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Trying to fix an issue

Scheduled Pinned Locked Moved Carburetor
jettingair screw
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  • S SpookDog

    @Stevie-Wonder

    The power valve is open at default any was. It’s only when you start the bike that it ‘closes’...
    You could pull the plug before starting the engine...

    You do have the power valve set at open/flush when the engine is off don’t you?...

    Stevie WonderS Offline
    Stevie WonderS Offline
    Stevie Wonder
    wrote on last edited by
    #34

    @SpookDog said in Trying to fix an issue:

    @Stevie-Wonder

    The power valve is open at default any was. It’s only when you start the bike that it ‘closes’...
    You could pull the plug before starting the engine...

    You do have the power valve set at open/flush when the engine is off don’t you?...

    Yep, admittedly I haven’t checked but I doubt it’s just magically jumped out of place since I last set it 😂

    S 1 Reply Last reply
    0
    • Stevie WonderS Stevie Wonder

      @SpookDog said in Trying to fix an issue:

      @Stevie-Wonder

      The power valve is open at default any was. It’s only when you start the bike that it ‘closes’...
      You could pull the plug before starting the engine...

      You do have the power valve set at open/flush when the engine is off don’t you?...

      Yep, admittedly I haven’t checked but I doubt it’s just magically jumped out of place since I last set it 😂

      S Offline
      S Offline
      SpookDog
      wrote on last edited by
      #35

      @Stevie-Wonder

      How long have you been having this problem? Hasn’t been since you last set up the power valve has it 😁

      Stevie WonderS 1 Reply Last reply
      0
      • S SpookDog

        @Stevie-Wonder

        How long have you been having this problem? Hasn’t been since you last set up the power valve has it 😁

        Stevie WonderS Offline
        Stevie WonderS Offline
        Stevie Wonder
        wrote on last edited by
        #36

        Since the first or second time I took my carb off to inspect the float valve when fuel was pissing out the overflow

        I just took the bike out and I’m certain the powervalve is operating as should be and sat in the right place.

        I do however have a sneaky feeling the air boot isn’t properly sealed, causing an air leak.

        I’ve also found a little pin prick hole in the carb warmer hose that sends coolant into the carb.

        I took the bike out for a little ride, I say little because I got less then ten minutes ago and the temp gauge was already 3/4 across the dash and climbing.

        There where a couple times where the bike just shot off like a rocket whilst the valve was pinned but other then that It’d get to about 6-8k (at a guess because remember I don’t have working clocks) then struggle to go any further.

        S 1 Reply Last reply
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        • Stevie WonderS Stevie Wonder

          Since the first or second time I took my carb off to inspect the float valve when fuel was pissing out the overflow

          I just took the bike out and I’m certain the powervalve is operating as should be and sat in the right place.

          I do however have a sneaky feeling the air boot isn’t properly sealed, causing an air leak.

          I’ve also found a little pin prick hole in the carb warmer hose that sends coolant into the carb.

          I took the bike out for a little ride, I say little because I got less then ten minutes ago and the temp gauge was already 3/4 across the dash and climbing.

          There where a couple times where the bike just shot off like a rocket whilst the valve was pinned but other then that It’d get to about 6-8k (at a guess because remember I don’t have working clocks) then struggle to go any further.

          S Offline
          S Offline
          SpookDog
          wrote on last edited by
          #37

          @Stevie-Wonder

          Did you ever fix the leaky crank seal on the flywheel side, bud? Something still ain’t right if you’re getting that hot. I used to have temp troubles till I sorted out my jetting. Even my bike has been running cool during the worst of the heatwaves. While there is water in the radiator anyways 🙂

          I’d be looking for any air leaks. Spray on either wd40 or (I use) solvent brake/clutch/carb cleaner. The revs will lower/settle down if it temporarily blocks an air leak...

          Stevie WonderS 1 Reply Last reply
          1
          • S SpookDog

            @Stevie-Wonder

            Did you ever fix the leaky crank seal on the flywheel side, bud? Something still ain’t right if you’re getting that hot. I used to have temp troubles till I sorted out my jetting. Even my bike has been running cool during the worst of the heatwaves. While there is water in the radiator anyways 🙂

            I’d be looking for any air leaks. Spray on either wd40 or (I use) solvent brake/clutch/carb cleaner. The revs will lower/settle down if it temporarily blocks an air leak...

