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  4. New purchase 1990 dt125r

New purchase 1990 dt125r

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  • U Offline
    U Offline
    ukchad
    wrote on last edited by
    #9

    Actually had a go at turning the power valve around today - 180 degrees so the top of it was flush with the manifold.

    Took it out and I thought I had knackered it.... until I hit 7000 rpm OMG

    terry.tzT 1 Reply Last reply
    1
    • J Offline
      J Offline
      Jens Eskildsen
      wrote on last edited by
      #10

      Bike getting hot could be headgasket.

      1 Reply Last reply
      0
      • U ukchad

        Actually had a go at turning the power valve around today - 180 degrees so the top of it was flush with the manifold.

        Took it out and I thought I had knackered it.... until I hit 7000 rpm OMG

        terry.tzT Offline
        terry.tzT Offline
        terry.tz
        wrote on last edited by
        #11

        @ukchad mines wide open it's a bit annoying some times but ye its fun
        @Jens-Eskildsen ye people put them on the wrong way round right

        "Muddy water is best cleared by leaving it alone" Alan Watts

        1 Reply Last reply
        0
        • U Offline
          U Offline
          ukchad
          wrote on last edited by
          #12

          Yeah, the head gasket is on my radar.
          The oil looked ok when I changed it - so did the coolant, but I will check the consistency tomorrow.
          How big a job is it to do the head gasket for a garage? Ball park cost? I think that may be a stage too far for me to do yet.

          I actually put the power valve back to original position as the exhaust got very hot very quickly (smoking from end after I stopped after a 5 min blast)

          declanD terry.tzT 3 Replies Last reply
          0
          • U ukchad

            Yeah, the head gasket is on my radar.
            The oil looked ok when I changed it - so did the coolant, but I will check the consistency tomorrow.
            How big a job is it to do the head gasket for a garage? Ball park cost? I think that may be a stage too far for me to do yet.

            I actually put the power valve back to original position as the exhaust got very hot very quickly (smoking from end after I stopped after a 5 min blast)

            declanD Offline
            declanD Offline
            declan
            wrote on last edited by
            #13

            @ukchad might aswell throw a new piston in there while our at it

            1 Reply Last reply
            0
            • O Offline
              O Offline
              oldman
              wrote on last edited by
              #14

              Head refurb really straightforward, just get a decent gasket set, take your time and follow the manual. Did mine while I had the engine out, takes no time really. Nice bike, gotta save these old ones😁

              1 Reply Last reply
              1
              • U ukchad

                Yeah, the head gasket is on my radar.
                The oil looked ok when I changed it - so did the coolant, but I will check the consistency tomorrow.
                How big a job is it to do the head gasket for a garage? Ball park cost? I think that may be a stage too far for me to do yet.

                I actually put the power valve back to original position as the exhaust got very hot very quickly (smoking from end after I stopped after a 5 min blast)

                terry.tzT Offline
                terry.tzT Offline
                terry.tz
                wrote on last edited by
                #15

                @ukchad head is easy best done with a torque wrench thou if you're willing to buy one

                "Muddy water is best cleared by leaving it alone" Alan Watts

                1 Reply Last reply
                1
                • U Offline
                  U Offline
                  ukchad
                  wrote on last edited by
                  #16

                  Another tool to purchase, but I do love having them.

                  declanD 1 Reply Last reply
                  0
                  • U ukchad

                    Yeah, the head gasket is on my radar.
                    The oil looked ok when I changed it - so did the coolant, but I will check the consistency tomorrow.
                    How big a job is it to do the head gasket for a garage? Ball park cost? I think that may be a stage too far for me to do yet.

                    I actually put the power valve back to original position as the exhaust got very hot very quickly (smoking from end after I stopped after a 5 min blast)

                    terry.tzT Offline
                    terry.tzT Offline
                    terry.tz
                    wrote on last edited by
                    #17

                    @ukchad said in New purchase 1990 dt125r:

                    I actually put the power valve back to original position as the exhaust got very hot very quickly (smoking from end after I stopped after a 5 min blast)

                    haha I would say leave it open its boring closed I could fall asleep riding if it was not wide open 😁 but I will say I have seen threads where there is a bit of controversy so think it's best you know how your bike runs first so you will tell if it rich or lean through the rev range

                    "Muddy water is best cleared by leaving it alone" Alan Watts

                    1 Reply Last reply
                    0
                    • U ukchad

                      Another tool to purchase, but I do love having them.

                      declanD Offline
                      declanD Offline
                      declan
                      wrote on last edited by
                      #18

