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DT125R FORUM

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Runs with choke

Scheduled Pinned Locked Moved Engine
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  • OllieDTRO OllieDTR

    @SpookDog

    Fixed it!!!

    So airscrew didn’t have a o ring so put one in.
    Also when I was checking air leaks nothing, so I thought I’d take carb out and check all rubbers, where the jubliee clip tightens up onto the carb on inlet there was a hairline crack under the clip which I only saw when I flexed it about. so put the carb back on and sprayed like 2mm away from the place I saw the crack and sure thing revved up. So that’s why I didn’t rev before when I sprayed because I had to be really really close to it!

    After all that 😅 I’m glad though crazy how a tiny tiny little crack can do that but where it was hidden under the clip it didn’t pick up the brake cleaner until really close.

    Thank you everyone been a couple of stressful days but that’s a win and learn something on the way

    HOTSHOT IIIH Offline
    HOTSHOT IIIH Offline
    HOTSHOT III
    wrote on last edited by
    #45

    @OllieDTR Cool you've fixed it 👍 👍 Here you go bud, DTRe 1D01-1D03 (2004-onwards) wiring diagram as discussed:

    alt text

    I'd still try those washers above and below the carb needle E-clip, stopping that moving up and down too much will be no bad thing. And here's a pic of my airbox when I sealed it up, this is why I like to take them out to do this so the part you've glued can sit on the bench horizontally while the glue goes off. While you've got the Seal-All out you can also replace the foam on the back of the filter element holder where it slides into the airbox as this is another thing "previous owners" miss, it rots out providing another route for dirt to get in. 5mm air filter foam is pretty cheap on eBay etc.

    alt text

    https://www.repairingproducts.co.uk/product/seal-all-gas-oil-resistant-adhesive/

    1 Reply Last reply
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    • OllieDTRO OllieDTR

      @SpookDog

      Fixed it!!!

      So airscrew didn’t have a o ring so put one in.
      Also when I was checking air leaks nothing, so I thought I’d take carb out and check all rubbers, where the jubliee clip tightens up onto the carb on inlet there was a hairline crack under the clip which I only saw when I flexed it about. so put the carb back on and sprayed like 2mm away from the place I saw the crack and sure thing revved up. So that’s why I didn’t rev before when I sprayed because I had to be really really close to it!

      After all that 😅 I’m glad though crazy how a tiny tiny little crack can do that but where it was hidden under the clip it didn’t pick up the brake cleaner until really close.

      Thank you everyone been a couple of stressful days but that’s a win and learn something on the way

      S Offline
      S Offline
      SpookDog
      wrote on last edited by
      #46

      @OllieDTR

      Fuxin sweet! All you have to do now is make sure you got the right jetting for the carb! 😛

      Have you got another rubber inlet? I can probably flog you one if needed. I went through a spell of snapping them up after I had my ‘cracking up problems’…

      I did ‘inject’ silicone sealant into the split and around it for a temp fix. Nothing beats a good seal though…

      OllieDTRO 1 Reply Last reply
      1
      • S SpookDog

        @OllieDTR

        Fuxin sweet! All you have to do now is make sure you got the right jetting for the carb! 😛

        Have you got another rubber inlet? I can probably flog you one if needed. I went through a spell of snapping them up after I had my ‘cracking up problems’…

        I did ‘inject’ silicone sealant into the split and around it for a temp fix. Nothing beats a good seal though…

        OllieDTRO Offline
        OllieDTRO Offline
        OllieDTR
        wrote on last edited by
        #47

        @SpookDog

        Result ay mate! Was on the phone with @HOTSHOT-III and we was running through some stuff and made me think to double check and check again everything.

        I’ve just picked my spare one up from my mums so will be putting that one on tomorrow.

        As regards of jetting I’ve got

        4th clip on needle
        240 main
        .25 pilot

        I’m sure that’s correct for my year as it’s an DTRE engine.
        I just wasn’t sure if I needed to upjet at all as I’ve got dep, Boyseen dual stage reeds and 1mm oversize re bore?

