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Trying to fix an issue

Scheduled Pinned Locked Moved Carburetor
jettingair screw
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  • 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.

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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
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          • 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
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            • 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
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              • 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
                  0
                  • Stevie WonderS Stevie Wonder

                    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 Offline
                    HOTSHOT IIIH Offline
                    HOTSHOT III
                    wrote on last edited by HOTSHOT III
                    #54

                    @Stevie-Wonder Just watched/listened to your vid. Difficult to diagnose just by listening but I'd say that could necessitate a stripdown to find the cause.

                    Beforehand though you might want to take a look at the R/H powervalve cover behind the expansion chamber as these have a habit of breaking around the retaining bolt and rattling due to exhaust pressure and the broken bit stopping it falling out completely.

                    It happened to me once on an RD500LC (it uses the same part x 4) and it made that exact noise. Everyone I was riding with ripped the p!$s out of me because we all thought it had blown up but I rode it 50 miles to get home and just replaced it. Hope that's all it is!

                    1 Reply Last reply
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                    • Stevie WonderS Stevie Wonder

                      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!

                      S Offline
                      S Offline
                      SpookDog
                      wrote on last edited by
                      #55

                      @Stevie-Wonder

                      I think your head gasket may be blown. If you can’t find a leak in the radiator or hoses. Check the level of fluid in the expansion tank. If it’s full to the brim it’s a red flag for the head gasket...

                      Keep an eye on the temp gauge when riding and check the radiator level after...
                      Good luck bud!...

                      1 Reply Last reply
                      1
                      • Stevie WonderS Offline
                        Stevie WonderS Offline
                        Stevie Wonder
                        wrote on last edited by
                        #56

                        Took the bike for a spin!

                        Good news the cooling issue was nothing more then being short of coolant. What I thought wasn’t a lot ended up being roughly half to three quarters a bottle of putoline coolant that got swallowed up before hitting the full limit in the rad.

                        Coolant issue now fixed!

                        I’ve not had a drop of fuel come out the overflow either, woo!

                        The addition of a reliable working petcock is a bonus too.

                        I’ve readjusted the PV so it’s no longer perfectly flush with the exhaust port but align with the hole in the pulley.

                        This has proven to work a lot better in combination with the OEM pipe I’m running. Torque for days.
                        The shut off point powerband/power wise is 10.5k with no overrev,
                        the exhaust port not opening further I’m pretty sure would prevent this anyway however if say for example you where running a ported setup or something like a dep pipe known for its over-rev capabilities then you’d definitely want your exhaust perfectly flush.

                        I enjoy my ride a lot. I actually couldn’t got off the bike and struggled to turn around to go home. So much so I ended up running out of petrol and having to walk 3 miles to the petrol station with a dead phone. 😂

                        This brings me to the next thing, my bike actually sometimes to run alright suddenly?

                        Every now and again she’s hesitant to pull through or you’ll be WOT in band and then it’ll cut out then come back on again

                        I’m also finding you have to roll on the throttle with the Rev’s and that it seems to like going through higher gears more but other then that alright?

                        S HOTSHOT IIIH 2 Replies Last reply
                        0
                        • Stevie WonderS Stevie Wonder

                          Took the bike for a spin!

                          Good news the cooling issue was nothing more then being short of coolant. What I thought wasn’t a lot ended up being roughly half to three quarters a bottle of putoline coolant that got swallowed up before hitting the full limit in the rad.

                          Coolant issue now fixed!

                          I’ve not had a drop of fuel come out the overflow either, woo!

                          The addition of a reliable working petcock is a bonus too.

                          I’ve readjusted the PV so it’s no longer perfectly flush with the exhaust port but align with the hole in the pulley.

                          This has proven to work a lot better in combination with the OEM pipe I’m running. Torque for days.
                          The shut off point powerband/power wise is 10.5k with no overrev,
                          the exhaust port not opening further I’m pretty sure would prevent this anyway however if say for example you where running a ported setup or something like a dep pipe known for its over-rev capabilities then you’d definitely want your exhaust perfectly flush.

                          I enjoy my ride a lot. I actually couldn’t got off the bike and struggled to turn around to go home. So much so I ended up running out of petrol and having to walk 3 miles to the petrol station with a dead phone. 😂

                          This brings me to the next thing, my bike actually sometimes to run alright suddenly?

                          Every now and again she’s hesitant to pull through or you’ll be WOT in band and then it’ll cut out then come back on again

                          I’m also finding you have to roll on the throttle with the Rev’s and that it seems to like going through higher gears more but other then that alright?

