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  4. Whats a good carburetor for my DT125 with a 170cc athena cylinder kit?

Whats a good carburetor for my DT125 with a 170cc athena cylinder kit?

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carburetor
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  • CalumC Calum

    36 is HUGE!

    that will be horrendous on fuel!

    clawsC Offline
    clawsC Offline
    claws
    wrote on last edited by
    #5

    @Calum it is already because my ypvs is locked to the up right position and the carburetor isnt in perfect tune

    2̶0̶0̶4̶ ̶D̶T̶1̶2̶5̶R̶E̶ ̶w̶i̶t̶h̶ ̶s̶u̶p̶e̶r̶m̶o̶t̶o̶ ̶w̶h̶e̶e̶l̶s̶ ̶a̶n̶d̶ ̶a̶ ̶1̶7̶0̶c̶c̶ ̶a̶t̶h̶e̶n̶a̶ ̶k̶i̶t̶
    1999 YZ250 with a 1999 DTR VIN

    CalumC 1 Reply Last reply
    0
    • clawsC claws

      @Calum it is already because my ypvs is locked to the up right position and the carburetor isnt in perfect tune

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

      @claws Well you've definitely got more money than me.

      Once upon a time my brother ran a kehien 38 on his 170 Athena. The fueling was mental and the performance did not match.

      That's just my advice, you don't have to take it. Bigger is not always better. You'd do well to lower it to get more performance and fuel economy.

      My brother is currently running a 34mm on a 170cc two stroke, and he's looking at a 28mm for more performance and better economy.

      Always Originate, Never Pirate!

      clawsC 1 Reply Last reply
      0
      • CalumC Calum

        @claws Well you've definitely got more money than me.

        Once upon a time my brother ran a kehien 38 on his 170 Athena. The fueling was mental and the performance did not match.

        That's just my advice, you don't have to take it. Bigger is not always better. You'd do well to lower it to get more performance and fuel economy.

        My brother is currently running a 34mm on a 170cc two stroke, and he's looking at a 28mm for more performance and better economy.

        clawsC Offline
        clawsC Offline
        claws
        wrote on last edited by
        #7

        @Calum i cant really tune my current carb and i dont have that much money haha

        2̶0̶0̶4̶ ̶D̶T̶1̶2̶5̶R̶E̶ ̶w̶i̶t̶h̶ ̶s̶u̶p̶e̶r̶m̶o̶t̶o̶ ̶w̶h̶e̶e̶l̶s̶ ̶a̶n̶d̶ ̶a̶ ̶1̶7̶0̶c̶c̶ ̶a̶t̶h̶e̶n̶a̶ ̶k̶i̶t̶
        1999 YZ250 with a 1999 DTR VIN

        CalumC 1 Reply Last reply
        0
        • clawsC claws

          @Calum i cant really tune my current carb and i dont have that much money haha

          CalumC Offline
          CalumC Offline
          Calum
          wrote on last edited by
          #8

          @claws You're throwing good money after bad, a few jets is considerably cheaper than a 36mm carb. Besides, do you really think slapping on a carb will make your bike run right?

          Fueling is no something you scrimp on, run it lean, and you'll run into detonation destroying both the bottom and top end. So don't scrimp on fueling.

          Always Originate, Never Pirate!

          clawsC 1 Reply Last reply
          1
          • CalumC Calum

            @claws You're throwing good money after bad, a few jets is considerably cheaper than a 36mm carb. Besides, do you really think slapping on a carb will make your bike run right?

            Fueling is no something you scrimp on, run it lean, and you'll run into detonation destroying both the bottom and top end. So don't scrimp on fueling.

            clawsC Offline
            clawsC Offline
            claws
            wrote on last edited by
            #9

            @Calum getting the keihin for 60 euros isnt a bad deal besides the screws for the carburetor are seized so i cant mess with the float or jets. also i can just sell the carb if i need to. im not an expert at tuning carbs but i can make it run ok

            2̶0̶0̶4̶ ̶D̶T̶1̶2̶5̶R̶E̶ ̶w̶i̶t̶h̶ ̶s̶u̶p̶e̶r̶m̶o̶t̶o̶ ̶w̶h̶e̶e̶l̶s̶ ̶a̶n̶d̶ ̶a̶ ̶1̶7̶0̶c̶c̶ ̶a̶t̶h̶e̶n̶a̶ ̶k̶i̶t̶
            1999 YZ250 with a 1999 DTR VIN

            CalumC 1 Reply Last reply
            0
            • clawsC claws

              @Calum getting the keihin for 60 euros isnt a bad deal besides the screws for the carburetor are seized so i cant mess with the float or jets. also i can just sell the carb if i need to. im not an expert at tuning carbs but i can make it run ok

              CalumC Offline
              CalumC Offline
              Calum
              wrote on last edited by
              #10

              @claws It needs to run spot on, is my point. Even the new carb will need jetting.

