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Difficult start

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  • CalumC Calum

    @CYBER-NINJA I haven't got a two stroke Oil bottle. There is no parameters for the CDI to not spark if it's low I'm afraid.

    Four things are needed for this to run

    Compression, Ignition, Fuel and oxygen. If it runs and pulls then you've got compression. If the spark plug is wet, then you've got fuel. The only things are suffocated intake system, dirty air filter blocked by leaves and crud. Or the electrical system breaking down. Be it HT leads, Spark Plugs, Pick ups, Coil, weak battery will do it too! CDI could be faulty.

    Way to check electrical is to take the plug out of the head. Rest it against the frame and kick it over. Should see the plug giving off nice and regular sparks.

    Be sure that the correct heat range plug is in there, and that good fuel is used.

    BRE9S BRE8S I believe are the grades you will want.

    NINJAN Offline
    NINJAN Offline
    NINJA
    wrote on last edited by
    #5

    @Calum My reply was based on personal experience, last week I was very low on 2T oil and the bike took like 50 kicks to get it to start. As soon as I topped up the oil it started first time, so I suspected the low oil sensor was stopping the bike from starting? But yeah I agree with your fault diagnosis, you would be surprised how many people have had starting problems with bikes and cars, when it's simply a lack of fluids like oil or petrol, or the immobilizer is not switched off etc.

    SEDUCED BY THE DARK SIDE!!!

    CalumC 1 Reply Last reply
    0
    • NINJAN NINJA

      @Calum My reply was based on personal experience, last week I was very low on 2T oil and the bike took like 50 kicks to get it to start. As soon as I topped up the oil it started first time, so I suspected the low oil sensor was stopping the bike from starting? But yeah I agree with your fault diagnosis, you would be surprised how many people have had starting problems with bikes and cars, when it's simply a lack of fluids like oil or petrol, or the immobilizer is not switched off etc.

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

      @CYBER-NINJA Yeah sure mate I don't doubt that. However there is no mechanism to my knowledge to kill the ignition on low oil. I suspect it was the cool down period from when you stopped kicking it over and filling up yhe oil that was why it started.

      The amount of times in my day I have tried starting my bikes wit the kill switch off is ridiculous lmao! Sometimes things like that just get overlooked.

      Always Originate, Never Pirate!

      1 Reply Last reply
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      • Uber_BelugaU Offline
        Uber_BelugaU Offline
        Uber_Beluga
        wrote on last edited by
        #7

        Same problem thismorning, once again, second attempt at roll starting was succesfull, luckily I roll my bike out to a hill when I leave home!
        Bike got me to my destination and even started first kick after I killed the engine.

        The red engine oil light came on on my way back, I'll wait for things to cool down and check the oil... Logic tells me this is unrelated to my starting problems, but it's a little odd.

        @Calum said in Difficult start:

        Four things are needed for this to run

        Compression, Ignition, Fuel and oxygen. If it runs and pulls then you've got compression. If the spark plug is wet, then you've got fuel. The only things are suffocated intake system, dirty air filter blocked by leaves and crud. Or the electrical system breaking down. Be it HT leads, Spark Plugs, Pick ups, Coil, weak battery will do it too! CDI could be faulty.

        Way to check electrical is to take the plug out of the head. Rest it against the frame and kick it over. Should see the plug giving off nice and regular sparks.

        Be sure that the correct heat range plug is in there, and that good fuel is used.

        BRE9S BRE8S I believe are the grades you will want.

        Thanks for this Calum, very useful! I'll get my tools out and follow this train of thought this weekend. I'll let you know how it goes.

        I'll also just order a new spark plug. This looks about right.
        https://www.amazon.co.uk/Spark-plug-NGK-BR8ES-YAMAHA/dp/B00EK9M87A/ref=sr_1_2?ie=UTF8&qid=1465406511&sr=8-2&keywords=DT+125+re+spark+plug

        -- '02 DT 125 r -- '06 DT125re(Stolen) --

        CalumC 1 Reply Last reply
        0
        • Uber_BelugaU Uber_Beluga

          Same problem thismorning, once again, second attempt at roll starting was succesfull, luckily I roll my bike out to a hill when I leave home!
          Bike got me to my destination and even started first kick after I killed the engine.

          The red engine oil light came on on my way back, I'll wait for things to cool down and check the oil... Logic tells me this is unrelated to my starting problems, but it's a little odd.

