900 zxi too slow-help

[JoeCoastie]

Hi I'm new to the PWC family

I own a 95 Kawasaki ZXI 750 and 900. both stock

My 750 screams but the 900 has a horrible time getting up out of the water and moving which makes no sense seeing as the engine is bigger. Weight maybe?

Any suggestions on upgrades, A/M parts or anything else helpful to get this ski screaming out of the water and past 50 MPH?

I looked all over the web and didn't get answers.

Thanks

[n737rp]

Re: 900 zxi too slow-help

Have you checked your compression on all three cylinders, I would start there, you should have at least 110 or higher on all three, if you have one low one you need to investigate.

[n737rp]

Re: 900 zxi too slow-help

you shouldnt need any aftermarket accesories for that ski to get past 50mph, it should hit that no problem stock. The weight of the ski, will not effect it that much.

[JoeCoastie]

Re: 900 zxi too slow-help

I did the compression test without warming them up first and got 105 in one cylinder and 100 in the other two.

I tested my 750 for laughs and got 145 in both cylinders. My manual says 185 is the norm for the 750.

I'm taking them to the lake tomorrow and I'm going to run the test again after the engines have been running all day and report back.

If I don't find a change Does that mean I need new pistons and gaskets?

Thanks again for the help it's very much appreciated.

[n737rp]

Re: 900 zxi too slow-help

Well having 100 and 105 psi is kinda low, i would say it is on the border line to having a top end done on it, im not telling you that you should, but if you choose to, it will need new pistons and rings, and check the cylinder diameter with a micrometer to see how much wear there is.

[JoeCoastie]

Re: 900 zxi too slow-help

Tested compression again after running them in the lake and i got 90 in two and 95 in one. I'm going to go ahead and rip the engine apart to see if i can find signs of damage. I'm hoping i can get away with new rings and a gasket. pistons are too expensive for me at the moment.

thanks again

[Technical Support]

Re: 900 zxi too slow-help

Joe , you might not find any major issues, the motor might just be tired.