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DT125R FORUM

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  4. The Helios Project (Aprilia RS 125 Rotax 122 Biaggi Race Replica)

The Helios Project (Aprilia RS 125 Rotax 122 Biaggi Race Replica)

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  • CalumC Calum

    @finnerz89 Spot on mate. How did you know?

    declanD Offline
    declanD Offline
    declan
    wrote on last edited by
    #91

    @calum damn give me a chance lol

    1 Reply Last reply
    0
    • CalumC Offline
      CalumC Offline
      Calum
      wrote on last edited by
      #92

      Front Mud Guards Arrived

      alt text
      alt text

      I look forward to fitting that this weekend 😄

      Always Originate, Never Pirate!

      declanD NINJAN 2 Replies Last reply
      0
      • CalumC Calum

        Front Mud Guards Arrived

        alt text
        alt text

        I look forward to fitting that this weekend 😄

        declanD Offline
        declanD Offline
        declan
        wrote on last edited by
        #93

        @calum that looks slick how’s the engine coming along?

        CalumC 1 Reply Last reply
        0
        • declanD declan

          @calum that looks slick how’s the engine coming along?

          CalumC Offline
          CalumC Offline
          Calum
          wrote on last edited by
          #94

          @declan Should have some updates later in the week.

          Always Originate, Never Pirate!

          1 Reply Last reply
          0
          • CalumC Calum

            @finnerz89 Spot on mate. How did you know?

            F Offline
            F Offline
            finnerz89
            wrote on last edited by
            #95

            @calum I've had 2 bikes with hydraulic clutches, recognised the cylinder lol

            Current bikes:
            DT125X '07
            Street Triple R '11
            Aprilia ETV1000 '02

            Previous:
            DR650RSE '96
            FJ1200 '92

            1 Reply Last reply
            1
            • CalumC Calum

              Front Mud Guards Arrived

              alt text
              alt text

              I look forward to fitting that this weekend 😄

              NINJAN Offline
              NINJAN Offline
              NINJA
              wrote on last edited by
              #96

              @calum I'm just curious, are the Magura Hydro clutches not compatible???

              SEDUCED BY THE DARK SIDE!!!

              CalumC 1 Reply Last reply
              0
              • NINJAN NINJA

                @calum I'm just curious, are the Magura Hydro clutches not compatible???

                CalumC Offline
                CalumC Offline
                Calum
                wrote on last edited by Calum
                #97

                @ninja They're mega bucks though ain't they.

                And probably not.

                This is the clutch actuation on these engines

                alt text

                Always Originate, Never Pirate!

                1 Reply Last reply
                0
                • MiniaM Offline
                  MiniaM Offline
                  Minia
                  wrote on last edited by
                  #98

                  This is really looking sweet 🙂

                  Yamaha DT125R Blue 2002, XT 125 1982, Yamaha WR250Z 1992, BMW GS650F 1994, Benelli BN302 2015

                  1 Reply Last reply
                  0
                  • CalumC Calum

                    Updates are coming...

                    But who can guess what custom modifications I will be doing on my RS?

                    alt text

                    I won't take credit for the idea. I always wanted to do it on my DT, but just couldn't justify the price.

                    I then found a thread detailing a certain other bike made by Honda, whom did the exact conversion on these engines.

                    HM CRE 125 if you're wondering. Looks awesomse, same engine as these RS's, except they ran electronic oil inject for 50% less oil consumption. Amongst other mods.

                    But after not being able to find the parts I wanted, I gave up.

                    Then I found this build thread on a certain other website, and mans was like...yes I'm doing that.

                    NINJAN Offline
                    NINJAN Offline
                    NINJA
                    wrote on last edited by
                    #99

                    @calum The Magura clutches are expensive, but apart from the cheap Chinese ones on ebay, there's not a lot else too choose from. I want one on my MX for-sure, can you post a link to the thread you found detailing the hydro conversion please???

                    SEDUCED BY THE DARK SIDE!!!

                    CalumC 1 Reply Last reply
                    0
                    • NINJAN NINJA

                      @calum The Magura clutches are expensive, but apart from the cheap Chinese ones on ebay, there's not a lot else too choose from. I want one on my MX for-sure, can you post a link to the thread you found detailing the hydro conversion please???

                      CalumC Offline
                      CalumC Offline
                      Calum
                      wrote on last edited by
                      #100

                      @ninja You won't like it, lol. It was using PhotoFuckit and all the photos are messed up.

                      I'll have this one done by the end of the week.

                      Here is how Honda did it

                      alt text
                      alt text

                      They've used the original clutch actuation for it.

                      Here is the thread.

                      http://www.125ccsportsbikes.com/forums/index.php?showtopic=100907

                      Always Originate, Never Pirate!

