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Thread: When to replate cylinder

  1. #1
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    When to replate cylinder

    Recently I had a YZ-250 cylinder re-plated for a customer, after just a couple of outings he leaned down the methanol fuel mixture and stuck it. Being new to plated cylinders I do not know what damage to the plating is acceptable and at what point it becomes un usable...

    Overall the cylinder cleaned up very well.... The exception is an area on the bridge between the boost port and transfer port where a small flake of plating has come off. The ring end gap is in the center of the void. 1st thought was to remove material from the sharp edges where the rings pass over the void.
    If any one has experience running a cylinder with similar damage any input would be greatly appreciated.....

    Click image for larger version. 

Name:	YZ250 chrome flake.jpg 
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    The picture view is from the base of the cylinder looking up on the intake side.
    The void in the plating is on the left bridge as shown in the picture.

  2. #2
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    17th April 2006 - 05:39
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    Quote Originally Posted by 2005bully View Post
    Recently I had a YZ-250 cylinder re-plated for a customer, after just a couple of outings he leaned down the methanol fuel mixture and stuck it. Being new to plated cylinders I do not know what damage to the plating is acceptable and at what point it becomes un usable...

    Overall the cylinder cleaned up very well.... The exception is an area on the bridge between the boost port and transfer port where a small flake of plating has come off. The ring end gap is in the center of the void. 1st thought was to remove material from the sharp edges where the rings pass over the void.
    If any one has experience running a cylinder with similar damage any input would be greatly appreciated.....

    Click image for larger version. 

Name:	YZ250 chrome flake.jpg 
Views:	57 
Size:	764.0 KB 
ID:	334806
    The picture view is from the base of the cylinder looking up on the intake side.
    The void in the plating is on the left bridge as shown in the picture.
    You'll have to re do it mate. The ring end gap will catch, even if you use a dremmel to smooth that flake off.

  3. #3
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    13th June 2010 - 17:47
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    In the days before replating was readily available, i would have vee'd that out and kept using the barrel...
    Now that it is available, I realise that Vee'ing it out stuffs it for replating....

    Tell him to bite the bullet and get it done - and find a 2nd barrel as a spare.

  4. #4
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    Quote Originally Posted by Grumph View Post
    Now that it is available, I realise that Vee'ing it out stuffs it for replating....

    .
    Nah, they'll be able to fill the hole and re plate it no prob.

  5. #5
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    Oh well

    It looks like re-plating is the general consensus. The rest of the cylinder looks so good.... Oh well. Thanks for the advice.

  6. #6
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    Quote Originally Posted by Crasherfromwayback View Post
    Nah, they'll be able to fill the hole and re plate it no prob.
    Certainly - but it elevates it to a much higher degree of difficulty. Once welded, it's got to be round and true before plating.
    If it's distorted as a result of the weld, better hope it cleans up at a size you can find pistons for....

  7. #7
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    Id be asking who plated it to redo it they charge enough . Shouldint flake of at all . Unless it was cleaned enough in that area . I was looking at sending my ns 250 r cylinders of to the only nz company i am aware of .as one my cylinders has nasty scuff around the exhust port .


    Sent from my iPhone using Tapatalk

  8. #8
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    Quote Originally Posted by 2005bully View Post
    after just a couple of outings he leaned down the methanol fuel mixture and stuck it. .
    Quote Originally Posted by actungbaby View Post
    Id be asking who plated it to redo it they charge enough . k
    Yeah, nah.

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