Skip to content
  • Recent
  • Tags
  • Popular
  • Users
  • Groups
Skins
  • Light
  • Cerulean
  • Cosmo
  • Flatly
  • Journal
  • Litera
  • Lumen
  • Lux
  • Materia
  • Minty
  • Morph
  • Pulse
  • Sandstone
  • Simplex
  • Sketchy
  • Spacelab
  • United
  • Yeti
  • Zephyr
  • Dark
  • Cyborg
  • Darkly
  • Quartz
  • Slate
  • Solar
  • Superhero
  • Vapor

  • Default (Slate)
  • No Skin
Collapse
Brand Logo

DT125R FORUM

  1. Home
  2. Technical Zone
  3. Engine
  4. Took head off after breakdown

Took head off after breakdown

Scheduled Pinned Locked Moved Engine
33 Posts 7 Posters 6.0k Views
  • Oldest to Newest
  • Newest to Oldest
  • Most Votes
Reply
  • Reply as topic
Log in to reply
This topic has been deleted. Only users with topic management privileges can see it.
  • ZrakoZ Offline
    ZrakoZ Offline
    Zrako
    wrote on last edited by
    #4

    Which seal is it?

    1979 Jawa Mustang 50
    2003 Gilera DNA 125 R.I.P
    2015 Keeway TX 125 SM
    2006 Yamaha DT 125 X

    1 Reply Last reply
    0
    • L Offline
      L Offline
      louis
      wrote on last edited by
      #5

      The piston looks like you went to lean.
      Google "lean piston" and you see many like them.

      1 Reply Last reply
      1
      • CalumC Calum

        Did you replace the crankshaft seal?

        If so did you have it on the right way round?

        ZrakoZ Offline
        ZrakoZ Offline
        Zrako
        wrote on last edited by
        #6

        @Calum googled it , no I didnt. Used the old ones.

        1979 Jawa Mustang 50
        2003 Gilera DNA 125 R.I.P
        2015 Keeway TX 125 SM
        2006 Yamaha DT 125 X

        CalumC 1 Reply Last reply
        0
        • ZrakoZ Zrako

          @Calum googled it , no I didnt. Used the old ones.

          CalumC Offline
          CalumC Offline
          Calum
          wrote on last edited by
          #7

          @Zrako It looks incredibly oily.

          I thought you said you rebuilt the engine sorry?

          It's hard to say what the problem is, although if it's lost gearbox oil, and oil was in the crank case and the piston is filthy, then it could have been the crank seal.

          Always Originate, Never Pirate!

          ZrakoZ 1 Reply Last reply
          0
          • CalumC Calum

            @Zrako It looks incredibly oily.

            I thought you said you rebuilt the engine sorry?

            It's hard to say what the problem is, although if it's lost gearbox oil, and oil was in the crank case and the piston is filthy, then it could have been the crank seal.

            ZrakoZ Offline
            ZrakoZ Offline
            Zrako
            wrote on last edited by
            #8

            @Calum yes I did rebuilt it like 3 months ago I think. Gonna get the seals and replace them soon . I have a spare mitaka piston , but both looks slightly different than the one before. Will post a pics tomorrow...

            1979 Jawa Mustang 50
            2003 Gilera DNA 125 R.I.P
            2015 Keeway TX 125 SM
            2006 Yamaha DT 125 X

            CalumC 1 Reply Last reply
            0
            • ZrakoZ Zrako

              @Calum yes I did rebuilt it like 3 months ago I think. Gonna get the seals and replace them soon . I have a spare mitaka piston , but both looks slightly different than the one before. Will post a pics tomorrow...

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

              @Zrako So what did you rebuild exactly? If you used old components then that might be the problem. I think they're only a couple of quid and for the sake of them I'd just replace them.

              Always Originate, Never Pirate!

              1 Reply Last reply
              0
              • ZrakoZ Offline
                ZrakoZ Offline
                Zrako
                wrote on last edited by Zrako
                #10

                @Calum My bottom end bearing gone before so I got the new conrod and piston , got the crank rebuilt , used new gaskets and fasteners, new clutch plates and springs,installed kickstart ,new oil and waterless coolant... same big one pipe as I had before but in good condition... Thats it basically.