                      NINJAN 1 Reply Last reply
                      1
                      • CalumC Calum

                        @ninja You won't like it, lol. It was using PhotoFuckit and all the photos are messed up.

                        I'll have this one done by the end of the week.

                        Here is how Honda did it

                        alt text
                        alt text

                        They've used the original clutch actuation for it.

                        Here is the thread.

                        http://www.125ccsportsbikes.com/forums/index.php?showtopic=100907

                        NINJAN Offline
                        NINJAN Offline
                        NINJA
                        wrote on last edited by
                        #101

                        @calum OK Thanks, perhaps if you have the time you could post a tutorial on how to do it and the parts needed etc. please. 😉

                        SEDUCED BY THE DARK SIDE!!!

                        CalumC 1 Reply Last reply
                        0
                        • NINJAN NINJA

                          @calum OK Thanks, perhaps if you have the time you could post a tutorial on how to do it and the parts needed etc. please. 😉

                          CalumC Offline
                          CalumC Offline
                          Calum
                          wrote on last edited by
                          #102

                          @ninja I plan to 😄

                          Always Originate, Never Pirate!

                          NINJAN 1 Reply Last reply
                          1
                          • CalumC Calum

                            @ninja I plan to 😄

                            NINJAN Offline
                            NINJAN Offline
                            NINJA
                            wrote on last edited by
                            #103

                            @calum COOL Thanks, does either bike have the choke/hot start lever incorporated in the overall clutch lever/mount???

                            SEDUCED BY THE DARK SIDE!!!

                            CalumC 1 Reply Last reply
                            0
                            • NINJAN NINJA

                              @calum COOL Thanks, does either bike have the choke/hot start lever incorporated in the overall clutch lever/mount???

                              CalumC Offline
                              CalumC Offline
                              Calum
                              wrote on last edited by
                              #104

                              @ninja Built into the left hand controls.

                              Always Originate, Never Pirate!

                              1 Reply Last reply
                              0
                              • NINJAN Offline
                                NINJAN Offline
                                NINJA
                                wrote on last edited by NINJA
                                #105

                                I want a SuMo one;

                                https://www.youtube.com/watch?v=Nxxasvsbe_Y

                                SEDUCED BY THE DARK SIDE!!!

                                CalumC 1 Reply Last reply
                                1
                                • NINJAN NINJA

                                  I want a SuMo one;

                                  https://www.youtube.com/watch?v=Nxxasvsbe_Y

                                  CalumC Offline
                                  CalumC Offline
                                  Calum
                                  wrote on last edited by
                                  #106

                                  @ninja I know mate, but you got to import them and by which time they are really expensive.

                                  Always Originate, Never Pirate!

                                  NINJAN 1 Reply Last reply
                                  0
                                  • CalumC Calum

                                    @ninja I know mate, but you got to import them and by which time they are really expensive.

                                    NINJAN Offline
                                    NINJAN Offline
                                    NINJA
                                    wrote on last edited by
                                    #107

                                    @calum True but isn't owning rare gems every enthusiast's dreams???

                                    SEDUCED BY THE DARK SIDE!!!

                                    CalumC 1 Reply Last reply
                                    0
                                    • NINJAN NINJA

                                      @calum True but isn't owning rare gems every enthusiast's dreams???

                                      CalumC Offline
                                      CalumC Offline
                                      Calum
                                      wrote on last edited by
                                      #108

                                      @ninja I think, for the money, you could have a supermoto Honda CR500.

                                      So it's kinda like, well they're rarer and better.

                                      Always Originate, Never Pirate!

                                      1 Reply Last reply
                                      0
                                      • CalumC Offline
                                        CalumC Offline
                                        Calum
                                        wrote on last edited by Calum
                                        #109

                                        So this arrived this morning.

                                        alt text

                                        It's the Italkit Gilardoni 140cc cylinder kit for the Rotax 122 engine.

                                        I feel like a bit of history is needed to really appreciate this cylinder.

                                        Gilardoni is the original designer of the Rotax 122 cylinder way back when.

                                        alt text

                                        Original Barrel for reference

                                        A few years ago he revises the cylinder in the form of this cylinder. This cylinder reflects lessons learnt over all of the years people have been racing these engines. All of this is reflected in the barrels design.

                                        alt text

                                        alt text

                                        Now I was tossing and turning trying to decide what route to take with this engine. Initially, sticking with the Gilardoni Rotax 122 original cylinder, opting to have it ported to reflect my systems designed.

                                        But no matter what engine I bought, the cylinders were all scrap,and it was going to cost £300 to remanufacture the cylinder to usable condition.

                                        I have ridden Aprilia RS 125's since I was 16, that's a little under a decade of riding experience on these engines alone. I have ridden bad ones and I've ridden good ones. I've ridden bog standard ones, and highly tuned ones.

                                        The thing that stuck in my mind the most is how the original engine revs to 14K, and I always appreciated that out of the original cylinder.

