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  1. #1

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    4 stroke Cylinder Head mods

    Hi all I have a 08 ultra 250x with a stress crack.

    1) I'm looking to have it repaired but need to know who would be the best for that?
    2) I would lik eto have it modified for racing and who would be the best for that?

    I know porting is one option
    I also know that polishing is another but I hear that it can affect fuel atomization, so what else can be done?
    I also found that Pro1racing has a Q4 performance mod to be done which seems pretty intense but also pretty cool as for performance.
    Has anyone used Pro1racing if so how was the service and the results.

    Any other ideas recommendations for modifications to this head?


  2. #2
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    There is no option but to replace the head any repair will fail. Don't waste your money despite what any shop might tell you. Buy a 2010 260x head and this won't happen again

  3. #3

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    How about one thats slightly damaged by piston impact what do you all think or just upgrade to a 260x head?

  4. #4
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    Quote Originally Posted by Droopy View Post
    How about one thats slightly damaged by piston impact what do you all think or just upgrade to a 260x head?
    If it where me id go straight to the 260 head especially if your going to spend the money on porting etc.

  5. #5
    UltraKvz's Avatar
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    I ported my 260 and no gains here.

  6. #6
    dw_1's Avatar
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    porting alone will do jack thats why

    there is alot to benefit from porting provided the rest engine is upto task and with most mods one thing needs another then you spent 5x the money you wanted to all to make the head work usefull so unless you are prepared to lay out some money just do what fire suggested

  7. #7
    nicjak's Avatar
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    been there done that the oem heads are flowed very well from the manufacturer, i didnt notice any gains, plus when the head did crack again kawasaki wouldnt cover it because it had been touched. btw as the engine is also s/c porting will not give any real gains

  8. #8
    UltraKvz's Avatar
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    I did'nt listen to you guys back then when I asked and did it anyway, now I know it does jack! Even on my modified engine!

    Quote Originally Posted by nicjak View Post
    been there done that the oem heads are flowed very well from the manufacturer, i didnt notice any gains, plus when the head did crack again kawasaki wouldnt cover it because it had been touched. btw as the engine is also s/c porting will not give any real gains

  9. #9
    Take the time to smile sirbreaksalot's Avatar
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    Quote Originally Posted by Droopy View Post
    Hi all I have a 08 ultra 250x with a stress crack.

    1) I'm looking to have it repaired but need to know who would be the best for that?
    2) I would lik eto have it modified for racing and who would be the best for that?

    I know porting is one option
    I also know that polishing is another but I hear that it can affect fuel atomization, so what else can be done?
    I also found that Pro1racing has a Q4 performance mod to be done which seems pretty intense but also pretty cool as for performance.
    Has anyone used Pro1racing if so how was the service and the results.

    Any other ideas recommendations for modifications to this head?
    first mod is throw head in the bin and buy a 2010 260x head , as you CAN NOT repair the early heads

    porting a head with out comp or cams and mainly a waste of time because 1 very big factor

    THE POS supercharger it is the main restriction..............

    yes you can get some small gains with porting , just their are better ways to wake the ski up for a lot less money


    Waz

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