                          S Offline
                          S Offline
                          SpookDog
                          wrote on last edited by
                          #57

                          @Stevie-Wonder

                          Did you check the coolant expansion tank? That coolant has to have gone somewhere!
                          Keep an eye on the temp gauge and radiator level, please bud...

                          1 Reply Last reply
                          0
                          • Stevie WonderS Stevie Wonder

                            Took the bike for a spin!

                            Good news the cooling issue was nothing more then being short of coolant. What I thought wasn’t a lot ended up being roughly half to three quarters a bottle of putoline coolant that got swallowed up before hitting the full limit in the rad.

                            Coolant issue now fixed!

                            I’ve not had a drop of fuel come out the overflow either, woo!

                            The addition of a reliable working petcock is a bonus too.

                            I’ve readjusted the PV so it’s no longer perfectly flush with the exhaust port but align with the hole in the pulley.

                            This has proven to work a lot better in combination with the OEM pipe I’m running. Torque for days.
                            The shut off point powerband/power wise is 10.5k with no overrev,
                            the exhaust port not opening further I’m pretty sure would prevent this anyway however if say for example you where running a ported setup or something like a dep pipe known for its over-rev capabilities then you’d definitely want your exhaust perfectly flush.

                            I enjoy my ride a lot. I actually couldn’t got off the bike and struggled to turn around to go home. So much so I ended up running out of petrol and having to walk 3 miles to the petrol station with a dead phone. 😂

                            This brings me to the next thing, my bike actually sometimes to run alright suddenly?

                            Every now and again she’s hesitant to pull through or you’ll be WOT in band and then it’ll cut out then come back on again

                            I’m also finding you have to roll on the throttle with the Rev’s and that it seems to like going through higher gears more but other then that alright?

                            HOTSHOT IIIH Offline
                            HOTSHOT IIIH Offline
                            HOTSHOT III
                            wrote on last edited by
                            #58

                            @Stevie-Wonder said in Trying to fix an issue:

                            This brings me to the next thing, my bike actually sometimes to run alright suddenly?

                            Every now and again she’s hesitant to pull through or you’ll be WOT in band and then it’ll cut out then come back on again

                            I’m also finding you have to roll on the throttle with the Rev’s and that it seems to like going through higher gears more but other then that alright?

                            The cutting out at high revs does sound like it could be your HT lead starting to deteriorate, when that happened to me it manifested itself as a high-rpm (9k +) misfire. Not much fun when overtaking etc.

                            Made a huge difference when I soldered a new one to the coil output, the job took about an hour so the bike was no longer at operating temperature when I tested it but the front wheel came up as I pulled out of the driveway! 1992 but I'll never forget how it transformed the bike.

                            If I can dig out a loose coil and some lead I'll do a forum post with pictures 👍

                            Stevie WonderS 1 Reply Last reply
                            1
                            • HOTSHOT IIIH HOTSHOT III

                              @Stevie-Wonder said in Trying to fix an issue:

                              This brings me to the next thing, my bike actually sometimes to run alright suddenly?

                              Every now and again she’s hesitant to pull through or you’ll be WOT in band and then it’ll cut out then come back on again

                              I’m also finding you have to roll on the throttle with the Rev’s and that it seems to like going through higher gears more but other then that alright?

                              The cutting out at high revs does sound like it could be your HT lead starting to deteriorate, when that happened to me it manifested itself as a high-rpm (9k +) misfire. Not much fun when overtaking etc.

                              Made a huge difference when I soldered a new one to the coil output, the job took about an hour so the bike was no longer at operating temperature when I tested it but the front wheel came up as I pulled out of the driveway! 1992 but I'll never forget how it transformed the bike.

                              If I can dig out a loose coil and some lead I'll do a forum post with pictures 👍

                              Stevie WonderS Offline
                              Stevie WonderS Offline
                              Stevie Wonder
                              wrote on last edited by
                              #59

                              @HOTSHOT-III what you described is exactly what I’m experiencing.

                              New racey red NGK HT lead will be getting ordered Friday.
                              I’ve always wanted one but didn’t actually think they made a difference other then cool points

                              1 Reply Last reply
                              1
                              • CalumC Offline
                                CalumC Offline
                                Calum
                                wrote on last edited by
                                #60

                                Whatever you do, DO NOT and I mean DO NOT buy those shitty fucking Chinese "Racing Coils". Go Genuine or Go Home!

                                Always Originate, Never Pirate!

                                Stevie WonderS 1 Reply Last reply
                                2
                                • CalumC Calum

                                  Whatever you do, DO NOT and I mean DO NOT buy those shitty fucking Chinese "Racing Coils". Go Genuine or Go Home!