          @Calum said in Difficult start:

          Four things are needed for this to run

          Compression, Ignition, Fuel and oxygen. If it runs and pulls then you've got compression. If the spark plug is wet, then you've got fuel. The only things are suffocated intake system, dirty air filter blocked by leaves and crud. Or the electrical system breaking down. Be it HT leads, Spark Plugs, Pick ups, Coil, weak battery will do it too! CDI could be faulty.

          Way to check electrical is to take the plug out of the head. Rest it against the frame and kick it over. Should see the plug giving off nice and regular sparks.

          Be sure that the correct heat range plug is in there, and that good fuel is used.

          BRE9S BRE8S I believe are the grades you will want.

          Thanks for this Calum, very useful! I'll get my tools out and follow this train of thought this weekend. I'll let you know how it goes.

          I'll also just order a new spark plug. This looks about right.
          https://www.amazon.co.uk/Spark-plug-NGK-BR8ES-YAMAHA/dp/B00EK9M87A/ref=sr_1_2?ie=UTF8&qid=1465406511&sr=8-2&keywords=DT+125+re+spark+plug

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

          @Uber_Beluga I personally would get iridium. Just me though

          Always Originate, Never Pirate!

          1 Reply Last reply
          1
          • Uber_BelugaU Offline
            Uber_BelugaU Offline
            Uber_Beluga
            wrote on last edited by Uber_Beluga
            #9

            Like this?: https://www.amazon.co.uk/Spark-plug-NGK-Iridium-BR8EIX/dp/B00ELO18L6/ref=sr_1_5?ie=UTF8&qid=1465406511&sr=8-5&keywords=DT+125+re+spark+plug

            I was going to go for it, but it didn't match the code you gave

            The iridium model is a BR8EIX as opposed to a BR8ES
            Is the same thing in terms of compatability? Presumably the BR8 is the important bit.

            I haven't ordered yet so I can get the iridium one if they're any better.

            EDIT: This explains the NGK plug codes nicely https://www.ngk.de/fileadmin/Dokumente/EN/downloads_not_used_in_download_area/ngk_zuendkerzen_code_en.pdf
            I'll order the iridium model

            -- '02 DT 125 r -- '06 DT125re(Stolen) --

            CalumC 1 Reply Last reply
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            • Uber_BelugaU Uber_Beluga

              Like this?: https://www.amazon.co.uk/Spark-plug-NGK-Iridium-BR8EIX/dp/B00ELO18L6/ref=sr_1_5?ie=UTF8&qid=1465406511&sr=8-5&keywords=DT+125+re+spark+plug

              I was going to go for it, but it didn't match the code you gave

              The iridium model is a BR8EIX as opposed to a BR8ES
              Is the same thing in terms of compatability? Presumably the BR8 is the important bit.

              I haven't ordered yet so I can get the iridium one if they're any better.

              EDIT: This explains the NGK plug codes nicely https://www.ngk.de/fileadmin/Dokumente/EN/downloads_not_used_in_download_area/ngk_zuendkerzen_code_en.pdf
              I'll order the iridium model

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

              @Uber_Beluga That's the pup.

              The 8 and 9 is heat range. A cooler plug will be better to help stop preigniton but a hotter plug may aid starting.

              Something like that anyway,

              Always Originate, Never Pirate!

              NINJAN 1 Reply Last reply
              0
              • BurridgeB Offline
                BurridgeB Offline
                Burridge
                wrote on last edited by
                #11

                Have you tried checking your battery? The fact that it's difficult to start when left for a night or so but easy to start when bumping or after a ride suggests to me Atleast that your batter isn't holding charge all that well. And as said a new plug is always a good first step when having trouble, even if it's sparking fine visibly.

                MightymanM CalumC 2 Replies Last reply
                0
                • BurridgeB Burridge

                  Have you tried checking your battery? The fact that it's difficult to start when left for a night or so but easy to start when bumping or after a ride suggests to me Atleast that your batter isn't holding charge all that well. And as said a new plug is always a good first step when having trouble, even if it's sparking fine visibly.

                  MightymanM Offline
                  MightymanM Offline
                  Mightyman
                  wrote on last edited by
                  #12

                  @Burridge said in Difficult start:

                  Have you tried checking your battery? The fact that it's difficult to start when left for a night or so but easy to start when bumping or after a ride suggests to me Atleast that your batter isn't holding charge all that well. And as said a new plug is always a good first step when having trouble, even if it's sparking fine visibly.

                  Battery wouldn't affect kick starting it.