        I will do a plug chop when it’s all running properly and go from there

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        • OllieDTRO Offline
          OllieDTRO Offline
          OllieDTR
          wrote on last edited by
          #48
          This post is deleted!
          1 Reply Last reply
          0
          • CalumC Offline
            CalumC Offline
            Calum
            wrote on last edited by
            #49

            Sounds like it's running lean on fuel then. There is a good guide on here to jetting. Sounds like you've got either two options.

            Put it back to standard, or jet to suit. I'd just do the latter. A bit of playing around, but you'll get it I'm sure.

            Always Originate, Never Pirate!

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            • OllieDTRO Offline
              OllieDTRO Offline
              OllieDTR
              wrote on last edited by
              #50

              @SpookDog @HOTSHOT-III

              I feel like a right idiot…

              So the main problem was the split in the inlet rubber got new one on. But when I was changing the jets I had a jet that came in the carb already and that 20 pilot from mikuni I put it next to a .20 pilot I had from my new jets and the new jet holes was tiny compared to this one, to get the same size holes from my new jets compared to this 20 I had would be like a 35…

              Never buy jets from eBay that’s a Chinese seller I guess

              So anyways my mates got a dt so I rang him up and borrowed a 25 pilot and sure thing it ran the sweetest ever!! So now I need to order a 25 pilot from a good company also will probably get a 240 main jet aswell while I’m at it

              S 1 Reply Last reply
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              • OllieDTRO OllieDTR

                @SpookDog @HOTSHOT-III

                I feel like a right idiot…

                So the main problem was the split in the inlet rubber got new one on. But when I was changing the jets I had a jet that came in the carb already and that 20 pilot from mikuni I put it next to a .20 pilot I had from my new jets and the new jet holes was tiny compared to this one, to get the same size holes from my new jets compared to this 20 I had would be like a 35…

                Never buy jets from eBay that’s a Chinese seller I guess

                So anyways my mates got a dt so I rang him up and borrowed a 25 pilot and sure thing it ran the sweetest ever!! So now I need to order a 25 pilot from a good company also will probably get a 240 main jet aswell while I’m at it

                S Offline
                S Offline
                SpookDog
                wrote on last edited by SpookDog
                #51

                @OllieDTR

                Bud! I’ve done the fleabay SHITTY jet thing myself. Don’t beat yourself up, it’s all a learning curve 🙂 …

                I got a good aftermarket .25 jet from
                Sportaxracing. The difference it made to my bike was unbelievable. Starts first kick, ticks over and revs up crisp and clean. It’s where I’d go…

                I’ve also bought ‘EBC’ jets that were shite, because getting a Mikuni genuine.25 is impossible in the UK. I don’t know if a genuine 240 is possible either…

                I’m happy for you that it’s running sweet! 😇

                OllieDTRO 1 Reply Last reply
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                • S SpookDog

                  @OllieDTR

                  Bud! I’ve done the fleabay SHITTY jet thing myself. Don’t beat yourself up, it’s all a learning curve 🙂 …

                  I got a good aftermarket .25 jet from
                  Sportaxracing. The difference it made to my bike was unbelievable. Starts first kick, ticks over and revs up crisp and clean. It’s where I’d go…

                  I’ve also bought ‘EBC’ jets that were shite, because getting a Mikuni genuine.25 is impossible in the UK. I don’t know if a genuine 240 is possible either…

                  I’m happy for you that it’s running sweet! 😇

                  OllieDTRO Offline
                  OllieDTRO Offline
                  OllieDTR
                  wrote on last edited by
                  #52

                  @SpookDog

                  I was annoyed but pleased at the same time I finally narrowed it down mate!

                  What do you think of these?
                  https://jetsplus.co.uk/product/mikuni-pilot-jet-vm22-210-ax100-en-tzr-tm-2-stroke-4-stroke-10-65/

                  HOTSHOT IIIH 1 Reply Last reply
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                  • OllieDTRO OllieDTR

                    @SpookDog

                    I was annoyed but pleased at the same time I finally narrowed it down mate!

                    What do you think of these?
                    https://jetsplus.co.uk/product/mikuni-pilot-jet-vm22-210-ax100-en-tzr-tm-2-stroke-4-stroke-10-65/

                    HOTSHOT IIIH Offline
                    HOTSHOT IIIH Offline
                    HOTSHOT III
                    wrote on last edited by
                    #53

                    @OllieDTR Looks like a good website to me but TBH I've never bought a Mikuni pilot jet so I wouldn't know how to measure them to ensure they're genuine. I think there's a set of gauges you can buy which are just labelled bits of wire the correct diameter.

