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  4. What damage have I done?

What damage have I done?

Scheduled Pinned Locked Moved Engine
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  • M Offline
    M Offline
    Matt47
    wrote on last edited by
    #14

    I had another look at the bike this evening, and although nothing looks to have gone top end - there is a lot of play on the connecting rod. Side play tolerances I have not looked up yet, but i'm almost certain that there shouldn't be at least 2mm play up and down!!

    If that's gone south and it means splitting the engine is this cost effective or am I flogging a dead horse? Would be such a shame as I really love the little beast!

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    • CalumC Online
      CalumC Online
      Calum
      wrote on last edited by
      #15

      Yep not a problem mate.

      There should be no up and down play. And little side to side play is to be expected and within tolerance.

      Sounds like the engine needs to be stripped down.

      Again this is standard practice for two strokes and is incredibly simple job to do.

      No real specialist tools required othwr than the crank will need to be sent away for a rebuild.

      The rest of the engine can be rebuilt at home.with basic tools. Only a flywheel puller, clutch holding tool, torque wrench and a rubber mallet will be needed.

      The bearings can be removed and inserted by placing the engine in the oven for a few minutes and letting the metal expand which will release the bearings. The rest is just simple stuff.

      The most complicated bits will be rebalancing the engine. Which is self explanatory. Just matxh up the notches on the primary drive vogs. And balancing the clutch, which I have documeted here.

      After thay it is just a case of using decent gaskets and genuine or Athena headgasket. Personally I would buy a full Athena engine gasket. And take lots of photos.

      Simple.job

      Always Originate, Never Pirate!

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      • M Offline
        M Offline
        Matt47
        wrote on last edited by
        #16

        OK well it looks like I will be doing a crash course in mechanics then!

        So apart from the tools you listed, is this what I should be getting?

        Full gasket set (Athena)
        All bearings
        Piston kit
        Crank rebuilt

        Thinking about it, do I also need to take cylinder somewhere to be measured/checked incase of re-bore?

        Thanks,
        Matt

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        • CalumC Online
          CalumC Online
          Calum
          wrote on last edited by
          #17

          I would get the cylinder honed against a new piston. You will need to have a new piston to hone against. I would let whoever is doing the honing buy the piston. Or ask them if it needs a rebore. If they say no then buy the same sized piston.

          There is probably a few tools I missed off the list. A good set of spanners and screwdrivers. So nuts and bolts to replace the ones you use is not s bad should.

          Always Originate, Never Pirate!

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          • M Offline
            M Offline
            Matt47
            wrote on last edited by
            #18

            OK cheers. So I guess first step is to take top end into a bike shop and let them sort that out if it needs work done. Then I know what size piston I need (if they don't do it).

            New bolts sounds like a good idea too, hadn't thought of that!

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            • CalumC Online
              CalumC Online
              Calum
              wrote on last edited by
              #19

              Yeah, get it to a shop and ask if you will be fine with a hone. In my experience you don't tend to save much money by buying the piston yourself.

              I mean sure, if you can get the piston cheaper then by all means. But the risk of buying the wrong one could outweigh the savings you might make.

              Always Originate, Never Pirate!

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              • M Offline
                M Offline
                Matt47
                wrote on last edited by Matt47
                #20

                OK so not much progress since last post, but I have now at least removed engine from the frame...

                Still not made it to a shop to check cylinder, but have ordered a flywheel puller and made up a holding tool for clutch/flywheel which I'm chuffed with!

                All prepped and ready to operate after a good clean. B-)

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                • CalumC Online
                  CalumC Online
                  Calum
                  wrote on last edited by
                  #21

                  Nice, keep us posted. Any problems throw up a thread. ☺

                  Always Originate, Never Pirate!

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                  • M Offline
                    M Offline
                    Matt47
                    wrote on last edited by
                    #22

                    Well I finally got myself organised and have everything ready for the rebuild 7 months later! :-S

                    Crank has been rebuilt (not by me!), barrel/head skimmed, powervalve cleaned, got full seal kit and full Athena gasket kit ready to go... Now I just need to remember where everything goes. :-))

                    CalumC 1 Reply Last reply
                    1
                    • M Matt47

                      Well I finally got myself organised and have everything ready for the rebuild 7 months later! :-S

                      Crank has been rebuilt (not by me!), barrel/head skimmed, powervalve cleaned, got full seal kit and full Athena gasket kit ready to go... Now I just need to remember where everything goes. :-))

                      CalumC Online
                      CalumC Online
                      Calum
                      wrote on last edited by
                      #23

                      @Matt47 it's fairly straight forward but do shout if you need help.