                1979 Jawa Mustang 50
                2003 Gilera DNA 125 R.I.P
                2015 Keeway TX 125 SM
                2006 Yamaha DT 125 X

                CalumC 1 Reply Last reply
                0
                • ZrakoZ Zrako

                  @Calum My bottom end bearing gone before so I got the new conrod and piston , got the crank rebuilt , used new gaskets and fasteners, new clutch plates and springs,installed kickstart ,new oil and waterless coolant... same big one pipe as I had before but in good condition... Thats it basically.

                  CalumC Offline
                  CalumC Offline
                  Calum
                  wrote on last edited by
                  #11

                  @Zrako what! And you didn't replace the crank seals? For the few quid and two seconds it takes?

                  If the big end bearong went then it's likely that it took the seals with it. I would replace both of, which means splitting the cases unfortunately.

                  Always Originate, Never Pirate!

                  ZrakoZ 1 Reply Last reply
                  0
                  • CalumC Calum

                    @Zrako what! And you didn't replace the crank seals? For the few quid and two seconds it takes?

                    If the big end bearong went then it's likely that it took the seals with it. I would replace both of, which means splitting the cases unfortunately.

                    ZrakoZ Offline
                    ZrakoZ Offline
                    Zrako
                    wrote on last edited by
                    #12

                    @Calum well ,Im failed again then... never did it before but will remeber that for future. Ordered them now. Thanks for help

                    1979 Jawa Mustang 50
                    2003 Gilera DNA 125 R.I.P
                    2015 Keeway TX 125 SM
                    2006 Yamaha DT 125 X

                    CalumC 1 Reply Last reply
                    0
                    • ZrakoZ Zrako

                      @Calum well ,Im failed again then... never did it before but will remeber that for future. Ordered them now. Thanks for help

                      CalumC Offline
                      CalumC Offline
                      Calum
                      wrote on last edited by
                      #13

                      @Zrako Let's hope this was the failure point.

                      Always Originate, Never Pirate!

                      ZrakoZ 1 Reply Last reply
                      1
                      • CalumC Calum

                        @Zrako Let's hope this was the failure point.

                        ZrakoZ Offline
                        ZrakoZ Offline
                        Zrako
                        wrote on last edited by
                        #14

                        @Calum thinking about build it up again and give it to someone to check and tune it properly as Im lost confidence haha .

                        1979 Jawa Mustang 50
                        2003 Gilera DNA 125 R.I.P
                        2015 Keeway TX 125 SM
                        2006 Yamaha DT 125 X

                        CalumC 1 Reply Last reply
                        0
                        • ZrakoZ Zrako

                          @Calum thinking about build it up again and give it to someone to check and tune it properly as Im lost confidence haha .

                          CalumC Offline
                          CalumC Offline
                          Calum
                          wrote on last edited by
                          #15

                          @Zrako Not really mate. It's so simple and we are here to help.

                          Literally it's the crank seals. Yoy gotta imagine that when the bearings went they would have gone for the softest part of the engine, whih is the seals.

                          Always Originate, Never Pirate!

                          ZrakoZ 1 Reply Last reply
                          0
                          • CalumC Calum

                            @Zrako Not really mate. It's so simple and we are here to help.

                            Literally it's the crank seals. Yoy gotta imagine that when the bearings went they would have gone for the softest part of the engine, whih is the seals.

                            ZrakoZ Offline
                            ZrakoZ Offline
                            Zrako
                            wrote on last edited by
                            #16

                            @Calum yeah , didnt thought about it as I think I checked them , silly mistake. Do you think I will need a new head gasket ? Im did the light skim as you made the tutorial for it , dont know how to identify if the head gasket is bad or reuseable...

                            1979 Jawa Mustang 50
                            2003 Gilera DNA 125 R.I.P
                            2015 Keeway TX 125 SM
                            2006 Yamaha DT 125 X

                            CalumC 1 Reply Last reply
                            0
                            • ZrakoZ Zrako

                              @Calum yeah , didnt thought about it as I think I checked them , silly mistake. Do you think I will need a new head gasket ? Im did the light skim as you made the tutorial for it , dont know how to identify if the head gasket is bad or reuseable...

                              CalumC Offline
                              CalumC Offline
                              Calum
                              wrote on last edited by
                              #17

                              @Zrako Head Gaskets are not reusable.

                              My advice, don't take the head off, but I'm guessing it's too late for that now.

                              Athena head gasket is only a tenner.

                              Always Originate, Never Pirate!