                    Mikuni main jets you can get from PJME so it might be worth calling them and asking about the pilots, also try Allens Performance in the UK or Mikunioz.com (things posted from Australia arrive surprisingly quickly).

                    https://mikunioz.com/?v=13b249c5dfa9

                    https://www.allensperformance.co.uk/

                    And I'd take a look at Yamaha France parts lookup, get the part numbers of the jets from a late model DTRe and then Google for these because someone somewhere might have a NOS one and if it's in a sealed bag with a Yamaha part number it's bound to be genuine.

                    Yamaha France is a very good resource generally; very accurate and they seem to have info for any Yamaha product, not just those sold in France and on a PC you can just hit Translate. As an experiment I keyed in the VIN number for my original 1990 white/red UK (i.e restricted to 12bhp via no YPVS servo and PV pinned closed) DTR I owned in 1992 and it showed the PV end cap on the barrel instead of the YPVS pulley, cables and servo. Obviously it made no reference to myself and several other teenage malcontents accidentaly on purpose reassembling these components by the side of the road to alter this about an hour after I bought the bike...

                    https://www.yamaha-motor.eu/fr/fr/service-maintenance/parts-catalogue/

                    OllieDTRO 1 Reply Last reply
                    1
                    • HOTSHOT IIIH HOTSHOT III

                      @OllieDTR Looks like a good website to me but TBH I've never bought a Mikuni pilot jet so I wouldn't know how to measure them to ensure they're genuine. I think there's a set of gauges you can buy which are just labelled bits of wire the correct diameter.

                      Mikuni main jets you can get from PJME so it might be worth calling them and asking about the pilots, also try Allens Performance in the UK or Mikunioz.com (things posted from Australia arrive surprisingly quickly).

                      https://mikunioz.com/?v=13b249c5dfa9

                      https://www.allensperformance.co.uk/

                      And I'd take a look at Yamaha France parts lookup, get the part numbers of the jets from a late model DTRe and then Google for these because someone somewhere might have a NOS one and if it's in a sealed bag with a Yamaha part number it's bound to be genuine.

                      Yamaha France is a very good resource generally; very accurate and they seem to have info for any Yamaha product, not just those sold in France and on a PC you can just hit Translate. As an experiment I keyed in the VIN number for my original 1990 white/red UK (i.e restricted to 12bhp via no YPVS servo and PV pinned closed) DTR I owned in 1992 and it showed the PV end cap on the barrel instead of the YPVS pulley, cables and servo. Obviously it made no reference to myself and several other teenage malcontents accidentaly on purpose reassembling these components by the side of the road to alter this about an hour after I bought the bike...

                      https://www.yamaha-motor.eu/fr/fr/service-maintenance/parts-catalogue/

                      OllieDTRO Offline
                      OllieDTRO Offline
                      OllieDTR
                      wrote on last edited by
                      #54

                      @HOTSHOT-III

                      Thank you for all that info bud if doesn’t go un missed!

                      So today I’m going to look at my slide to see what number it has on it, just looking at the emulsion tube needle etc it’s definitely the higher jetting rather than the dtre 210, 17.5

                      As yesterday I tried the 20 pilot that came in the carb and had to have the airscrew right in so definitely needs upjet so I can have it 1 to 1.5 turns out so with the 17.5 the standard DTRE engine has that’ll be to low, maybe it’s because it’s got some “performance mods” on to the bike bike now I don’t know, I’ve ordered from that jets place now looks like one of the better sites and got good reviews, I’ve ordered 210 main, 220 main, and 240,

                      22.5 pilot, 25 pilot and 27.5 pilot just incase I need to go to 27.5 not sure why I would but always good to have incase,

                      I paid £8 before for them other jets that should ring alarm bells as I got like 20 jets for that price😂 and now I’m paying £5 a jet

                      Ready for the road soon 🤞🏻
                      I did order a horn for the bike from AliExpress and it cost me 40p with free shipping and it arrived in 8 days😁 it works like a horn and can’t complain for 40p 😂

                      1 Reply Last reply
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                      • CalumC Offline
                        CalumC Offline
                        Calum
                        wrote on last edited by
                        #55

                        Yeah, if you're going to use aftermarket jets then DON'T JET TO STANDARD! Jet to suit!