                  TDR 125 - 2001

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                  • BurridgeB Burridge

                    Have you tried checking your battery? The fact that it's difficult to start when left for a night or so but easy to start when bumping or after a ride suggests to me Atleast that your batter isn't holding charge all that well. And as said a new plug is always a good first step when having trouble, even if it's sparking fine visibly.

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

                    @Burridge I agree weird stuff definitely happens on a low battery, but it should bump no problems.

                    The other ones are if it's dependant on the batter and the fuse is a bit iffy, or the holder at least.

                    Always Originate, Never Pirate!

                    1 Reply Last reply
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                    • CalumC Calum

                      @Uber_Beluga That's the pup.

                      The 8 and 9 is heat range. A cooler plug will be better to help stop preigniton but a hotter plug may aid starting.

                      Something like that anyway,

                      NINJAN Offline
                      NINJAN Offline
                      NINJA
                      wrote on last edited by NINJA
                      #14

                      @Uber_Beluga @Calum My bike came with a BR9ES plug in it, so I just swapped it for a BR9IX this weekend, thinking I was just swapping from a regular plug to an Iridium one. But boy have I noticed the difference! She pulls like an express train now and my previous best top speed was 72MPH, now I can get 78MPH. She still starts first kick 99.9% of the time and climbs up the rev range a lot faster, There is a bit more vibration coming through, so I'm guessing that the iridium part makes for a better spark? AKA a bigger bang, I hope that I'm not gonna do any long term damage??? ;O)

                      SEDUCED BY THE DARK SIDE!!!

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                      • Uber_BelugaU Offline
                        Uber_BelugaU Offline
                        Uber_Beluga
                        wrote on last edited by Uber_Beluga
                        #15

                        @Calum
                        8 seems to be recommended heat range for my particular bike, I see it's 9 on some other DTs, seems strange that they would vary.
                        I've just ordered one of each heat range so I can try them out. I found them for around 10 pounds each (here and here) so relatively inexpensive in the grand scheme of things.
                        A quick google of preignition has me kind of scared of the 9. Even with the tempting attraction of making starting easier I think I'll avoid putting the 9 in if I can.

                        @Burridge
                        I'll give the battery a check anyway as I have a multimeter, I don't have a working starter motor in the bike at the moment (It's an RE model), but I'm hoping to pick one up when one appears on Ebay so might as well get a new battery if mine is no good.

                        EDIT: Just realised the higher the number for the heat range the cooler the plug, I guess I have nothing to worry about with either plug then, worst case scenario it just wont start.

                        -- '02 DT 125 r -- '06 DT125re(Stolen) --

                        1 Reply Last reply
                        1
                        • CalumC Offline
                          CalumC Offline
                          Calum
                          wrote on last edited by
                          #16

                          Yeah I ran both, preignition is only going to really be an issue if you're getting into the tuning game. I'm sure those will be fine

                          Always Originate, Never Pirate!

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                          • Uber_BelugaU Offline
                            Uber_BelugaU Offline
                            Uber_Beluga
                            wrote on last edited by
                            #17

                            I think I made a little progress with the starting problem today.

                            I can confirm that there is no spark from the plug when kick-starting. Any ideas what could be causing no spark? The bike does run when I get it started by roll starting it, so it must spark sometimes.

                            I'll have another go next weekend, but any advice on where to start in advance would be appreciated 🙂

                            -- '02 DT 125 r -- '06 DT125re(Stolen) --

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                            • Uber_BelugaU Offline
                              Uber_BelugaU Offline
                              Uber_Beluga
                              wrote on last edited by
                              #18

                              I've spent more time on the no spark issue today. Got the new battery in and no change, that didn't really surprise me, but I wanted a new battery anyway given that the old one was only giving around 12.3v on a full charge.

                              I started going down a list of things to check that I found from this random video on YouTube. (Internet is my only source of knowledge)
                              https://www.youtube.com/watch?v=wjvnUIwQ33Y

                              First I checked my kill switch, it wasn't good. Full resistance switched on or off. If I caress the switch in just the right way, sometimes it works, but I'd rather not carry my multimetre with me everywhere I go, so off it goes.
                              They aren't cheap, so I'm probably going to try and fix the switch, simple enough electrics hopefully.

                              Now, question is, should I get a spark with that kill switch pulled from the bike, or will I need to bridge the connections that it plugged into? I didn't try that when I was outside, but thinking retrospectively that's probably what I should have done?

                              I went on to check the coil which caused more confusion, but I won't get into that until I've got the switch sorted.