                              1 Reply Last reply
                              1
                              • ZrakoZ Offline
                                ZrakoZ Offline
                                Zrako
                                wrote on last edited by
                                #18

                                Well , here we go again . 2nd rebuild . Now with new crank bearings and seals 🙄 , new piston and rings , new - used clutch , removed kickstart and got new used stay for the sprag clutch and installed starter motor, fresh gear oil.

                                https://youtu.be/b2MZ359Ag3g

                                Here is what it sounds like . First start was surprisingly smooth ,was idling bit higher so turned it down and bled autolube . Feel strange as it was maybe too good to be true lol .
                                Let me know what you think about the sound. Havent jump on it yet btw.

                                1979 Jawa Mustang 50
                                2003 Gilera DNA 125 R.I.P
                                2015 Keeway TX 125 SM
                                2006 Yamaha DT 125 X

                                NINJAN 1 Reply Last reply
                                2
                                • ZrakoZ Zrako

                                  Well , here we go again . 2nd rebuild . Now with new crank bearings and seals 🙄 , new piston and rings , new - used clutch , removed kickstart and got new used stay for the sprag clutch and installed starter motor, fresh gear oil.

                                  https://youtu.be/b2MZ359Ag3g

                                  Here is what it sounds like . First start was surprisingly smooth ,was idling bit higher so turned it down and bled autolube . Feel strange as it was maybe too good to be true lol .
                                  Let me know what you think about the sound. Havent jump on it yet btw.

                                  NINJAN Offline
                                  NINJAN Offline
                                  NINJA
                                  wrote on last edited by
                                  #19

                                  @Zrako Sounds like a 4 stroke with the airbox lid off. LOL

                                  Great job tho!!! 👍

                                  SEDUCED BY THE DARK SIDE!!!

                                  1 Reply Last reply
                                  1
                                  • ZrakoZ Offline
                                    ZrakoZ Offline
                                    Zrako
                                    wrote on last edited by
                                    #20

                                    0_1500242402424_20170716_225845.jpg

                                    0_1500242412618_20170716_225908.jpg

                                    Well , brand new iridium br9eix after like 30 minutes idling. First 5 minutes was bleeding oil pump. Doesnt smoke too much . 🤕

                                    1979 Jawa Mustang 50
                                    2003 Gilera DNA 125 R.I.P
                                    2015 Keeway TX 125 SM
                                    2006 Yamaha DT 125 X

                                    CalumC 1 Reply Last reply
                                    0
                                    • ZrakoZ Zrako

                                      0_1500242402424_20170716_225845.jpg

                                      0_1500242412618_20170716_225908.jpg

                                      Well , brand new iridium br9eix after like 30 minutes idling. First 5 minutes was bleeding oil pump. Doesnt smoke too much . 🤕

                                      CalumC Offline
                                      CalumC Offline
                                      Calum
                                      wrote on last edited by
                                      #21

                                      @Zrako A bit rich, but you won't really tell unless you do a plug chop.

                                      Always Originate, Never Pirate!

                                      1 Reply Last reply
                                      0
                                      • ZrakoZ Offline
                                        ZrakoZ Offline
                                        Zrako
                                        wrote on last edited by
                                        #22

                                        @Calum what exactly does that plug chop is ? Never heard that before

                                        1979 Jawa Mustang 50
                                        2003 Gilera DNA 125 R.I.P
                                        2015 Keeway TX 125 SM
                                        2006 Yamaha DT 125 X

                                        CalumC 1 Reply Last reply
                                        0
                                        • ZrakoZ Zrako

                                          @Calum what exactly does that plug chop is ? Never heard that before

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

                                          @Zrako http://kawtriple.com/mraxl/carb/plugchop.htm

                                          https://www.google.co.uk/search?q=plug+chop&ie=utf-8&oe=utf-8&client=firefox-b-ab&gfe_rd=cr&ei=1eVrWaveI6fA8gf04rnACA

                                          Google my friend.

                                          Always Originate, Never Pirate!

                                          ZrakoZ 1 Reply Last reply
                                          1
                                          Reply
                                          • Reply as topic
                                          Log in to reply
                                          • Oldest to Newest
                                          • Newest to Oldest
                                          • Most Votes


                                          • Login

                                          • Don't have an account? Register

                                          • Login or register to search.
                                          • First post
                                            Last post
                                          0
                                          • Recent
                                          • Tags
                                          • Popular
                                          • Users
                                          • Groups