              Always Originate, Never Pirate!

              O clawsC 2 Replies Last reply
              1
              • CalumC Calum

                @claws It needs to run spot on, is my point. Even the new carb will need jetting.

                O Offline
                O Offline
                oldman
                wrote on last edited by
                #11

                @Calum said in Whats a good carburetor for my DT125 with a 170cc athena cylinder kit?:

                @claws It needs to run spot on, is my point. Even the new carb will need jetting.

                I second that

                1 Reply Last reply
                0
                • CalumC Calum

                  @claws It needs to run spot on, is my point. Even the new carb will need jetting.

                  clawsC Offline
                  clawsC Offline
                  claws
                  wrote on last edited by
                  #12

                  @Calum gonna get it running great. better than with the original carb

                  2̶0̶0̶4̶ ̶D̶T̶1̶2̶5̶R̶E̶ ̶w̶i̶t̶h̶ ̶s̶u̶p̶e̶r̶m̶o̶t̶o̶ ̶w̶h̶e̶e̶l̶s̶ ̶a̶n̶d̶ ̶a̶ ̶1̶7̶0̶c̶c̶ ̶a̶t̶h̶e̶n̶a̶ ̶k̶i̶t̶
                  1999 YZ250 with a 1999 DTR VIN

                  CalumC 1 Reply Last reply
                  1
                  • clawsC claws

                    @Calum gonna get it running great. better than with the original carb

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

                    @claws That's great to hear! I know from experience going too big is detrimental. But maybe I didn't spend enough time tweaking it!

                    Always Originate, Never Pirate!

                    clawsC 1 Reply Last reply
                    0
                    • CalumC Calum

                      @claws That's great to hear! I know from experience going too big is detrimental. But maybe I didn't spend enough time tweaking it!

                      clawsC Offline
                      clawsC Offline
                      claws
                      wrote on last edited by
                      #14

                      @Calum wouldnt be making any sense to not get it running great. gonna send a video of it running later

                      2̶0̶0̶4̶ ̶D̶T̶1̶2̶5̶R̶E̶ ̶w̶i̶t̶h̶ ̶s̶u̶p̶e̶r̶m̶o̶t̶o̶ ̶w̶h̶e̶e̶l̶s̶ ̶a̶n̶d̶ ̶a̶ ̶1̶7̶0̶c̶c̶ ̶a̶t̶h̶e̶n̶a̶ ̶k̶i̶t̶
                      1999 YZ250 with a 1999 DTR VIN

                      DartyD 1 Reply Last reply
                      0
                      • clawsC claws

                        @Calum wouldnt be making any sense to not get it running great. gonna send a video of it running later

                        DartyD Offline
                        DartyD Offline
                        Darty
                        wrote on last edited by
                        #15

                        @claws alt text

                        Not to sound boring, but, Keihin PWK 36mm of a KDX220

                        Been there done that, mental, makes no sense. Actually slower overall..

                        A 32mm can be spot on, if you like to 'hoon' constantly, but these engines are fussy to jet on a bigger carb, I don't recommend it.

                        Keep it real

                        CalumC clawsC 2 Replies Last reply
                        3
                        • DartyD Darty

                          @claws alt text

                          Not to sound boring, but, Keihin PWK 36mm of a KDX220

                          Been there done that, mental, makes no sense. Actually slower overall..

                          A 32mm can be spot on, if you like to 'hoon' constantly, but these engines are fussy to jet on a bigger carb, I don't recommend it.

                          CalumC Offline
                          CalumC Offline
                          Calum
                          wrote on last edited by
                          #16

                          @Darty Long time no post 😛

                          Always Originate, Never Pirate!

                          1 Reply Last reply
                          0
                          • DartyD Darty

                            @claws alt text

                            Not to sound boring, but, Keihin PWK 36mm of a KDX220

                            Been there done that, mental, makes no sense. Actually slower overall..

                            A 32mm can be spot on, if you like to 'hoon' constantly, but these engines are fussy to jet on a bigger carb, I don't recommend it.

                            clawsC Offline
                            clawsC Offline
                            claws
                            wrote on last edited by
                            #17

                            @Darty cant be slower than now though

                            2̶0̶0̶4̶ ̶D̶T̶1̶2̶5̶R̶E̶ ̶w̶i̶t̶h̶ ̶s̶u̶p̶e̶r̶m̶o̶t̶o̶ ̶w̶h̶e̶e̶l̶s̶ ̶a̶n̶d̶ ̶a̶ ̶1̶7̶0̶c̶c̶ ̶a̶t̶h̶e̶n̶a̶ ̶k̶i̶t̶
                            1999 YZ250 with a 1999 DTR VIN

                            CalumC DartyD 2 Replies Last reply
                            0
                            • clawsC claws

                              @Darty cant be slower than now though

                              CalumC Offline
                              CalumC Offline
                              Calum
                              wrote on last edited by
                              #18

                              @claws You'd be surprised.