            Stevie WonderS Offline
            Stevie WonderS Offline
            Stevie Wonder
            wrote on last edited by
            #38

            @SpookDog said in Trying to fix an issue:

            @Stevie-Wonder

            Did you ever fix the leaky crank seal on the flywheel side, bud? Something still ain’t right if you’re getting that hot. I used to have temp troubles till I sorted out my jetting. Even my bike has been running cool during the worst of the heatwaves. While there is water in the radiator anyways 🙂

            I’d be looking for any air leaks. Spray on either wd40 or (I use) solvent brake/clutch/carb cleaner. The revs will lower/settle down if it temporarily blocks an air leak...

            Nope, turned out there was no crank seal. The bike held and made good compression when I did a compression check.

            To back this up when I crashed my bike the issue magically resolved itself and the bike suddenly ran beautifully, as good if not better then the day I got it.

            S 1 Reply Last reply
            0
            • Stevie WonderS Stevie Wonder

              @SpookDog said in Trying to fix an issue:

              @Stevie-Wonder

              Did you ever fix the leaky crank seal on the flywheel side, bud? Something still ain’t right if you’re getting that hot. I used to have temp troubles till I sorted out my jetting. Even my bike has been running cool during the worst of the heatwaves. While there is water in the radiator anyways 🙂

              I’d be looking for any air leaks. Spray on either wd40 or (I use) solvent brake/clutch/carb cleaner. The revs will lower/settle down if it temporarily blocks an air leak...

              Nope, turned out there was no crank seal. The bike held and made good compression when I did a compression check.

              To back this up when I crashed my bike the issue magically resolved itself and the bike suddenly ran beautifully, as good if not better then the day I got it.

              S Offline
              S Offline
              SpookDog
              wrote on last edited by SpookDog
              #39

              @Stevie-Wonder

              The crank seal failing wouldn’t affect bore pressure. That’s purely between the piston&rings and the head. It would totally fuck with your mixture & running though. It’s such a cheap and easy fix it’d be silly to ignore it. I seem to remember you saying the revs settled down when you sprayed it before?...

              Stevie WonderS 1 Reply Last reply
              1
              • S SpookDog

                @Stevie-Wonder

                The crank seal failing wouldn’t affect bore pressure. That’s purely between the piston&rings and the head. It would totally fuck with your mixture & running though. It’s such a cheap and easy fix it’d be silly to ignore it. I seem to remember you saying the revs settled down when you sprayed it before?...

                Stevie WonderS Offline
                Stevie WonderS Offline
                Stevie Wonder
                wrote on last edited by
                #40

                @SpookDog said in Trying to fix an issue:

                @Stevie-Wonder

                The crank seal failing wouldn’t affect bore pressure. That’s purely between the piston&rings and the head. It would totally fuck with your mixture & running though. It’s such a cheap and easy fix it’d be silly to ignore it. I seem to remember you saying the revs settled down when you sprayed it before?...

                Nah, I sprayed a couple different flammable substances and it made no difference.

                And ahh okay

                S 1 Reply Last reply
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                • Stevie WonderS Stevie Wonder

                  @SpookDog said in Trying to fix an issue:

                  @Stevie-Wonder

                  The crank seal failing wouldn’t affect bore pressure. That’s purely between the piston&rings and the head. It would totally fuck with your mixture & running though. It’s such a cheap and easy fix it’d be silly to ignore it. I seem to remember you saying the revs settled down when you sprayed it before?...

                  Nah, I sprayed a couple different flammable substances and it made no difference.

                  And ahh okay

                  S Offline
                  S Offline
                  SpookDog
                  wrote on last edited by
                  #41

                  @Stevie-Wonder
                  My bad, no worries 🙂 ...

                  Stevie WonderS 1 Reply Last reply
                  0
                  • S SpookDog

                    @Stevie-Wonder
                    My bad, no worries 🙂 ...

