads 1991 Kawasaki 650sx as a surprise and was wandering what are some good power adding parts for this jetski I don’t want it to be extreme just a little more power sense he’s gotten bigger sense the last time he rode It he was sixteen he’s 45 now and I don’t have a very big budget and I’m using my graduation money to get parts

 

[Quinc]

shave the head, lower pitched impeller, exhaust, tune the carb.

 

[Hayden20]

shave the head, lower pitched impeller, exhaust, tune the carb.

Thanks man how much should I shave the head, I also just got a new old stock keihin 38mm considering the old one was shot any recommendation on jet size

 

[Midlake Crisis]

Thanks man how much should I shave the head, I also just got a new old stock keihin 38mm considering the old one was shot any recommendation on jet size

Newmiller Machine has a niche thing going on old Kawis, knows exactly what to do at a good price. Contact Chris at NMachine@Earthlink.net good guy great service.

 

[Quinc]

Use the same jets out of your old one. You will need to search around on shaving it but probably 3-5 thou.

 

[SXIPro]

I know nothing about 650s, but as a Dad, let me tell you , that is probably gonna be the best gift your old man ever got. Your post gave me some hope for humanity. I just want to hug my own son right now.

 

[Hayden20]

I know nothing about 650s, but as a Dad, let me tell you , that is probably gonna be the best gift your old man ever got. Your post gave me some hope for humanity. I just want to hug my own son right now.

Thank you so much it’s sad how most people I’ve asked for help has said just buy him a new one but I said what’s the point he even has a picture hung up in his office of him riding it for the first time at sun rise with his silhouette and when I give it to him I’m gonna take off at the opposite side of the lake at sun rise so he can see that shadow again and give him apart of his childhood back

 

[Scott Wilson]

awesome! put straight bars on it and new grips. not power options but its a small amount of money well spent.

 

[Midlake Crisis]

I put SJ bars on mine, the stock bars have a weird angle to me.

 

[badvinny]

Thanks man how much should I shave the head, I also just got a new old stock keihin 38mm considering the old one was shot any recommendation on jet size

Check the squish with solder, cut the head leaving .040" minimum, pretty safe if you leave it at .050".

 

[TheBuzzard]

91 and newer 650s came with the bigger carb and higher compression already.
if the motor is tired and rings leak, raising the comp just lets more blow by into the cases. it don't need a shaved head.
a pipe adds the biggest bang for your buck.
when you add motor power, the stock prop will not be the greatest.
a 15 or 15.5 pitch is a good budget prop.
a low variable pitch prop would be better but may not get one for cheap.

 

[Hayden20]

91 and newer 650s came with the bigger carb and higher compression already.
if the motor is tired and rings leak, raising the comp just lets more blow by into the cases. it don't need a shaved head.
a pipe adds the biggest bang for your buck.
when you add motor power, the stock prop will not be the greatest.
a 15 or 15.5 pitch is a good budget prop.
a low variable pitch prop would be better but may not get one for cheap.

Thanks been so busy lately but I just installed new pistons im considering porting the block and polishing my dad rode this jetski for a better part of 4 years every day to go see his girlfriend which was my mom so I asked my grandad how many hours he said at least 2000 hours never rebuilt

I am rebuilding my dads 1991 Kawasaki 650sx as a surprise and was wandering what are some good power adding parts for this jetski I don’t want it to be extreme just a little more power sense he’s gotten bigger sense the last time he rode It he was sixteen he’s 45 now and I don’t have a very big budget and I’m using my graduation money to get parts

I am rebuilding my dads 1991 Kawasaki 650sx as a surprise and was wandering what are some good power adding parts for this jetski I don’t want it to be extreme just a little more power sense he’s gotten bigger sense the last time he rode It he was sixteen he’s 45 now and I don’t have a very big budget and I’m using my graduation money to get parts

 

[Rushford_Ripper]

I have a 650 NOS Mariner 15 impeller if interested in going that route and a Mariner intake grate.

 

[Hayden20]

I have a 650 NOS Mariner 15 impeller if interested in going that route and a Mariner intake grate.

Was there a noticeable difference

 

[Rushford_Ripper]

I meant if you had interest for your ski.

 

[wmazz]

I am rebuilding my dads 1991 Kawasaki 650sx as a surprise

IMO, Long term reliability is important for our toys.

For that reason, I recommend spending more money on a few items. Try to find OEM
main seals that are still in their Kawasaki packaging.

Keihin carbs develop hard starting problems. If you are going to purchase a rebuild
kit, purchase a genuine Keihin kit. They are expensive ~ $80, maybe more. Sudco is
where I purchased my kits at, and Sudco is a Keihin distributor. Use Polaris composite
gaskets instead of Kawasaki. Keihins have a vacuum leak on the carb base gasket that
contributes to hard starting. You could use the Polaris gasket, or I have instructions
for flat sanding the carb during an overhaul.

Don't replace the oem spring inside the carburetor. Set the lever height to 1mm below
the gasket surface. Make sure the needle doesn't leak, and don't worry about the pop-off
psi.

IMO, a choke is more reliable than a primer. A primmer is just a bandaide, it will fix the
symptom, but not the problem. And they wear out.


If you are planning on keeping the X2 stock, Then 15, and 15.5 will improve your X2.
It will help get you on plane quickly and have decent pull. A 650 TS exhaust manifold will
also help your stock engine.

But they are not a good impeller, if you want to purchase, or have an aftermarket exhaust
pipe because they will prevent the engine from making peak horsepower.

Keep in mind you will need a 650 TS exhaust manifold or an aftermarket exhaust manifold
for the pipe.

a low variable pitch prop would be better but may not get one for cheap.

A good overall impeller is the Skat Trak 8/16. Impeller choice is important for reliability


Bill M.

 

[Zach_x2]

can you use the 650ts ex manifold on a x2 with stock exhaust? im assuming so. Is it worth it? I want more power but not really looking to purchase an expensive exhaust pipe

 

[X2Kid]

I used to buy up seized SX 650’s back in the day for a pittance. I always bought modified one’s and stripped off all the performance parts for reuse. It might be worth trying to track down something similar where you are - it sure beat paying for the gear separately.