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  1. #1

    1100 DI port timing?

    Looking for information on the transfer port timing of the DI cylinder. Is it lower timing than the ZXI cylinder?

    I know the exhaust port on the DI is 'much' lower than the ZXI. Are the transfer ports LOWER on a DI cylinder?

  2. #2
    Im not sure there is any difference in the port timing at all. My DI engine had a destroyed cylinder and when ordering a replacement sleave both the DI engine and the ZXI engine call for the same sleave. My cylinders ended up being destroyed and couldnt use them. I called some places and asked if any other engines had interchangeable cylinders with the DI and I was told the ZXI 1100 engine was a direct interchange. After rebuilding the engine, the first day I had it at lake I was warming up engine on trailer and discovered a leak in the shaft seal and couldnt take it out. Got to speaking with a guy at the lake and he told me the port timing was completely different, engine shouldnt even run and even if it did it would have no compression or power. That was 2 years ago, engine has 145 lbs of compression per hole, runs just fine and plenty of power.

    I compared the DI and the ZXI cylinders while I had them off, and while I did not physically measure the port hieghts, I did check all the casting numbers and misc markings on both. Everything matched exactly with the only physical difference being the ZXI cylinders are turqoise and the DI cylinders are cast iron grey.

  3. #3
    Thats interesting because LA Sleeve, Advanced Sleeve, and NW sleeve all have unique Sleeve part numbers. I know that the DI cylidner the exhaust port is lower by a significant amount. That is why that guy would of thought your compression would of been real weak.

  4. #4
    I just looked at the LA Sleeve and Advanced Sleeve websites and I only see 1 part number for each company covering the engines. LA lists part number KA5303 which covers the JT engine 96-03, the JH engine 96-03 and the Ultra 130 DI engine 01-04. Advanced lists part number 3228FA for the same engine family.

  5. #5
    Well I see that too, I mistakenly looked at the piston column where it was unique. Same sleeve can only mean exactly same port timing. But I have seen articles where the talk about lower port timing. Groupk is one I can find quickly

  6. #6
    Yes, the pistons are specific to the DI engine. Although, from working on both the Polaris Ficht engines and the Kawi Ficht engine I believe it is nothing more than an attempt to help atomize the fuel. The Kawi DI pistons have a small dish in the piston right under the injector and I have found some documentation online this was for fuel atomization. Polaris engines did not use the dished piston.

    I have read that tech write up before on the Groupk modifications. Dont know what to tell you, I can assure you I have carb cylinders on my DI engine and it runs just fine. I would also argue the port timing is different as the replacement sleeves all have the exact same part numbers. As I said previously, the guy I ran into at the lake had a race ski and appeared to be very knowledgable about the Kawi engines. He was insistent it wouldnt even run until I showed him it running on the trailer. Then he insisted it would have no compression and probably would not even make enough power to get on a plane. That same day I took the ski home and ran a compression check on it. Brand new engine, maybe 5 minutes of run time on it on trailer and it had 145 psi compression. Ski runs just fine, makes plenty of power and is nearly as fast as my Polaris 1200 injected skis.

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