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Athena 170cc questions

Scheduled Pinned Locked Moved Engine
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  • Irongamer727I Irongamer727

    Allright. Every part has arrived. Now. Once I installed the kit and put a big main jet and lowered the needle(more fuel). Should I start it and ride 500 km with the settings way off?( way to much fuel) Or should I lower the jetting until he rides okay? Thing is I don't won't to put any stress on him when the kit just has been installed. How would you do?

    CalumC Offline
    CalumC Offline
    Calum
    wrote on last edited by
    #19

    @irongamer727 You're going to want to ensure you jet it properly and ride it accordingly.

    Always Originate, Never Pirate!

    declanD 1 Reply Last reply
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    • CalumC Calum

      @irongamer727 You're going to want to ensure you jet it properly and ride it accordingly.

      declanD Offline
      declanD Offline
      declan
      wrote on last edited by declan
      #20

      @calum is he not planning on jetting it?oh I see just by banging a main jet in don’t necessarily mean it’s correct as all bikes are different and it’s a pretty precise task

      CalumC 1 Reply Last reply
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      • declanD declan

        @calum is he not planning on jetting it?oh I see just by banging a main jet in don’t necessarily mean it’s correct as all bikes are different and it’s a pretty precise task

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

        @declan Main jet only affects 3/4 to wide open throttle, so no, he's not jetting it properly.

        The jets need to be changed to accomodate the whole rev range.

        Always Originate, Never Pirate!

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        • declanD declan

          @irongamer727 sorry I know you are asking important questions but did you just refer to your bike as a “him”

          O Offline
          O Offline
          oldman
          wrote on last edited by
          #22

          @declan said in Athena 170cc questions:

          @irongamer727 sorry I know you are asking important questions but did you just refer to your bike as a “him”

          Haha haha! Careful, this day and age your bike should be "gender neutral", don't force sexuality on your bike, let it choose or you are going to be on Jeremy Kyle!

          Irongamer727I 1 Reply Last reply
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          • Irongamer727I Offline
            Irongamer727I Offline
            Irongamer727
            wrote on last edited by
            #23

            Read my question again. I'm going to jet it. I know 90% of people use either a 270 or 280 main jet. My plan is to adjust the needle. (As rich as possible) and put a 290 jet in to begin with. But I presume 290 will be to big. It's just to be on the safe side. The tricky part is that I cannot just rev him and see if 290 is to big right? Not until the cylinder has done about 500 km. So either I drive the first 500km with a way to big jet and risk destroying the spark plug and stuff due to the co2 build up. Or I try reving him early to adjust him before the 500 km. That's the dilemma.

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            • O oldman

              @declan said in Athena 170cc questions:

              @irongamer727 sorry I know you are asking important questions but did you just refer to your bike as a “him”

              Haha haha! Careful, this day and age your bike should be "gender neutral", don't force sexuality on your bike, let it choose or you are going to be on Jeremy Kyle!

              Irongamer727I Offline
              Irongamer727I Offline
              Irongamer727
              wrote on last edited by
              #24

              @oldman the bike do have male characteristics 😉

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              • CalumC Offline
                CalumC Offline
                Calum
                wrote on last edited by
                #25

                Yeah I read it.

                Did Athena not provide the correct jettings with the Cylinder kit. That is my gribe.

                How could they develop a kit and then not recommend some jettings for it lol.

                If we're talking all honesty here.

                Get her running sweet on idle, not in gear (you can rev the nuts off it and it won't damage anything provided there is oil) and just make sure it's all good.

                Then run her in gently, then sort the jetting out on WOT using the described plug chop methd.

                Always Originate, Never Pirate!

                1 Reply Last reply
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                • Irongamer727I Offline
                  Irongamer727I Offline
                  Irongamer727
                  wrote on last edited by
                  #26

                  Allright. I agree. Jets should be accompanied with the kit. Another question. After i fitted the kit. If "the bike" starts with no problems. Should I worry about the idle mixture? Or just keep going? Don't won't it to break down due to a lean idle mixture. Is that even possible?

                  CalumC 1 Reply Last reply
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                  • Irongamer727I Irongamer727

                    Allright. I agree. Jets should be accompanied with the kit. Another question. After i fitted the kit. If "the bike" starts with no problems. Should I worry about the idle mixture? Or just keep going? Don't won't it to break down due to a lean idle mixture. Is that even possible?

                    CalumC Offline
                    CalumC Offline
                    Calum
                    wrote on last edited by
                    #27

                    @irongamer727 If the bike idles happily, and you pulling the throttle doesn't cause hesitance or bog, then the idle mixture is correct. I can't see the idle mixture increasing massively, but definitely should need to be notched up slightly.

                    For the running in period, you shouldn't actually need to up the main jet, as you should be hitting WOT. But I'd rather have it and not need it, than need it and not have it.

                    Always Originate, Never Pirate!

                    Irongamer727I 1 Reply Last reply
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                    • CalumC Calum

                      @irongamer727 If the bike idles happily, and you pulling the throttle doesn't cause hesitance or bog, then the idle mixture is correct. I can't see the idle mixture increasing massively, but definitely should need to be notched up slightly.

                      For the running in period, you shouldn't actually need to up the main jet, as you should be hitting WOT. But I'd rather have it and not need it, than need it and not have it.

                      Irongamer727I Offline
                      Irongamer727I Offline
                      Irongamer727
                      wrote on last edited by
                      #28

                      @calum The bike is running a bit lean with stock pipe so I will definitely change main jet and adjust the needle. Too bad the needle only has 3 positions.

                      CalumC 1 Reply Last reply
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                      • Irongamer727I Irongamer727

                        @calum The bike is running a bit lean with stock pipe so I will definitely change main jet and adjust the needle. Too bad the needle only has 3 positions.

