Skip to content
  • Recent
  • Tags
  • Popular
  • Users
  • Groups
Skins
  • Light
  • Cerulean
  • Cosmo
  • Flatly
  • Journal
  • Litera
  • Lumen
  • Lux
  • Materia
  • Minty
  • Morph
  • Pulse
  • Sandstone
  • Simplex
  • Sketchy
  • Spacelab
  • United
  • Yeti
  • Zephyr
  • Dark
  • Cyborg
  • Darkly
  • Quartz
  • Slate
  • Solar
  • Superhero
  • Vapor

  • Default (Slate)
  • No Skin
Collapse
Brand Logo

DT125R FORUM

  1. Home
  2. Owners Build Threads
  3. DTR
  4. DT 125 R '88... New project

DT 125 R '88... New project

Scheduled Pinned Locked Moved DTR
89 Posts 11 Posters 26.1k Views 1 Watching
  • Oldest to Newest
  • Newest to Oldest
  • Most Votes
Reply
  • Reply as topic
Log in to reply
This topic has been deleted. Only users with topic management privileges can see it.
  • J Offline
    J Offline
    jgr72
    wrote on last edited by
    #25

    Few days ago I changed original snorkel to an DT230 Lanza version... Few decals arrived also from ebay... Not changing them now... later... maybe during winter... If I decide to take the bike in parts and do some painting to body and rear swing...

    Been sitting in google for hours and days 😄 ... searching for something fun:
    maybe I will change Gianelli exhaust, Athena 170cc cyl kit and mikuni TM30 carburetor during winter... Those shoud give me more pleasure to ride 🙂 And still keep original look... Need to work hard to make the money for that 😄 😄 😄

    1 Reply Last reply
    1
    • J Offline
      J Offline
      jgr72
      wrote on last edited by
      #26

      A little update... Today I fixed front brake... Sealing was worn, and it would be only matter of time, when the brake cylinder would stuck totally... It was already a bit lazy I think... I did it just in time, there ware some corrosion in brake caliper, but I used sand paper and decide that it's still useful... Piston was in excellent condition... Old brake fluid was quite black and shitty... perhaps original and nearly 30 years old? Then caliper rebuild with new sealing and gasket... Tomorrow I have to bleed air away from the system... It looks like I have to use pressured air to force brake fluid into caliper... Brake lever is now doing nothing 😄 Sorry that I was too lazy to take any photos...

      I found myself from ordering a new carb... Mikuni TM30... and it's on the way already 😛 And earlier I also ordered DT230 Lanza version of carburetor -> air box joint... Lanza item should be direct fit to TM30 carb and maybe some minor modification to the original air box... On the engine side, the diameter difference (VM28 vs TM30) is only 1mm bigger, I assume it will fit to the original intake rubber... TM30 is also 5mm longer, but that shouldn't be any problem...

      Anyone have idea for right main jet? 160? 170? 180?

      Silocone tubes arrived yesterday, I will replace all 2-stroke oil feed tubes from oiltank, to carb...

      1 Reply Last reply
      1
      • J Offline
        J Offline
        jgr72
        wrote on last edited by
        #27

        Today I changed leaking autolube hoses to a silicone one... I ordered them from ebay many weeks ago and they arrived few days ago... It was an easy job to do. Tank to autolube pump hose was nice fit with 5mm silicone hose. Autolube pump to carb was nice fit with 3mm hose. But be aware if you bleed whole pump empty, it might not be able to suck oil from tank!!! Be careful when you start the engine!!! I have to squirt oil direct in to the pump and open air screw in order to get the air out from the pump. Here are from photos from that job...

        Dissolution:
        alt text

        Pump to carb hose size:
        alt text

        Tank to pump hose:
        alt text

        Pump to carb hose in place:
        alt text

        Tank to pump hose in place:
        alt text

        Ready to ride:
        alt text

        CalumC 1 Reply Last reply
        2
        • J jgr72

          Today I changed leaking autolube hoses to a silicone one... I ordered them from ebay many weeks ago and they arrived few days ago... It was an easy job to do. Tank to autolube pump hose was nice fit with 5mm silicone hose. Autolube pump to carb was nice fit with 3mm hose. But be aware if you bleed whole pump empty, it might not be able to suck oil from tank!!! Be careful when you start the engine!!! I have to squirt oil direct in to the pump and open air screw in order to get the air out from the pump. Here are from photos from that job...

          Dissolution:
          alt text

          Pump to carb hose size:
          alt text

          Tank to pump hose:
          alt text

          Pump to carb hose in place:
          alt text

          Tank to pump hose in place:
          alt text

          Ready to ride:
          alt text

          CalumC Offline
          CalumC Offline
          Calum
          wrote on last edited by
          #28

          @jgr72 Nice clear lionesis what I like to see.

