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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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  • ricky0115R ricky0115

    How do you mean? just run with it in gear?

    CalumC Offline
    CalumC Offline
    Calum
    wrote on last edited by
    #6

    @ricky0115 No damage, it can cause bore wash but I doubt there will be any problems here.

    Choke on to start, then once the revs die down, take the choke off and that's it.

    Always Originate, Never Pirate!

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    • ricky0115R Offline
      ricky0115R Offline
      ricky0115
      wrote on last edited by
      #7

      Thanks I will give it a go.

      Any idea on the carb overflow? Tried tapping the float end in case it was jammed but no luck. Thinking about taking it to a garage and having all the seals replaced. Noticed a threaded bolt on the reed block, would this cause an air leak?

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      • ricky0115R Offline
        ricky0115R Offline
        ricky0115
        wrote on last edited by
        #8

        Okay so I just tried kicking it up and on the third kick I heard a puff of air like a blow off valve letting out pressure but I'm unsure where it came from it sounded like it was somewhere near the carb or air filter

        CalumC 1 Reply Last reply
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        • ricky0115R ricky0115

          Okay so I just tried kicking it up and on the third kick I heard a puff of air like a blow off valve letting out pressure but I'm unsure where it came from it sounded like it was somewhere near the carb or air filter

          CalumC Offline
          CalumC Offline
          Calum
          wrote on last edited by
          #9

          @ricky0115 Probably tried to fire up but failed.

          You haven't blown a hole through the piston have you? It does start right?

          Always Originate, Never Pirate!

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          • ricky0115R Offline
            ricky0115R Offline
            ricky0115
            wrote on last edited by
            #10

            @Calum It will only start from bumping it, I'm going to take it to the garage on thursday so I will update with the issue.

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            • MightymanM Offline
              MightymanM Offline
              Mightyman
              wrote on last edited by
              #11

              A couple of my bikes used to occasionally make that sound when I was kicking them. I'm sure it only happens on an engine that isn't perfectly set up / running little bit lean or little bit rich? Either way the bikes ran okay.

              TDR 125 - 2001

              declanD 1 Reply Last reply
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              • MightymanM Mightyman

                A couple of my bikes used to occasionally make that sound when I was kicking them. I'm sure it only happens on an engine that isn't perfectly set up / running little bit lean or little bit rich? Either way the bikes ran okay.

                declanD Offline
                declanD Offline
                declan
                wrote on last edited by
                #12

                @mightyman I've only known 4 strokes to make that sound

                ricky0115R 1 Reply Last reply
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                • A Offline
                  A Offline
                  andrewj1680
                  wrote on last edited by
                  #13

                  I'd say piston rings at a guess maybe just a cracked ring would cause issues

                  ricky0115R 1 Reply Last reply
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                  • A andrewj1680

                    I'd say piston rings at a guess maybe just a cracked ring would cause issues

                    ricky0115R Offline
                    ricky0115R Offline
                    ricky0115
                    wrote on last edited by
                    #14

                    @andrewj1680 thanks

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                    • declanD declan

                      @mightyman I've only known 4 strokes to make that sound

                      ricky0115R Offline
                      ricky0115R Offline
                      ricky0115
                      wrote on last edited by
                      #15

                      @declan I think it's drawing in way too much air, everything is standard air intake wise. How can I find the piston size I know it's been bored out but I'm unsure of the size

                      O 1 Reply Last reply
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                      • ricky0115R ricky0115

                        @declan I think it's drawing in way too much air, everything is standard air intake wise. How can I find the piston size I know it's been bored out but I'm unsure of the size

                        O Offline
                        O Offline
                        oldman
                        wrote on last edited by
                        #16

                        @ricky0115 markings on top of the piston should give you the size or measure the bore with calipers, either way it's the head off, not a big deal. Personally think your problem lies elsewhere but expect to be proved wrong, see what the garage says, hopefully something simple. Good luck

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                        • MightymanM Offline
                          MightymanM Offline
                          Mightyman
                          wrote on last edited by
                          #17

                          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 😂

                          TDR 125 - 2001

                          ricky0115R 1 Reply Last reply
                          0
                          • NottsbikerN Offline
                            NottsbikerN Offline
                            Nottsbiker
                            wrote on last edited by
                            #18

                            I've had this before on a high mileage DT125R and due to being poor I left it with dire consequences. Basically the piston tried to make its way out via the exhaust port. I went from a standard bore to 2.00mm oversize in one go which made me cry when I realised.

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                            • ricky0115R Offline
                              ricky0115R Offline
                              ricky0115
                              wrote on last edited by
                              #19

                              Yeah I just tried to ride to work and the engine died doing 60 the back wheel locked up I have never been so scared in my life! I think it's ready for a new top end! Actually anyone selling a wr200 engine?😂

                              Cheers guys

                              1 Reply Last reply
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                              • MightymanM Offline
                                MightymanM Offline
                                Mightyman
                                wrote on last edited by
                                #20

                                Unlucky man, glad your unharmed though!

                                TDR 125 - 2001

                                1 Reply Last reply
                                0
                                • CalumC Offline
                                  CalumC Offline
                                  Calum
                                  wrote on 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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                                  • MightymanM Mightyman

                                    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 😂

                                    ricky0115R Offline
                                    ricky0115R Offline
                                    ricky0115
                                    wrote on last edited by
                                    #22

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

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                                    • ricky0115R Offline
                                      ricky0115R Offline
                                      ricky0115
                                      wrote on 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 😞

                                      CalumC 1 Reply Last reply
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                                      • ricky0115R ricky0115

                                        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 😞

                                        CalumC Offline
                                        CalumC Offline
                                        Calum
                                        wrote on 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!

                                        ricky0115R 1 Reply Last reply
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                                        • CalumC Calum

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

                                          Who have you taken it to to rebuild it?

                                          ricky0115R Offline
                                          ricky0115R Offline
                                          ricky0115
                                          wrote on last edited by
                                          #25

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

                                          It's gone to CMC, Yamaha dealer.

                                          CalumC 1 Reply Last reply
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