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DT125R FORUM

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  4. After some expert help!

After some expert help!

Scheduled Pinned Locked Moved Engine
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  • M Offline
    M Offline
    Mightyman
    wrote on 13 Sept 2017, 10:07 last edited by
    #20

    Unlucky man, glad your unharmed though!

    TDR 125 - 2001

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    • C Offline
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      Calum
      wrote on 13 Sept 2017, 10:36 last edited by
      #21

      It's like, the signs were there. It didn't fail for no reason.

      You see it all the time where people drive their engines to literal death when the bike was telling them it needed investigating.

      Always Originate, Never Pirate!

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      • M Mightyman
        13 Sept 2017, 08:09

        Just had a quick Google and first couple of results suggest worn rings / not correctly sized piston, which makes perfect sense because the sound will be the air squeezing through the ring seal when compression is happening.

        I suppose this means my bikes could have been a bit down on power not having a correctly sized piston 😂

        R Offline
        R Offline
        ricky0115
        wrote on 13 Sept 2017, 10:50 last edited by
        #22

        @mightyman dt125r puff of air from top end didn't find any matches for me😂

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        • R Offline
          R Offline
          ricky0115
          wrote on 13 Sept 2017, 10:56 last edited by ricky0115
          #23

          It's not seized, managed to get it in the garage there's a hole in the piston and some scrapes on the barrel, they advised a full rebuild so I've gone with it. At least it will be done properly and will be under parts warranty!

          There goes my new fat bars & koso digital instruments till next month 😞

          C 1 Reply Last reply 13 Sept 2017, 11:33
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          • R ricky0115
            13 Sept 2017, 10:56

            It's not seized, managed to get it in the garage there's a hole in the piston and some scrapes on the barrel, they advised a full rebuild so I've gone with it. At least it will be done properly and will be under parts warranty!

            There goes my new fat bars & koso digital instruments till next month 😞

            C Offline
            C Offline
            Calum
            wrote on 13 Sept 2017, 11:33 last edited by
            #24

            @ricky0115 And I refer you to my initial prognosis of the problem...

            Who have you taken it to to rebuild it?

            Always Originate, Never Pirate!

            R 1 Reply Last reply 13 Sept 2017, 12:27
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            • C Calum
              13 Sept 2017, 11:33

              @ricky0115 And I refer you to my initial prognosis of the problem...

              Who have you taken it to to rebuild it?

              R Offline
              R Offline
              ricky0115
              wrote on 13 Sept 2017, 12:27 last edited by
              #25

              @calum yep you know your stuff for sure, kudos!

              It's gone to CMC, Yamaha dealer.

              C 1 Reply Last reply 13 Sept 2017, 12:29
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              • R ricky0115
                13 Sept 2017, 12:27

                @calum yep you know your stuff for sure, kudos!

                It's gone to CMC, Yamaha dealer.

                C Offline
                C Offline
                Calum
                wrote on 13 Sept 2017, 12:29 last edited by
                #26

                @ricky0115 Yeah nice. I only ask because these engines MUST (and I can't stress that enough) be built using either genuine or Athena head gasket.

                If they use anything else then it absolutely will blow the head gasket.

                But if they're a genuine Yamaha Dealer then they should be using genuine gasket.

                What piston are you going for?

                A hole being burnt through the piston is a big sign of the bike being incorrectly jetted.

                You've effective welded through the piston.

                Always Originate, Never Pirate!

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                • R Offline
                  R Offline
                  ricky0115
                  wrote on 13 Sept 2017, 13:09 last edited by ricky0115
                  #27

                  I have gone for the wossner? It's was about £70, it's a genuine Yamaha gasket, so the bore will be standard again I guess?

                  I have only had the bike about 2 weeks and I'm new to 2 strokes so I wouldn't have been aware of any jetting issues so I'll make sure it's up to scratch when I get it back! I know it has a 240 main jet but that's about it.

                  Thanks for your help!

                  C 1 Reply Last reply 13 Sept 2017, 14:02
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                  • R ricky0115
                    13 Sept 2017, 13:09

                    I have gone for the wossner? It's was about £70, it's a genuine Yamaha gasket, so the bore will be standard again I guess?

                    I have only had the bike about 2 weeks and I'm new to 2 strokes so I wouldn't have been aware of any jetting issues so I'll make sure it's up to scratch when I get it back! I know it has a 240 main jet but that's about it.

                    Thanks for your help!

                    C Offline
                    C Offline
                    Calum
                    wrote on 13 Sept 2017, 14:02 last edited by
                    #28

                    @ricky0115 Yeah nice. I read on PJME that Wossner were having their parts made in China, but I have Wossners in mine so it's fine.

                    Could be the wrong plug bud, too hot.

                    I would be very inclined to getting a new plug for it as well.

                    It might not be standard size if you have damaged the bore, it'll require a rebore.

                    Always Originate, Never Pirate!

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                    • R Offline
                      R Offline
                      ricky0115
                      wrote on 13 Sept 2017, 14:46 last edited by
                      #29

                      Fair enough, it's the plug recommended in the Haynes manual NGK BR9ES, not sure if the gap was wrong maybe? They do an iridium plug also if they're any better?

                      Any tips on running it in? Is there any way to limit the throttle as my rpm counter doesn't work.

                      C 1 Reply Last reply 13 Sept 2017, 14:48
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                      • R ricky0115
                        13 Sept 2017, 14:46

                        Fair enough, it's the plug recommended in the Haynes manual NGK BR9ES, not sure if the gap was wrong maybe? They do an iridium plug also if they're any better?

                        Any tips on running it in? Is there any way to limit the throttle as my rpm counter doesn't work.

                        C Offline
                        C Offline
                        Calum
                        wrote on 13 Sept 2017, 14:48 last edited by
                        #30

                        @ricky0115 Shouldn't worry about revs, it's more load if anything.

                        Just bed the engine in gently or 100 miles. And vary the throttle after that.

                        It's all about trying not to glaze the rings and cylinder walls.

                        Always Originate, Never Pirate!

                        R 1 Reply Last reply 13 Sept 2017, 18:46
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                        • O Offline
                          O Offline
                          oldman
                          wrote on 13 Sept 2017, 17:08 last edited by
                          #31

                          That's me told! Spot on Calum!

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                          • C Calum
                            13 Sept 2017, 14:48

                            @ricky0115 Shouldn't worry about revs, it's more load if anything.

                            Just bed the engine in gently or 100 miles. And vary the throttle after that.

                            It's all about trying not to glaze the rings and cylinder walls.

                            R Offline
                            R Offline
                            ricky0115
                            wrote on 13 Sept 2017, 18:46 last edited by
                            #32

                            @calum thanks man appreciate it

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