                        It's fine to have knock off jets, provided your entire collection is knock off.

                        I just buy genuine jets and stick to genuine.

                        240 genuine may be 210 or 260 knock off. So to say "It's stock jetting" but using aftermarket jets would leave us scratching our heads as to why it isn't working. Potentially leading us to misadvise and cost more money in the long run.

                        I don't have Mikunis in any of my bikes, they are all Dellortos and Eurocarb seems to have me covered on that. Dellortos were also used on the Belgarda engines as well as the Aprilia RS 125s and many Italian bikes. Common scene in the Vespa/Lambretta world and therefore abundance of parts available.

                        Not sure why you're having trouble with Mikunis...

                        Always Originate, Never Pirate!

                        S 1 Reply Last reply
                        0
                        • CalumC Calum

                          Yeah, if you're going to use aftermarket jets then DON'T JET TO STANDARD! Jet to suit!

                          It's fine to have knock off jets, provided your entire collection is knock off.

                          I just buy genuine jets and stick to genuine.

                          240 genuine may be 210 or 260 knock off. So to say "It's stock jetting" but using aftermarket jets would leave us scratching our heads as to why it isn't working. Potentially leading us to misadvise and cost more money in the long run.

                          I don't have Mikunis in any of my bikes, they are all Dellortos and Eurocarb seems to have me covered on that. Dellortos were also used on the Belgarda engines as well as the Aprilia RS 125s and many Italian bikes. Common scene in the Vespa/Lambretta world and therefore abundance of parts available.

                          Not sure why you're having trouble with Mikunis...

                          S Offline
                          S Offline
                          SpookDog
                          wrote on last edited by SpookDog
                          #56

                          @Calum

                          He bought the bike with the wrong jets fitted, You can’t get a .25 Mikuni genuine pilot jet in the UK for love nor money 🙂

                          I got a .25 pilot from sportaxracing and i know the bikes been running sweet since. It’s unmarked but runs perfectly. I really couldn’t comment on the others…

                          Only way to tell a genuine Mikuni jet is that they have a tiny ‘square in another squares corner’ stamped into them…

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                          • OllieDTRO Offline
                            OllieDTRO Offline
                            OllieDTR
                            wrote on last edited by
                            #57

                            So jets arrived today put 25 pilot in and runs a lot better but still hangs for couple seconds before idles good again. Air screw all the way in so needs bigger, I’ve ordered 27.5 and 30 pilot

                            Strange how big it is but all bikes different I guess
                            Mod list

                            Boyseen dual stage reeds with rev plate
                            Dep downpipe and end can

                            CalumC 1 Reply Last reply
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                            • OllieDTRO OllieDTR

                              So jets arrived today put 25 pilot in and runs a lot better but still hangs for couple seconds before idles good again. Air screw all the way in so needs bigger, I’ve ordered 27.5 and 30 pilot

                              Strange how big it is but all bikes different I guess
                              Mod list

                              Boyseen dual stage reeds with rev plate
                              Dep downpipe and end can

                              CalumC Offline
                              CalumC Offline
                              Calum
                              wrote on last edited by
                              #58

                              @OllieDTR to be fair, all my bikes do that to some degree. The revs hang at 2000 rpm before dropping to 1100. But I assumed it was due to lack of oil pump 😂

                              Always Originate, Never Pirate!

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                              • OllieDTRO Offline
                                OllieDTRO Offline
                                OllieDTR
                                wrote on last edited by
                                #59

                                The float height is definitely around 16mm guys? Seen everywhere It’s 20 to 21mm then some places 16mm TM28ss

                                S 2 Replies Last reply
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                                • OllieDTRO OllieDTR

                                  The float height is definitely around 16mm guys? Seen everywhere It’s 20 to 21mm then some places 16mm TM28ss

                                  S Offline
                                  S Offline
                                  SpookDog
                                  wrote on last edited by
                                  #60

                                  @OllieDTR
                                  15~16mm
                                  The 21 is the setting for the 26mm round slide Mikuni fitted to early bikes…