          Keeping an eye on that oil 😉

          Always Originate, Never Pirate!

          1 Reply Last reply
          1
          • J Offline
            J Offline
            jgr72
            wrote on last edited by jgr72
            #29

            Yeah, actually it was nice to see how the oil travels in pump to carb hose... I had red oil and air in that hose, and it travels with a rythm 💃 And it was easy to see how it works when you rev the engine...

            1 Reply Last reply
            3
            • MightymanM Offline
              MightymanM Offline
              Mightyman
              wrote on last edited by
              #30

              Very nice, hopefully others can come across this thread if they want to swap their own hoses out for clear ones. 👍

              TDR 125 - 2001

              1 Reply Last reply
              0
              • J Offline
                J Offline
                jgr72
                wrote on last edited by
                #31

                Thats why I took those photos! Internet is a information source 🙂

                1 Reply Last reply
                0
                • J Offline
                  J Offline
                  jgr72
                  wrote on last edited by
                  #32

                  Santa Claus came early this year 🙂 I received TM30 & 230 Lanza air joint in a same day 🙂 It's a great match with those two! Let's see later how it will fit into DT125R airbox 😄 Sadly I don't have any main jets between 150 and 200 range... I've been told that 170 might be right main jet to start from... Also need to drill a hole to the TM30 for oil feed anyway, and don't have that hose nose yet... I'll come later on with pics when I'm installing that... Here are some pictures of todays treasure:

                  Yamaha DT 230 Lanza carburetor -> air box joint:
                  alt text

                  It a great match together:
                  alt text

                  alt text

                  alt text

                  alt text

                  CalumC 1 Reply Last reply
                  4
                  • J jgr72

                    Santa Claus came early this year 🙂 I received TM30 & 230 Lanza air joint in a same day 🙂 It's a great match with those two! Let's see later how it will fit into DT125R airbox 😄 Sadly I don't have any main jets between 150 and 200 range... I've been told that 170 might be right main jet to start from... Also need to drill a hole to the TM30 for oil feed anyway, and don't have that hose nose yet... I'll come later on with pics when I'm installing that... Here are some pictures of todays treasure:

                    Yamaha DT 230 Lanza carburetor -> air box joint:
                    alt text

                    It a great match together:
                    alt text

                    alt text

                    alt text

                    alt text

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

                    @jgr72 Looking good buddy!

                    Always Originate, Never Pirate!

                    1 Reply Last reply
                    0
                    • A Offline
                      A Offline
                      andrewj1680
                      wrote on last edited by
                      #34

                      How did this setup workout for you?

                      1 Reply Last reply
                      0
                      • J Offline
                        J Offline
                        jgr72
                        wrote on last edited by
                        #35

                        Actually I haven't tried it yet... But it supposed to be a good setup!? Original carb feels a bit out of right setup... It feels rich in mid rev and it won't rev above 8k... top speed is hardly 110km/h. But I have no intention to do anything for it... new carb is only waiting to "step in" 😄

                        Still waiting for that oil hose nose from ebay... It's taking many weeks from china to europe sometimes... Meanwhile I had to do something... I drilled a 2.5mm hole for oil feed hose nose and tapped M3 threads with a screw drive style handle... M3 is so small and alu so soft that it was an easy to turn...

                        alt text

                        alt text

                        1 Reply Last reply
                        1
                        • J Offline
                          J Offline
                          jgr72
                          wrote on last edited by
                          #36

                          Finally hose noses arrived:

                          I bought few of them in case I need one in future...

                          alt text

                          There it is... I also added some "thread glue":

                          alt text

                          alt text/20170704_092559.jpg)

                          alt text

                          Okey, now I have all I need to change the carb. But how about the carb throttle cable? Is it a straight swap, or do I have to make some modifications? I've been trying to find answers from google...

                          declanD 1 Reply Last reply
                          1
                          • J jgr72

                            Finally hose noses arrived:

                            I bought few of them in case I need one in future...

                            alt text

                            There it is... I also added some "thread glue":

                            alt text

                            alt text/20170704_092559.jpg)

                            alt text

                            Okey, now I have all I need to change the carb. But how about the carb throttle cable? Is it a straight swap, or do I have to make some modifications? I've been trying to find answers from google...

                            declanD Offline
                            declanD Offline
                            declan
                            wrote on last edited by
                            #37

                            @jgr72 it should fit but the only way to know for sure is to actually try it

                            1 Reply Last reply
                            0
                            • CalumC Offline
                              CalumC Offline
                              Calum
                              wrote on last edited by
                              #38

                              For my dellorto VHSA carb the cable needed modifying.

                              Always Originate, Never Pirate!

