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  1. #1
    MADRUI madrui's Avatar
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    what are the best pistons to replace the stock ones for a ultra 250x?

    i broke my stock ultras pistons and i want to put new ones but im not shore what to put.can somebody help me?
    my ultra have the 6 degree timing advance the rest is stock and i only can use normal gas here in portugal the best is 98oct.
    thanks


  2. #2
    Fat Man, Little Boat Region8Ultra250X's Avatar
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    why dont you figure out what caused the stock ones to break first? this is the first i've heard of a stock piston breaking..... especially if the only thing you have done is the 6 degree timing advance.... have you recently had any pump problems?

  3. #3
    MADRUI madrui's Avatar
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    not that i know.but im going to ask my mechanic but here in portugal is dificult to have a good one.
    the only problem that i had was with the charger and i fixed it and after like 4 hours the ski lost power and start to make smoke.it only broke the 1 piston other are good.iwas thynking to put the 260 ones or the je.but i want the ski for recriational use so only pump gas. thanks

  4. #4

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    many here would recommend the stock 260 pistons!

  5. #5
    nicjak's Avatar
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    +1 for reliability

    Quote Originally Posted by KawaHead View Post
    many here would recommend the stock 260 pistons!

  6. #6

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    Oh.. I forgot... maybe the new 300 pistons would be better if you can get hold of them.. dunno if they fit yet as the new 300 pistons have a thinner crown and shallower deck relief but with same compression ratio of 8.4:1. It also has a shorter skirt area to decrease mechanical drag and weight!

  7. #7
    MADRUI madrui's Avatar
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    for me i would consider to put the 300x pistons but are alot of diferences on the compression because of the charger i think but im not a guy that understand alot about engines.again thanks for the inputs

  8. #8
    nicjak's Avatar
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    wtf are you thinking the ski isnt even available yet so i doubt whether dealers are stocking parts. and all the information you are obtaining is third hand.

    Quote Originally Posted by KawaHead View Post
    Oh.. I forgot... maybe the new 300 pistons would be better if you can get hold of them.. dunno if they fit yet as the new 300 pistons have a thinner crown and shallower deck relief but with same compression ratio of 8.4:1. It also has a shorter skirt area to decrease mechanical drag and weight!

  9. #9

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    mark my words!

  10. #10
    Take the time to smile sirbreaksalot's Avatar
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    Quote Originally Posted by madrui View Post
    i broke my stock ultras pistons and i want to put new ones but im not shore what to put.can somebody help me?
    my ultra have the 6 degree timing advance the rest is stock and i only can use normal gas here in portugal the best is 98oct.
    thanks
    if you only intend on changing pistons and not spending a lot of endless money on your ski .

    then the ONLY option for you is the OEM 09 260 piston !!!!!!!!!!!!!!!!!!!
    unless someone makes a 9.0:1 set of forged slugs yet.........( that would be a good rec combo ) but sadly they dont.

    bolt in fit no tuning if you are runnig a Stock supercharger pullies, 100 percent reliable

    I have seen many 07,08 pistons crack even on stock skiies
    the 09 has INCREASED crown thickness that assists in strengthining the piston as well as raising the Static Compression ratio.


    Waz

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