                                  Stevie WonderS Offline
                                  Stevie WonderS Offline
                                  Stevie Wonder
                                  wrote on last edited by
                                  #61

                                  @Calum said in Trying to fix an issue:

                                  Whatever you do, DO NOT and I mean DO NOT buy those shitty fucking Chinese "Racing Coils". Go Genuine or Go Home!

                                  Oh fuck no! 🤮

                                  Racing CDI’s used to be all the rage when I was tuning my lexmoto a few years back that was until everyone cottoned on the fact it turns a bike with a perfectly good hardline ignition and then removes the limiter all together so the bike could Rev so high the valves flutter.
                                  Needless to say a lot people threw valves and blew their engines up.

                                  Moral of the story, the Chinese don’t care about the product they produce just as long as you buy it.
                                  Like c’mon, we’re talking about people that sell switch blades and ZK’s on wish here hahaha

                                  But yeah, furthermore having seen how many things like spark plugs or even V force’s have counterfeit reproductions I always take the time to background check the seller so I ain’t being mugged off.

                                  CalumC 1 Reply Last reply
                                  0
                                  • Stevie WonderS Stevie Wonder

                                    @Calum said in Trying to fix an issue:

                                    Whatever you do, DO NOT and I mean DO NOT buy those shitty fucking Chinese "Racing Coils". Go Genuine or Go Home!

                                    Oh fuck no! 🤮

                                    Racing CDI’s used to be all the rage when I was tuning my lexmoto a few years back that was until everyone cottoned on the fact it turns a bike with a perfectly good hardline ignition and then removes the limiter all together so the bike could Rev so high the valves flutter.
                                    Needless to say a lot people threw valves and blew their engines up.

                                    Moral of the story, the Chinese don’t care about the product they produce just as long as you buy it.
                                    Like c’mon, we’re talking about people that sell switch blades and ZK’s on wish here hahaha

                                    But yeah, furthermore having seen how many things like spark plugs or even V force’s have counterfeit reproductions I always take the time to background check the seller so I ain’t being mugged off.

                                    CalumC Offline
                                    CalumC Offline
                                    Calum
                                    wrote on last edited by
                                    #62

                                    @Stevie-Wonder Coil not CDI. I run Zeeltronic and it's the single most beneficial upgrade to my bikes. But I made the mistake in buying this Racing Coil Junk that worked fine initially, then developed a fault and I could understand what was causing it.

                                    alt text

                                    You'll know it when you see it!

                                    Always Originate, Never Pirate!

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                                    • Stevie WonderS Offline
                                      Stevie WonderS Offline
                                      Stevie Wonder
                                      wrote on last edited by
                                      #63

                                      Update pretty sure bikes just blown up as I type this.

                                      Popped out for the local meet, bike had been swell besides the previously mentioned issues then one minute, nothing.

                                      I got the bike started a couple times but noticed huge amounts of smoke pouring out behind me as the bike limped and struggled up the road

                                      I got off and smell was nauseas and toxic smelling as anything

                                      And now I am stuck on the corner of a road for two days running

                                      CalumC 1 Reply Last reply
                                      0
                                      • Stevie WonderS Stevie Wonder

                                        Update pretty sure bikes just blown up as I type this.

                                        Popped out for the local meet, bike had been swell besides the previously mentioned issues then one minute, nothing.

                                        I got the bike started a couple times but noticed huge amounts of smoke pouring out behind me as the bike limped and struggled up the road

                                        I got off and smell was nauseas and toxic smelling as anything

                                        And now I am stuck on the corner of a road for two days running

                                        CalumC Offline
                                        CalumC Offline
                                        Calum
                                        wrote on last edited by
                                        #64

                                        @Stevie-Wonder Huge smoke, either head gasket or oil seal. Not exactly "Blown Up". It wouldn't run if that's the case.

                                        Always Originate, Never Pirate!

                                        Stevie WonderS 1 Reply Last reply
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                                        • CalumC Calum

                                          @Stevie-Wonder Huge smoke, either head gasket or oil seal. Not exactly "Blown Up". It wouldn't run if that's the case.

                                          Stevie WonderS Offline
                                          Stevie WonderS Offline
                                          Stevie Wonder
                                          wrote on last edited by
                                          #65

                                          @Calum I can confirm having spent 10-15 minutes continuously kicking it from TDC that it will not run 😂

                                          Occasionally it’ll catch a spark but that’s followed by loads of smoke, same as while kicking it really

                                          For now das ist kaput!

                                          CalumC S 2 Replies Last reply
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