                              1 Reply Last reply
                              0
                              • J Offline
                                J Offline
                                jgr72
                                wrote on last edited by jgr72
                                #39

                                Yes, it fits, but I need to strip throttle cable about 30mm... Sorry that my phone focus to the engine, and not the cable 😄 :

                                alt text

                                But there it is now:

                                alt text

                                alt text

                                TM30 comes quite close to clutch, it can't be installed straight... must be a little bit askew... Maybe some other intake would give better position?:

                                alt text

                                Next problem is this:

                                alt text

                                alt text

                                It wouldn't line up nice... Maybe DT230 Lanza intake would correct this problem?

                                Or then I just make my own boot for universal air filter, and forget the whole original airbox... I tried the bike without air filter and it runs quite nice, no torque loss at low rpm, and still have more power at high rpm... feels good, even I might not have the best jetting setup jet... If I remember right, the best main jet was 135 etc...

                                But... I can't ride without an air filter, and I need to fine some solution that I can ride with while I'm planning my next move:

                                alt text

                                I sprayed urethane, and "glued" 50mm alu pipe to the air box 😄 This wasn't a very professional style, but its easy to remove and airbox is still original, while I don't know what to do next 😄

                                CalumC 1 Reply Last reply
                                2
                                • J jgr72

                                  Yes, it fits, but I need to strip throttle cable about 30mm... Sorry that my phone focus to the engine, and not the cable 😄 :

                                  alt text

                                  But there it is now:

                                  alt text

                                  alt text

                                  TM30 comes quite close to clutch, it can't be installed straight... must be a little bit askew... Maybe some other intake would give better position?:

                                  alt text

                                  Next problem is this:

                                  alt text

                                  alt text

                                  It wouldn't line up nice... Maybe DT230 Lanza intake would correct this problem?

                                  Or then I just make my own boot for universal air filter, and forget the whole original airbox... I tried the bike without air filter and it runs quite nice, no torque loss at low rpm, and still have more power at high rpm... feels good, even I might not have the best jetting setup jet... If I remember right, the best main jet was 135 etc...

                                  But... I can't ride without an air filter, and I need to fine some solution that I can ride with while I'm planning my next move:

                                  alt text

                                  I sprayed urethane, and "glued" 50mm alu pipe to the air box 😄 This wasn't a very professional style, but its easy to remove and airbox is still original, while I don't know what to do next 😄

                                  CalumC Offline
                                  CalumC Offline
                                  Calum
                                  wrote on last edited by
                                  #40

                                  @jgr72 You are running a 3BN barrel.

                                  They have slightly shorter strokes with bigger bores than the classic 3MB. Be mindful of that when it comes to engine rebuild time.

                                  Always Originate, Never Pirate!

                                  1 Reply Last reply
                                  0
                                  • J Offline
                                    J Offline
                                    jgr72
                                    wrote on last edited by jgr72
                                    #41

                                    Okey, owners manual says that bore is 56mm and stroke 50.7... Does Athena 170cc kit fit into this?

                                    By the way, someone claims that this bike std carb is 26mm mikuni, here's snap from owners manual, and it clearly says TM28SS:

                                    alt text

                                    Isn't TM a flat slide and VM round slide? Carb that I took away, was 28mm round slide! Isn't that a VM28?

                                    1 Reply Last reply
                                    0
                                    • J Offline
                                      J Offline
                                      jgr72
                                      wrote on last edited by
                                      #42

                                      Now I'm confused, manual of an 3MB page 84 says that 3MB is also 56x50.7:

                                      link text

                                      1 Reply Last reply
                                      0
                                      • CalumC Offline
                                        CalumC Offline
                                        Calum
                                        wrote on last edited by
                                        #43

                                        Again, if your barrel was the 3MB this would be correct.

                                        It's not it's the 3BN which I think were off really early DTR's before they swapped the carb for a 28mm and a 3MB barrel.

                                        So no, Athena 170 kit is not designed for this engine. You will need to put a 3MB connecting rod, assuming it's just the rod length that's changed, or a 3MB crank.

                                        It's not anything big, I just thought I'd mention it incase you wanted to rebuild the engine, it is ever so slightly different.

                                        Always Originate, Never Pirate!

                                        1 Reply Last reply
                                        0
                                        • J Offline
                                          J Offline
                                          jgr72
                                          wrote on last edited by
                                          #44

                                          Okey, barrel have 3BN00 stamp on it... I think I will rebuild it someday... I'll get back then 😄 Hmm... 3MB crank & rod + 3BN piston and barrel would give a little bigger engine 😄

                                          CalumC 1 Reply Last reply
                                          1
                                          Reply
                                          • Reply as topic
                                          Log in to reply
                                          • Oldest to Newest
                                          • Newest to Oldest
                                          • Most Votes


                                          • Login

                                          • Don't have an account? Register

                                          • Login or register to search.
                                          • First post
                                            Last post
                                          0
                                          • Recent
                                          • Tags
                                          • Popular
                                          • Users
                                          • Groups