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    Cylinder questions

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    • Irongamer727
      Irongamer727 last edited by

      Correct me if I am wrong, but the Dt cylinder are made from aluminium right? But they have no nikasil coating? What are the inside coated with then? Explain someone!

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      • Calum
        Calum last edited by

        The Athena kits are plated. The stock cylinders are lined with steel bores.

        Always Originate, Never Pirate!

        Irongamer727 1 Reply Last reply Reply Quote 0
        • Irongamer727
          Irongamer727 @Calum last edited by

          @calum I know it's a VERY debated question. But in theory, you mean the Athena kit would need little or no running in?

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          • Calum
            Calum last edited by

            It's mating the rings to the cylinder walls. You're forcing dissimilar materials against each other. Not only that, components wear together. Nothing is perfect, so the walls have imperfections, as do the rings. You want to gently mate the two items. When you refresh the rings, you're mating a worn bore to new rings. This will aggravate the components, care must be taken to again mate the components.

            We're talking thousandths of an inch, but at 12,000 rpm, you want to be damn sure they're near perfect.

            Always Originate, Never Pirate!

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            • Irongamer727
              Irongamer727 last edited by Irongamer727

              So this is the cylinder and perhaps piston I'm going to substitute my Athena kit with.
              The cylinder is in fantastic condition (or so I think) and the piston as well.

              They should be reusable right? No need for a new piston either?

              Piston and cylinder substitute https://imgur.com/a/zldHrxx

              Calum 1 Reply Last reply Reply Quote 0
              • Calum
                Calum @Irongamer727 last edited by

                @irongamer727 I'd have the bore honed and a new set of rings.

                Those rings looks like they could benefit from being replaced. Grab a new gudgeon pin and small end bearing. Don't forget to replace the circlips.

                Always Originate, Never Pirate!

                Irongamer727 1 Reply Last reply Reply Quote 0
                • Irongamer727
                  Irongamer727 @Calum last edited by

                  @calum why hone? It's not even worn

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                  • Irongamer727
                    Irongamer727 last edited by

                    The pictures don't make it far, I'll have to admit.

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                    • Irongamer727
                      Irongamer727 last edited by

                      Where can I find good rings, a new gudgeon pin and circlips?

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                      • 2
                        2stroketerry last edited by

                        Personaly i would get it bored to the next size as don't know how many miles the piston has done. Also regarding the bore you should have the cross hatching from the cylinder being honed but not any vertical up and down scratches like that cylinder has on it. If you don't mind me asking how much is the barrel and piston? How much are you wanting to spend as i have a spare barrel thats been fully ported and a fresh rebore on it to 57.5mm with a Mitaka piston. Also a spare set of rings with it as well as a brand new genuine Yamaha little end bearing. Has a 3MB head with it thats been skimmed and matched to the ported barrel with the correct swish and compression on it and an Athena head gasket with it that has been alterd to suit the 1.5mm larger bore size. Will post some pictures if your interested.

                        Irongamer727 D 2 Replies Last reply Reply Quote 0
                        • Irongamer727
                          Irongamer727 @2stroketerry last edited by

                          @2stroketerry I bought an entire engine for £85, the cylinder came with it. I'm thinking about trying this guy. https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F401431331293

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                          • 2
                            2stroketerry last edited by

                            Hi, yes a few people on this forum have had there barrels re bored by him and said his work is good and you won't find anyone cheaper.

                            Irongamer727 declan 2 Replies Last reply Reply Quote 0
                            • Irongamer727
                              Irongamer727 @2stroketerry last edited by

                              @2stroketerry so it's worth a try?

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                              • declan
                                declan @2stroketerry last edited by

                                @2stroketerry just out of curiosity how much is that barrel set up for sale for?

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                                • Calum
                                  Calum last edited by

                                  I wpould go to PJME for my stuff.

                                  The hone is just a refresh to restore the crosshatching. I disagree about the rebore unless its out of round, but a decent honing place can decide this for you and order the piston in.

                                  Always Originate, Never Pirate!

                                  Irongamer727 1 Reply Last reply Reply Quote 0
                                  • Irongamer727
                                    Irongamer727 @Calum last edited by

                                    @calum £96 for postage with piston, rebore and all that feels pretty good.

                                    Calum 1 Reply Last reply Reply Quote 0
                                    • Calum
                                      Calum @Irongamer727 last edited by

                                      @irongamer727 From PJME?

                                      Always Originate, Never Pirate!

                                      Irongamer727 1 Reply Last reply Reply Quote 0
                                      • Irongamer727
                                        Irongamer727 @Calum last edited by

                                        @calum ehhm no, that eBay guy

                                        Calum 1 Reply Last reply Reply Quote 0
                                        • Calum
                                          Calum @Irongamer727 last edited by

                                          @irongamer727 Oh ryt. Well is the piston any good?

                                          I'd recommend PJME as they're the best in the business. Nothing beats the best.

                                          Always Originate, Never Pirate!

                                          Irongamer727 1 Reply Last reply Reply Quote 0
                                          • Irongamer727
                                            Irongamer727 @Calum last edited by

                                            @calum well if it were me I'd just buy new rings, gudgeon pin and small end and use everything.

                                            Calum 1 Reply Last reply Reply Quote 0
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