                              -- '02 DT 125 r -- '06 DT125re(Stolen) --

                              CalumC 1 Reply Last reply
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                              • Uber_BelugaU Uber_Beluga

                                I've spent more time on the no spark issue today. Got the new battery in and no change, that didn't really surprise me, but I wanted a new battery anyway given that the old one was only giving around 12.3v on a full charge.

                                I started going down a list of things to check that I found from this random video on YouTube. (Internet is my only source of knowledge)
                                https://www.youtube.com/watch?v=wjvnUIwQ33Y

                                First I checked my kill switch, it wasn't good. Full resistance switched on or off. If I caress the switch in just the right way, sometimes it works, but I'd rather not carry my multimetre with me everywhere I go, so off it goes.
                                They aren't cheap, so I'm probably going to try and fix the switch, simple enough electrics hopefully.

                                Now, question is, should I get a spark with that kill switch pulled from the bike, or will I need to bridge the connections that it plugged into? I didn't try that when I was outside, but thinking retrospectively that's probably what I should have done?

                                I went on to check the coil which caused more confusion, but I won't get into that until I've got the switch sorted.

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

                                @Uber_Beluga Bridge the connection.

                                The kill switch contacts have probably corroded. Try spray some electrical contact cleaner in there. Or dismantle it and rub the switch contcts down,

                                Always Originate, Never Pirate!

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                                • Uber_BelugaU Offline
                                  Uber_BelugaU Offline
                                  Uber_Beluga
                                  wrote on last edited by
                                  #20

                                  Thanks Calum,

                                  I'll get the switch sorted through the week and have it ready for next weeked to try again.

                                  I spent about an hour trying to get a spark with that switch off the bike without even thinking that having it off was the same as having it not working. Feeling pretty thick right now.

                                  -- '02 DT 125 r -- '06 DT125re(Stolen) --

                                  CalumC R 2 Replies Last reply
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                                  • Uber_BelugaU Uber_Beluga

                                    Thanks Calum,

                                    I'll get the switch sorted through the week and have it ready for next weeked to try again.

                                    I spent about an hour trying to get a spark with that switch off the bike without even thinking that having it off was the same as having it not working. Feeling pretty thick right now.

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

                                    @Uber_Beluga Not really

                                    We've all been there. Live and learn.

                                    Tobe fair, on my brothers DT, something was properly merssed up. You could only get a spark if you kicked the bike over, and turned the ignition on at the same time. I kid you not. Never got to the bottom of it.

                                    Of course this was some time ago now.

                                    Always Originate, Never Pirate!

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                                    • Uber_BelugaU Uber_Beluga

                                      Thanks Calum,

                                      I'll get the switch sorted through the week and have it ready for next weeked to try again.

                                      I spent about an hour trying to get a spark with that switch off the bike without even thinking that having it off was the same as having it not working. Feeling pretty thick right now.

                                      R Offline
                                      R Offline
                                      Raydt
                                      wrote on last edited by
                                      #22

                                      @Uber_Beluga
                                      How many wires going up to the kill switch, usually only one and when the switch is closed it earth's out the low voltage side of the coil, so if it is disconnected and taped up it should not stop it from starting.

                                      1 Reply Last reply
                                      1
                                      • Uber_BelugaU Offline
                                        Uber_BelugaU Offline
                                        Uber_Beluga
                                        wrote on last edited by Uber_Beluga
                                        #23

                                        4 wires, same connection as the starter button

                                        From what I can tell, both the button and the switch produce infinate resistance when they're in their "off" position, but very little to no resistance when in the "on" position. The kill switch doesn't always go into the "on" posisiton so easy. (hence it's removal)

                                        I don't think it's as you describe on my bike (06 RE), but hey, I could definately be wrong. I'm pretty lost with electronics.

                                        -- '02 DT 125 r -- '06 DT125re(Stolen) --

                                        CalumC R 2 Replies Last reply
                                        0
                                        • Uber_BelugaU Uber_Beluga

                                          4 wires, same connection as the starter button

                                          From what I can tell, both the button and the switch produce infinate resistance when they're in their "off" position, but very little to no resistance when in the "on" position. The kill switch doesn't always go into the "on" posisiton so easy. (hence it's removal)

                                          I don't think it's as you describe on my bike (06 RE), but hey, I could definately be wrong. I'm pretty lost with electronics.

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

                                          @Uber_Beluga Infinite resistance?

                                          Surely just an on off switch would cause infinite resistance since it is very difficult for Electricity to bridge the gap.

                                          Always Originate, Never Pirate!

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