                      @ukchad 0_1502570106995_IMG_1486.JPG

                      Another 1990 welcome! Ignore the sticker bomb and the rear wheel got a puncture in my wheel and chipped paint underneath the sticker bomb lol

                      terry.tzT 1 Reply Last reply
                      1
                      • declanD declan

                        @ukchad 0_1502570106995_IMG_1486.JPG

                        Another 1990 welcome! Ignore the sticker bomb and the rear wheel got a puncture in my wheel and chipped paint underneath the sticker bomb lol

                        terry.tzT Offline
                        terry.tzT Offline
                        terry.tz
                        wrote on last edited by
                        #19

                        @declan coming on that is Declan

                        "Muddy water is best cleared by leaving it alone" Alan Watts

                        declanD 1 Reply Last reply
                        0
                        • O Offline
                          O Offline
                          oldman
                          wrote on last edited by
                          #20

                          Here's one I prepared earlier !
                          0_1502570553952_20170715_131805.jpg

                          U 1 Reply Last reply
                          0
                          • U Offline
                            U Offline
                            ukchad
                            wrote on last edited by
                            #21

                            Is it normal for the exhaust to heat up so much then, when the power valve is fully open?

                            Also died a bit when I kicked up into 6th, ran out of power (maybe wasn't high enough revs)

                            declanD 1 Reply Last reply
                            0
                            • O oldman

                              Here's one I prepared earlier !
                              0_1502570553952_20170715_131805.jpg

                              U Offline
                              U Offline
                              ukchad
                              wrote on last edited by
                              #22

                              @oldman soooo clean

                              1 Reply Last reply
                              0
                              • U ukchad

                                Is it normal for the exhaust to heat up so much then, when the power valve is fully open?

                                Also died a bit when I kicked up into 6th, ran out of power (maybe wasn't high enough revs)

                                declanD Offline
                                declanD Offline
                                declan
                                wrote on last edited by
                                #23

                                @ukchad coming from 4 stroke this was crazy for me I have full functioning pv) my muffler gets too hot to touch

                                1 Reply Last reply
                                0
                                • terry.tzT terry.tz

                                  @declan coming on that is Declan

                                  declanD Offline
                                  declanD Offline
                                  declan
                                  wrote on last edited by
                                  #24

                                  @terry-tz hey thank you buddy nice hearing that much appreciated but a lot to go yet 😊

                                  terry.tzT 1 Reply Last reply
                                  0
                                  • declanD declan

                                    @terry-tz hey thank you buddy nice hearing that much appreciated but a lot to go yet 😊

                                    terry.tzT Offline
                                    terry.tzT Offline
                                    terry.tz
                                    wrote on last edited by
                                    #25

                                    @declan good to know there's more to come

                                    "Muddy water is best cleared by leaving it alone" Alan Watts

                                    1 Reply Last reply
                                    0
                                    • CalumC Offline
                                      CalumC Offline
                                      Calum
                                      wrote on last edited by
                                      #26

                                      Hello and welcome'

                                      Get the servo retro fitted and have a working powervalve. Best of both worlds.

                                      Exhaust gets hotter because you spend longer times at higher rpms. Refer back to my previous statement. Get the servo fitted. Less stress on the engine.

                                      I would start simple first, check the thermostat, they are probe to failing after zo many years.

                                      Head gasket is not the same as a four stroke. No valves no nothing to go wrong.

                                      Buy only genuine or athena gasket, skim the head like described in my tutorial, then boom, good to go.

                                      Nice bike.

                                      Always Originate, Never Pirate!

                                      declanD U 2 Replies Last reply
                                      0
                                      • MiniaM Offline
                                        MiniaM Offline
                                        Minia
                                        wrote on last edited by
                                        #27

                                        Welcome, looking good 🙂

                                        Yamaha DT125R Blue 2002, XT 125 1982, Yamaha WR250Z 1992, BMW GS650F 1994, Benelli BN302 2015

                                        1 Reply Last reply
                                        0
                                        • CalumC Calum

                                          Hello and welcome'

                                          Get the servo retro fitted and have a working powervalve. Best of both worlds.

                                          Exhaust gets hotter because you spend longer times at higher rpms. Refer back to my previous statement. Get the servo fitted. Less stress on the engine.

                                          I would start simple first, check the thermostat, they are probe to failing after zo many years.

                                          Head gasket is not the same as a four stroke. No valves no nothing to go wrong.

                                          Buy only genuine or athena gasket, skim the head like described in my tutorial, then boom, good to go.

                                          Nice bike.

                                          declanD Offline
                                          declanD Offline
                                          declan
                                          wrote on last edited by
                                          #28

                                          @calum what's skimming the head do I know squish and compression etc but does just that on its own yield noticeable results?

                                          1 Reply Last reply
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