                    Stevie WonderS Offline
                    Stevie WonderS Offline
                    Stevie Wonder
                    wrote on last edited by Stevie Wonder
                    #42

                    @SpookDog
                    No worries man, I wish it was that, it’d be an easy fix then. But the fact the issue solved itself and ran perfect for a good month after I thought it was that rules out LH crank seal being the problem entirely

                    It’s worth noting I tried the old trick of running the bike with the choke on to richen things thinking this might cause stop the heat building and possibly make a difference to how the bike was running.
                    Unfortunately though this made no difference, temp still carried on soaring and still reluctant to go through the revs

                    The only place there could be an air leak is where the rubber boot joins the air box… this would then cause a lean running engine.
                    This leaves me some questions though…
                    I’m led to believe where the air boot meets the air box doesn’t have to be an air tight unit, is this right?

                    Being a water cooled engine doesn’t this mean as long as there’s sufficient coolant, your radiator and water pump hoses etc are all in good working then even if you had an engine that was run very very lean the heat would be managed?

                    Or would it be more a case that the cooling system isn’t up to the job to handle those conditions?

                    As it stands to sort this I have to

                    • Check there’s enough coolant (I can’t imagine having lost enough to make a difference however the carb warmer pipes are still prone to odd drip or two even when I plugged them so this could have built up over time, always worth checking).
                    • Check water pump is working
                    • take zorst off and fit new carb warmer coolant line (as one has a pin prick hole from being nipped by the hose clamp)
                    S markus.wM 2 Replies Last reply
                    0
                    • Stevie WonderS Stevie Wonder

                      @SpookDog
                      No worries man, I wish it was that, it’d be an easy fix then. But the fact the issue solved itself and ran perfect for a good month after I thought it was that rules out LH crank seal being the problem entirely

                      It’s worth noting I tried the old trick of running the bike with the choke on to richen things thinking this might cause stop the heat building and possibly make a difference to how the bike was running.
                      Unfortunately though this made no difference, temp still carried on soaring and still reluctant to go through the revs

                      The only place there could be an air leak is where the rubber boot joins the air box… this would then cause a lean running engine.
                      This leaves me some questions though…
                      I’m led to believe where the air boot meets the air box doesn’t have to be an air tight unit, is this right?

                      Being a water cooled engine doesn’t this mean as long as there’s sufficient coolant, your radiator and water pump hoses etc are all in good working then even if you had an engine that was run very very lean the heat would be managed?

                      Or would it be more a case that the cooling system isn’t up to the job to handle those conditions?

                      As it stands to sort this I have to

                      • Check there’s enough coolant (I can’t imagine having lost enough to make a difference however the carb warmer pipes are still prone to odd drip or two even when I plugged them so this could have built up over time, always worth checking).
                      • Check water pump is working
                      • take zorst off and fit new carb warmer coolant line (as one has a pin prick hole from being nipped by the hose clamp)
                      S Offline
                      S Offline
                      SpookDog
                      wrote on last edited by
                      #43

                      @Stevie-Wonder

                      Have you not checked the radiator level yet? I would check that first job. Second would be swapping out the thermostat. Running lean made my bike run ‘hotter’ but not that hot!
                      Also check for overflowed coolant at the expansion tank filler. Sticky crap below it on the chain guard and swing arm...

                      Stevie WonderS 1 Reply Last reply
                      0
                      • CalumC Offline
                        CalumC Offline
                        Calum
                        wrote on last edited by
                        #44

                        @Stevie-Wonder Air leaks before the carburettor are generally not an issue since you have a carburettor. By that I mean, the venturi effect created due to the air meters the fueling. Since you're only running at normal atmospheric pressures you can rule this out.

                        With regards to coolant and engine temp, if it's running so lean that the engine detonates then the temperature will spike before/during it seizes. By the time the temperature moves it'll already been too late. You have to keep an ear out for detonation in that case.

                        Always Originate, Never Pirate!