                              I'm not going into the specifics.

                              But Pressure=force/area

                              The force is generated via the vacuum of the engine, the area is the size of the carb.

                              If the carb increases sizes, but the vacuum remains the same then you will see a drop in pressure. Aka, the pressure to actuate the carb will lower and it may not be as effective, sine the carb works off the venturi effect, getting this balance right is important. Going too big can have adverse affects. Is 36mm too big? I'm not saying that, I'm just saying bigger is not always better.

                              Always Originate, Never Pirate!

                              clawsC 1 Reply Last reply
                              1
                              • CalumC Calum

                                @claws You'd be surprised.

                                I'm not going into the specifics.

                                But Pressure=force/area

                                The force is generated via the vacuum of the engine, the area is the size of the carb.

                                If the carb increases sizes, but the vacuum remains the same then you will see a drop in pressure. Aka, the pressure to actuate the carb will lower and it may not be as effective, sine the carb works off the venturi effect, getting this balance right is important. Going too big can have adverse affects. Is 36mm too big? I'm not saying that, I'm just saying bigger is not always better.

                                clawsC Offline
                                clawsC Offline
                                claws
                                wrote on last edited by
                                #19

                                @Calum of course a bigger carburetor isnt always better but i dont think that i can go slower with the keihin and if i cant get it to run great with the bike i will trade it for a smaller one. but a guy that i know put a 38mm carb in his 1998 dt125r and said that it runs great. still i believe that the new carburetor will out perform the one i have now but if it doesnt i will be a bit disappointed but anyways i wont lose anything with this new carb

                                2̶0̶0̶4̶ ̶D̶T̶1̶2̶5̶R̶E̶ ̶w̶i̶t̶h̶ ̶s̶u̶p̶e̶r̶m̶o̶t̶o̶ ̶w̶h̶e̶e̶l̶s̶ ̶a̶n̶d̶ ̶a̶ ̶1̶7̶0̶c̶c̶ ̶a̶t̶h̶e̶n̶a̶ ̶k̶i̶t̶
                                1999 YZ250 with a 1999 DTR VIN

                                1 Reply Last reply
                                0
                                • CalumC Offline
                                  CalumC Offline
                                  Calum
                                  wrote on last edited by
                                  #20

                                  Oh yeah! Report back to us your findings 😃

                                  Always Originate, Never Pirate!

                                  1 Reply Last reply
                                  1
                                  • clawsC claws

                                    @Darty cant be slower than now though

                                    DartyD Offline
                                    DartyD Offline
                                    Darty
                                    wrote on last edited by Darty
                                    #21

                                    @claws True, but don't forget you'll make less power under 6-8k Rpm.

                                    @Calum lol I don't have much to say about these bikes anymore

                                    Keep it real

                                    clawsC CalumC declanD NINJAN 4 Replies Last reply
                                    1
                                    • DartyD Darty

                                      @claws True, but don't forget you'll make less power under 6-8k Rpm.

                                      @Calum lol I don't have much to say about these bikes anymore

                                      clawsC Offline
                                      clawsC Offline
                                      claws
                                      wrote on last edited by
                                      #22

                                      @Darty doesnt matter. it doesnt have much torque in the lower rpms but its because my ypvs is locked to the up right position. gonna get it resolved as well and maybe get an athena pipe for the bike since its made for the 170cc cylinder kit

                                      2̶0̶0̶4̶ ̶D̶T̶1̶2̶5̶R̶E̶ ̶w̶i̶t̶h̶ ̶s̶u̶p̶e̶r̶m̶o̶t̶o̶ ̶w̶h̶e̶e̶l̶s̶ ̶a̶n̶d̶ ̶a̶ ̶1̶7̶0̶c̶c̶ ̶a̶t̶h̶e̶n̶a̶ ̶k̶i̶t̶
                                      1999 YZ250 with a 1999 DTR VIN

                                      1 Reply Last reply
                                      0
                                      • Glynn123G Offline
                                        Glynn123G Offline
                                        Glynn123
                                        wrote on last edited by
                                        #23

                                        Jetting a none standard carb on a DT is a ballache, 32mm polini pwk didn't make my DT much faster at all without any supporting mods like ignition etc. The fuel usage was well over double too even with both carbs appropriately jetted.

                                        1 Reply Last reply
                                        0
                                        • DartyD Darty

                                          @claws True, but don't forget you'll make less power under 6-8k Rpm.

                                          @Calum lol I don't have much to say about these bikes anymore

                                          CalumC Offline
                                          CalumC Offline
                                          Calum
                                          wrote on last edited by
                                          #24

                                          @Darty Join the club. But most of us talk about different projects these days.

                                          Always Originate, Never Pirate!

                                          clawsC 1 Reply Last reply
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