Question about 2002 Yamaha YZ 426 F

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Piston shot to 3 pieces cylinder damaged,hadnt been fitted properly by previous owner 15yr old needs help doing enduro on sat

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  • hollywood601 Sep 10, 2009

    Which would be best solution cheaply,to have cylinder fixed or buy new 1 ?

  • yadayada
    yadayada May 11, 2010

    u willneed to buy a factory service manual, contact he dealer, about $100



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I would sugest that you bought a cylinder works kit....they are made in china but the importer wish is pivot works supply good product and we even instal theyre big bore kit and they last...(they come with cylinder,pistons and gasket) ....they are very unexpensive.... otherwise if you only have some small aluminium spot from the piston stock on the wall of you're cylinder i sugest that you bought some muriatic acid to get it of ( take good care because this product is hazardous) just apply to where the aluminium stand and scratch a little with sand paper til it goes may have méchanic experience to fix that thing and i sugest you bought a clymer that is way cheaper than that yamaha manual and they have all the info.

Posted on Sep 14, 2009

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Buddy its not an easy job to do as if the barrel has been damaged that much it will have to rebored to an over size piston or a new sleeve installed or if its just a little scratch you can get some glass paper and run it around the barrel not stying in 1 place at the same time do this until smooth also you can take it to a shop and get them to rehone it for you or rebore it also when you put the new one in oil the rings and make sure the arrow is pointing towards the exhaust valve

Posted on Sep 10, 2009


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SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

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