                                        When riding Polini's 160cc kit, you lose around 2K over rev. This isn't the case with this barrel. It'll continue to pull hard to 14k, granted it's not the extra CC's that give you the bang.

                                        The porting work on this engine is superfluous, it's extremely well done for a casted material.

                                        alt text
                                        alt text

                                        Sure there are further refinements that could be done here, a few edges taken off and some minor flaws altered, but on the whole, it's a very well designed cylinder.

                                        Combine this with PJME's Reworked VHM billet head, and you have yourself a very capable top end.

                                        alt text

                                        The cylinder is running a relatively high 12.1:1 compression ratio, less than ideal for reliable road use. The fueling on this cylinder needs to be finely tuned to avoid running the risk of detonation. This engine must be run on Shell Super Unleaded, else it's just going to detonate.

                                        alt text

                                        All this power is no good if you can't stop for the corners.

                                        alt text

                                        I've ran these on my DT, with the older style Aprilia braking system. So running this on the radials will surely surprise me.

                                        These Brembo Sintered brakes are £40 a pop, if you can find a set. Were sold out everyone I looked.

                                        I refurbished the brakes themselves back in Christmas time, and I've just ordered titanium retainer pins and titanium bolts to fix it to the forks.

                                        alt text

                                        alt text

                                        So far so good.

                                        I need to calculate the squish on the engine I'm building to ensure I get the right compression ratio, then drop the engine into the frame.

                                        I need to order some titanium head bolts, V-Force3 Reed cage and 34mm inlet. The dellorto racing carburettor has been ordered. Some £1000 spent this month already, with more to follow...

                                        Always Originate, Never Pirate!

                                        declanD 1 Reply Last reply
                                        0
                                        • CalumC Calum

                                          So this arrived this morning.

                                          alt text

                                          It's the Italkit Gilardoni 140cc cylinder kit for the Rotax 122 engine.

                                          I feel like a bit of history is needed to really appreciate this cylinder.

                                          Gilardoni is the original designer of the Rotax 122 cylinder way back when.

                                          alt text

                                          Original Barrel for reference

                                          A few years ago he revises the cylinder in the form of this cylinder. This cylinder reflects lessons learnt over all of the years people have been racing these engines. All of this is reflected in the barrels design.

                                          alt text

                                          alt text

                                          Now I was tossing and turning trying to decide what route to take with this engine. Initially, sticking with the Gilardoni Rotax 122 original cylinder, opting to have it ported to reflect my systems designed.

                                          But no matter what engine I bought, the cylinders were all scrap,and it was going to cost £300 to remanufacture the cylinder to usable condition.

                                          I have ridden Aprilia RS 125's since I was 16, that's a little under a decade of riding experience on these engines alone. I have ridden bad ones and I've ridden good ones. I've ridden bog standard ones, and highly tuned ones.

                                          The thing that stuck in my mind the most is how the original engine revs to 14K, and I always appreciated that out of the original cylinder.

                                          When riding Polini's 160cc kit, you lose around 2K over rev. This isn't the case with this barrel. It'll continue to pull hard to 14k, granted it's not the extra CC's that give you the bang.

                                          The porting work on this engine is superfluous, it's extremely well done for a casted material.

                                          alt text
                                          alt text

                                          Sure there are further refinements that could be done here, a few edges taken off and some minor flaws altered, but on the whole, it's a very well designed cylinder.

                                          Combine this with PJME's Reworked VHM billet head, and you have yourself a very capable top end.

                                          alt text

                                          The cylinder is running a relatively high 12.1:1 compression ratio, less than ideal for reliable road use. The fueling on this cylinder needs to be finely tuned to avoid running the risk of detonation. This engine must be run on Shell Super Unleaded, else it's just going to detonate.

                                          alt text

                                          All this power is no good if you can't stop for the corners.

                                          alt text

                                          I've ran these on my DT, with the older style Aprilia braking system. So running this on the radials will surely surprise me.

                                          These Brembo Sintered brakes are £40 a pop, if you can find a set. Were sold out everyone I looked.

                                          I refurbished the brakes themselves back in Christmas time, and I've just ordered titanium retainer pins and titanium bolts to fix it to the forks.

                                          alt text

                                          alt text

                                          So far so good.

                                          I need to calculate the squish on the engine I'm building to ensure I get the right compression ratio, then drop the engine into the frame.

                                          I need to order some titanium head bolts, V-Force3 Reed cage and 34mm inlet. The dellorto racing carburettor has been ordered. Some £1000 spent this month already, with more to follow...

                                          declanD Offline
                                          declanD Offline
                                          declan
                                          wrote on last edited by
                                          #110

                                          @calum im expecting the very first attempt to start the bike on here 🤤

                                          CalumC 1 Reply Last reply
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