                        CalumC Offline
                        CalumC Offline
                        Calum
                        wrote on last edited by
                        #29

                        @irongamer727 Well needles are readily available.

                        Always Originate, Never Pirate!

                        Irongamer727I 1 Reply Last reply
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                        • CalumC Calum

                          @irongamer727 Well needles are readily available.

                          Irongamer727I Offline
                          Irongamer727I Offline
                          Irongamer727
                          wrote on last edited by
                          #30

                          @calum any recommendations? Stock mikuni 28 dt125x 2005

                          CalumC 1 Reply Last reply
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                          • Irongamer727I Irongamer727

                            @calum any recommendations? Stock mikuni 28 dt125x 2005

                            CalumC Offline
                            CalumC Offline
                            Calum
                            wrote on last edited by
                            #31

                            @irongamer727 Yeah I'd recommend jetting it to suit.

                            I don't run that carb, the only experience I had with the Athena was when my brother ran it on his DTR and he ended up with a vastly too big 38mm Kehin Carb

                            Always Originate, Never Pirate!

                            Irongamer727I 1 Reply Last reply
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                            • CalumC Calum

                              @irongamer727 Yeah I'd recommend jetting it to suit.

                              I don't run that carb, the only experience I had with the Athena was when my brother ran it on his DTR and he ended up with a vastly too big 38mm Kehin Carb

                              Irongamer727I Offline
                              Irongamer727I Offline
                              Irongamer727
                              wrote on last edited by
                              #32

                              @calum so you don't think I need to adjust the needle that much? Rather finding a good jet?

                              CalumC 1 Reply Last reply
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                              • Irongamer727I Irongamer727

                                @calum so you don't think I need to adjust the needle that much? Rather finding a good jet?

                                CalumC Offline
                                CalumC Offline
                                Calum
                                wrote on last edited by
                                #33

                                @irongamer727 As said, it'll definitely need jetting accordingly, but it shouldn't be too far away with what you got.

                                Start with the idle, and work you way to part throttle, then once it's run it, sort out the full throttle.

                                But the stock jet shouldn't lean out the engine when running under part throttle.

                                The needle and pilot jets will affect this IIRC.

                                Always Originate, Never Pirate!

                                Irongamer727I 1 Reply Last reply
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                                • CalumC Calum

                                  @irongamer727 As said, it'll definitely need jetting accordingly, but it shouldn't be too far away with what you got.

                                  Start with the idle, and work you way to part throttle, then once it's run it, sort out the full throttle.

                                  But the stock jet shouldn't lean out the engine when running under part throttle.

                                  The needle and pilot jets will affect this IIRC.

                                  Irongamer727I Offline
                                  Irongamer727I Offline
                                  Irongamer727
                                  wrote on last edited by
                                  #34

                                  @calum thing is. I'm most of the time driving around 1/2 -3/4 throttle. Not using WOT that much. And he is not running perfectly. Bogging a bit around 80 km/h. Definitely not due to an overrich mixture. The plug is, as I mentioned, still a bit too white. Previous owner did probably drill the main jet since it says 75 rather then the stock 210. I have now at my disposal proper Yamaha (mikuni) jets 260-290. Definitely needs new jets. Needle is set in the stock position in the middle.

                                  CalumC 1 Reply Last reply
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                                  • Irongamer727I Irongamer727

                                    @calum thing is. I'm most of the time driving around 1/2 -3/4 throttle. Not using WOT that much. And he is not running perfectly. Bogging a bit around 80 km/h. Definitely not due to an overrich mixture. The plug is, as I mentioned, still a bit too white. Previous owner did probably drill the main jet since it says 75 rather then the stock 210. I have now at my disposal proper Yamaha (mikuni) jets 260-290. Definitely needs new jets. Needle is set in the stock position in the middle.

                                    CalumC Offline
                                    CalumC Offline
                                    Calum
                                    wrote on last edited by
                                    #35

                                    @irongamer727 Drilling jets is a big no no. Never understood that myself.

                                    Yeah I used to get this on my bike lol, always had to blip the throttle a few times to chuck fresh fuel/air into the cylinder.

                                    Always Originate, Never Pirate!

                                    Irongamer727I 1 Reply Last reply
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                                    • CalumC Calum

                                      @irongamer727 Drilling jets is a big no no. Never understood that myself.

                                      Yeah I used to get this on my bike lol, always had to blip the throttle a few times to chuck fresh fuel/air into the cylinder.

                                      Irongamer727I Offline
                                      Irongamer727I Offline
                                      Irongamer727
                                      wrote on last edited by
                                      #36

                                      @calum Annoying as hell. That must be due to the jet right?

                                      CalumC 1 Reply Last reply
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                                      • Irongamer727I Irongamer727

                                        @calum Annoying as hell. That must be due to the jet right?

                                        CalumC Offline
                                        CalumC Offline
                                        Calum
                                        wrote on last edited by
                                        #37

                                        @irongamer727 Ah well, sorry it ran sweet, but my vapor gauge showed a huge spike in temperature lol.

                                        Yeah it sounds like it's not jetted, or something else.

                                        It's all vague and really would need to feel it to understand the probnlem

                                        Always Originate, Never Pirate!

                                        declanD 1 Reply Last reply
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                                        • CalumC Calum

                                          @irongamer727 Ah well, sorry it ran sweet, but my vapor gauge showed a huge spike in temperature lol.

                                          Yeah it sounds like it's not jetted, or something else.

                                          It's all vague and really would need to feel it to understand the probnlem

                                          declanD Offline
                                          declanD Offline
                                          declan
                                          wrote on last edited by
                                          #38

                                          @oldman you know how it is😂😂

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