                      Always Originate, Never Pirate!

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                      • M Offline
                        M Offline
                        Matt47
                        wrote on last edited by
                        #24

                        Ok, so my next silly question is... How do I remove seals the correct way to avoid damaging anything?!
                        Think I have read that you can use screws to give yourself something to pull on - is this correct? Not keen on digging them out with a flat-head (unless they pop out easily).

                        You can probably tell I'm a bit nervous about the whole thing, guess I need to man up haha! 😛

                        CalumC 1 Reply Last reply
                        0
                        • M Matt47

                          Ok, so my next silly question is... How do I remove seals the correct way to avoid damaging anything?!
                          Think I have read that you can use screws to give yourself something to pull on - is this correct? Not keen on digging them out with a flat-head (unless they pop out easily).

                          You can probably tell I'm a bit nervous about the whole thing, guess I need to man up haha! 😛

                          CalumC Online
                          CalumC Online
                          Calum
                          wrote on last edited by
                          #25

                          @Matt47 I always had access to the seals from behind. Aka if they are the main bearing seals then removing the main bearings will give you access to them.

                          Always Originate, Never Pirate!

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                          • M Offline
                            M Offline
                            Matt47
                            wrote on last edited by
                            #26

                            Ah, makes sense thanks!

                            There was me thinking I had everything on my rebuild list, and I forgot to get the other bearings...

                            All remaining bearings seem to be in great shape, but I guess I need to weigh up whether or not to do a full rebuild without all new bearings. Is it worth the risk?!

                            CalumC 1 Reply Last reply
                            0
                            • M Matt47

                              Ah, makes sense thanks!

                              There was me thinking I had everything on my rebuild list, and I forgot to get the other bearings...

                              All remaining bearings seem to be in great shape, but I guess I need to weigh up whether or not to do a full rebuild without all new bearings. Is it worth the risk?!

                              CalumC Online
                              CalumC Online
                              Calum
                              wrote on last edited by
                              #27

                              @Matt47 What bearings need replacing?

                              The gearbox bearings cost 20 quid. It would be silly not to sort those out st that price.

                              If I were splitting the cases then I would just replace the bearings. But that's me.

                              Always Originate, Never Pirate!

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                              • M Offline
                                M Offline
                                Matt47
                                wrote on last edited by
                                #28

                                I only have the 2 main bearings for Crankshaft, and the top end stuff.

                                I'll have to commandeer the oven once my wife has gone to bed, and get them all out and have a proper look at them! They all feel/look in good nick but I might as well take them out anyway to make the seals easier to change.

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                                • CalumC Online
                                  CalumC Online
                                  Calum
                                  wrote on last edited by
                                  #29

                                  As said, for their cost I'd do the gearbox bearings.

                                  Always Originate, Never Pirate!

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                                  0
                                  • M Offline
                                    M Offline
                                    Matt47
                                    wrote on last edited by
                                    #30

                                    Yeah I suppose so, especially after seeing the post on gearbox bearings (quarter of the price of what I can find in France - and that includes postage from UK).

                                    Disappointed that I overlooked these when ordering, but it would annoy me more if I didn't do it right after it has sat in bits for 7 months plus!

                                    Cheers for all your support mate, will hopefully get them ordered up soon.

                                    1 Reply Last reply
                                    1
                                    • CalumC Online
                                      CalumC Online
                                      Calum
                                      wrote on last edited by
                                      #31

                                      Simplybearings yeah? Grab all th Koyo bearings

                                      Always Originate, Never Pirate!

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                                      • M Offline
                                        M Offline
                                        Matt47
                                        wrote on last edited by
                                        #32

                                        Yeah, that's the one - amazing value once you know what to look for! €105 for 2 genuine Crank bearings or €28 for 2 koyo shielded (which were what mine were).

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                                        • M Offline
                                          M Offline
                                          Matt47
                                          wrote on last edited by
                                          #33

                                          Tonight I heated up the crankcase halves to remove the bearings, and got all out apart from the 2 in the picture.

                                          http://i1377.photobucket.com/albums/ah75/MatthewT47/20150124_144844_zpsnakligp9.jpg

                                          How do I go about getting these out, as they are only accessible from one side?

                                          Cheers, Matt

                                          ps. sorry about the date on pic lol,

                                          CalumC 1 Reply Last reply
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