                                  Have you fitted the 240 main? There’s no way you should need a bigger jet than 25. Needle 1 groove up from the bottom. Airscrew 1&1/4 turns out…

                                  S 1 Reply Last reply
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                                  • S SpookDog

                                    @OllieDTR
                                    15~16mm
                                    The 21 is the setting for the 26mm round slide Mikuni fitted to early bikes…

                                    Have you fitted the 240 main? There’s no way you should need a bigger jet than 25. Needle 1 groove up from the bottom. Airscrew 1&1/4 turns out…

                                    S Offline
                                    S Offline
                                    SpookDog
                                    wrote on last edited by SpookDog
                                    #61

                                    If it ran perfectly with your mates genuine.25 Mikuni pilot in it, it’s possible that the one you bought is subpar.

                                    Get a known good one from sportaxracing, they are perfect. Edit: I can absolutely vouch for them 👍 …

                                    It needs the proper main jet as well …

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                                    • OllieDTRO OllieDTR

                                      The float height is definitely around 16mm guys? Seen everywhere It’s 20 to 21mm then some places 16mm TM28ss

                                      S Offline
                                      S Offline
                                      SpookDog
                                      wrote on last edited by
                                      #62

                                      Let us know how you get on with it bud…

                                      OllieDTRO 1 Reply Last reply
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                                      • S SpookDog

                                        Let us know how you get on with it bud…

                                        OllieDTRO Offline
                                        OllieDTRO Offline
                                        OllieDTR
                                        wrote on last edited by
                                        #63

                                        @SpookDog
                                        Right so, the mates 25 pilot jet worked the same as my 25 pilot jet but you had to have the airbox closed off a fair bit for the revs not to hang,

                                        I’ve ordered 27.5 and 30 from sportx place so should be here today 🤞🏻

                                        I tested the bike with them Chinese jets I put the biggest one I had in which was 37.5 obviously it’s not that big in genuine mikuni size but that worked really well with the airbox opened up almost to the size of the snorkel,

                                        I think the 30 pilot will sort it out, I was just thinking if my airscrew is 1.5 turns out and it revs perfect does it matter I’ve got a big pilot?

                                        The way I think of it all bikes are different so they all won’t work on stock jetting? I’ve got 0 air leaks and few mods so can understand it running a bigger pilot?

                                        HOTSHOT IIIH S 2 Replies Last reply
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                                        • OllieDTRO OllieDTR

                                          @SpookDog
                                          Right so, the mates 25 pilot jet worked the same as my 25 pilot jet but you had to have the airbox closed off a fair bit for the revs not to hang,

                                          I’ve ordered 27.5 and 30 from sportx place so should be here today 🤞🏻

                                          I tested the bike with them Chinese jets I put the biggest one I had in which was 37.5 obviously it’s not that big in genuine mikuni size but that worked really well with the airbox opened up almost to the size of the snorkel,

                                          I think the 30 pilot will sort it out, I was just thinking if my airscrew is 1.5 turns out and it revs perfect does it matter I’ve got a big pilot?

                                          The way I think of it all bikes are different so they all won’t work on stock jetting? I’ve got 0 air leaks and few mods so can understand it running a bigger pilot?

                                          HOTSHOT IIIH Offline
                                          HOTSHOT IIIH Offline
                                          HOTSHOT III
                                          wrote on last edited by
                                          #64

                                          @OllieDTR I don't think it matters within reason what size jets you end up running as long as the actual running of the bike is good.

                                          A lot of this kind of stuff is caused by the vagaries of mass production, it's pretty common even with competition bikes for two people to buy the same model off the showroom floor, then find out one runs better than the other when they go out riding.

                                          In the 90s Performance Bikes magazine bought a 500 miles from new damaged repairable Kawasaki KR1-S to make into a road racing bike. It didn't run very well (they dyno'd it at 45bhp and a good one of those is more like 60) so they stripped the engine and found the KIPS valves had been fitted the wrong way round at the factory and some of the port timings were over 1mm out. IIRC they got it blueprinted (which just makes every dimension in the engine exactly what it should be) by Stan Stephens and without any actual tuning this resulted in almost the exact power output Kawasaki claimed when they tested it again. It ended up being faster than some of the "tuned" ones they raced it against!

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