                        markus.wM 1 Reply Last reply
                        0
                        • Stevie WonderS Stevie Wonder

                          @SpookDog
                          No worries man, I wish it was that, it’d be an easy fix then. But the fact the issue solved itself and ran perfect for a good month after I thought it was that rules out LH crank seal being the problem entirely

                          It’s worth noting I tried the old trick of running the bike with the choke on to richen things thinking this might cause stop the heat building and possibly make a difference to how the bike was running.
                          Unfortunately though this made no difference, temp still carried on soaring and still reluctant to go through the revs

                          The only place there could be an air leak is where the rubber boot joins the air box… this would then cause a lean running engine.
                          This leaves me some questions though…
                          I’m led to believe where the air boot meets the air box doesn’t have to be an air tight unit, is this right?

                          Being a water cooled engine doesn’t this mean as long as there’s sufficient coolant, your radiator and water pump hoses etc are all in good working then even if you had an engine that was run very very lean the heat would be managed?

                          Or would it be more a case that the cooling system isn’t up to the job to handle those conditions?

                          As it stands to sort this I have to

                          • Check there’s enough coolant (I can’t imagine having lost enough to make a difference however the carb warmer pipes are still prone to odd drip or two even when I plugged them so this could have built up over time, always worth checking).
                          • Check water pump is working
                          • take zorst off and fit new carb warmer coolant line (as one has a pin prick hole from being nipped by the hose clamp)
                          markus.wM Offline
                          markus.wM Offline
                          markus.w
                          wrote on last edited by
                          #45

                          @Stevie-Wonder a lean condition seriously affects the temperature. A main jet 1 or 2 sizes too small can easily make a difference of 20 degrees so an air leak caused by a split rubber can be catastrophic.

                          1 Reply Last reply
                          0
                          • CalumC Calum

                            @Stevie-Wonder Air leaks before the carburettor are generally not an issue since you have a carburettor. By that I mean, the venturi effect created due to the air meters the fueling. Since you're only running at normal atmospheric pressures you can rule this out.

                            With regards to coolant and engine temp, if it's running so lean that the engine detonates then the temperature will spike before/during it seizes. By the time the temperature moves it'll already been too late. You have to keep an ear out for detonation in that case.

                            markus.wM Offline
                            markus.wM Offline
                            markus.w
                            wrote on last edited by
                            #46

                            @Calum ah yes, before the carb won't make much difference. My airbox is deleted and have a ram air pod filter. Just up couple of sizes on the jets. Some people run no air filter.

                            1 Reply Last reply
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                            • Stevie WonderS Offline
                              Stevie WonderS Offline
                              Stevie Wonder
                              wrote on last edited by Stevie Wonder
                              #47

                              Okay wicked, so we can rule out the rubber boot to the air box not being airtight as not being an issue.

                              Also the jetting in the carb is the exact same as it’s always been since I’ve had it so jetting shouldn’t be an issue, the only thing that could’ve changed slightly is the air screw.

                              I’ll keep an ear out for detonation as that’ll give an indicator to wether it’s the engine running lean being the problem or it just being a cooling problem.

                              S 1 Reply Last reply
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                              • Stevie WonderS Stevie Wonder

                                Okay wicked, so we can rule out the rubber boot to the air box not being airtight as not being an issue.

                                Also the jetting in the carb is the exact same as it’s always been since I’ve had it so jetting shouldn’t be an issue, the only thing that could’ve changed slightly is the air screw.

                                I’ll keep an ear out for detonation as that’ll give an indicator to wether it’s the engine running lean being the problem or it just being a cooling problem.

                                S Offline
                                S Offline
                                SpookDog
                                wrote on last edited by
                                #48

                                @Stevie-Wonder
                                Did you check the radiator coolant level?...

                                Stevie WonderS 1 Reply Last reply
                                0
                                • S SpookDog

                                  @Stevie-Wonder
                                  Did you check the radiator coolant level?...

                                  Stevie WonderS Offline
                                  Stevie WonderS Offline
                                  Stevie Wonder
                                  wrote on last edited by
                                  #49

                                  @SpookDog said in Trying to fix an issue:

                                  @Stevie-Wonder
                                  Did you check the radiator coolant level?...

                                  Nah after I took it for a ride I just put it back and haven’t touched it since.

                                  Been saying to myself I’d do a little bit here and there after work but this heat has been killing me off and leaving me so fucked where the only thing left to do is have a beer and chill out.

                                  However today I’m going to go through that checklist today and try do as much as I can.

                                  CalumC 1 Reply Last reply
                                  0
                                  • Stevie WonderS Stevie Wonder

                                    @SpookDog said in Trying to fix an issue:

                                    @Stevie-Wonder
                                    Did you check the radiator coolant level?...

                                    Nah after I took it for a ride I just put it back and haven’t touched it since.

                                    Been saying to myself I’d do a little bit here and there after work but this heat has been killing me off and leaving me so fucked where the only thing left to do is have a beer and chill out.

                                    However today I’m going to go through that checklist today and try do as much as I can.

                                    CalumC Offline
                                    CalumC Offline
                                    Calum
                                    wrote on last edited by
                                    #50

                                    @Stevie-Wonder Ptsch! What sort of attitude is that! This is perfect trail riding weather. You're young, you should be full of energy smashing it out.

                                    Always Originate, Never Pirate!

                                    1 Reply Last reply
                                    0
                                    • S SpookDog

                                      @Stevie-Wonder

                                      Have you not checked the radiator level yet? I would check that first job. Second would be swapping out the thermostat. Running lean made my bike run ‘hotter’ but not that hot!
                                      Also check for overflowed coolant at the expansion tank filler. Sticky crap below it on the chain guard and swing arm...

                                      Stevie WonderS Offline
                                      Stevie WonderS Offline
                                      Stevie Wonder
                                      wrote on last edited by Stevie Wonder
                                      #51

                                      @SpookDog said in Trying to fix an issue:

                                      @Stevie-Wonder

                                      Have you not checked the radiator level yet? I would check that first job. Second would be swapping out the thermostat. Running lean made my bike run ‘hotter’ but not that hot!
                                      Also check for overflowed coolant at the expansion tank filler. Sticky crap below it on the chain guard and swing arm...

                                      No overflowed coolant. I do have a spare thermostat off a 4FU head I could try too.

                                      @Calum dont remind me 😂 10 hour shifts grafting in 30 degree heat does a number on you though 😂

                                      S 1 Reply Last reply
                                      0
                                      • Stevie WonderS Stevie Wonder

                                        @SpookDog said in Trying to fix an issue:

                                        @Stevie-Wonder

                                        Have you not checked the radiator level yet? I would check that first job. Second would be swapping out the thermostat. Running lean made my bike run ‘hotter’ but not that hot!
                                        Also check for overflowed coolant at the expansion tank filler. Sticky crap below it on the chain guard and swing arm...

                                        No overflowed coolant. I do have a spare thermostat off a 4FU head I could try too.

                                        @Calum dont remind me 😂 10 hour shifts grafting in 30 degree heat does a number on you though 😂

                                        S Offline
                                        S Offline
                                        SpookDog
                                        wrote on last edited by
                                        #52

                                        @Stevie-Wonder

                                        And the radiator is full too? If it is then it’s definitely worth trying another thermostat. I don’t even know how many I’ve got in my collection anymore! I brought an old style glass thermometer to check opening temps accurately (only a few £), also to tell me what position on the temp gauge was what, instead of lucky dip! 😜

                                        1 Reply Last reply
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                                        • Stevie WonderS Offline
                                          Stevie WonderS Offline
                                          Stevie Wonder
                                          wrote on last edited by
                                          #53

                                          Radiator wasn’t full, I have since topped up with roughly half a bottle of putoline coolant.

                                          I’d left to tick over for 10 minutes and didn’t have any anomaly with temp. Gonna take her for a test ride soon. I am hopeful that’s solved it though.

                                          I have noticed a noise that sounds a lot like a bearing of some sort gone in the top end. At first I thought it was just because I had the powervalve cover open that there was more of a raw noise but when you listen I definitely doesn’t sound right

                                          link text

                                          Failing that if a bearings gone that’ll explain a lot!

                                          HOTSHOT IIIH S 2 Replies Last reply
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