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Engine tuning/ bike build

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  • A Arild

    Its been a while, i just felt like popping in here again and updating everyone, if anyones even interested in my original project anymore, but yeah my cylinder boost porting is still at a standstill. Started school again and dont have the proper stuff to get everything done with that currently but im still planning on doing it so dont worry, with dyno numbers.

    However ive been doing some other things in the garage, when one projects gets put to the side u need to come up with something else to do, so im currently in the middle of building my own homemade intertia dyno. alt text
    alt text
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    Might not look like much, the base of it is an old electrical engine i picked up for free from an electrical engine workshop mechanic place, the rotor might be a little small and light, but it should do fine with 1st gear pulls and seeing as i dont think anything over 30hp will get dynoed on it everything should be fine. Will it give exact numbers? Probably not, more like ballpark numbers, u cant really expect to get numbers youd get on a namebrand dyno from this thing.
    But it will work as a great tuning help, actually being able to visulize if that change you made actually had a positive or negative impact on your engine in the format of an easy to read graph instead of 0-60mph timed runs.

    Coupled together with this i managed to pick up the discontinoued ArDyno arduino pcb shield that Alex from the twostroke stuffing channel on youtube once made. (great guy and great channel that i recommend every bike interested person in this forum to check out)
    alt text
    Im using a crankshaft positioning sensor to monitor the rpms of the rotor
    alt text

    I also while scrolling aliexpress came across some vforce 3 reed valves for around 10 pounds for the honda cr125, so i picked one up since ive heard that the cr125 reeds fit the Dtr engine block.
    alt text
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    Looked and felt good for being a replica from aliexpress

    I had to do some slight surgery to the inlet manifold since these reeds dont use the same style of stuffer that the dtr reeds do
    alt text

    Also hade to take the dremel to the vforce reeds, the actual reed part fit into the engine no problem but the bolt holes didnt line up, so i had to basically open them up so i could fit bolts through everything.
    But its all working good and i dont think its pulling any air through my dremel modifications, can i tell a big difference in how the bike handles? Not really but that might also be because i dont ride it too much, would i be disappointed if i paid the 120 pounds for a real pair? Yes, but since these were a fraction of that im happy with it

    Im planning on designing everything i need in cad and getting it 3d printed so this wont be as much of a hodge podge as it is currently.
    alt text
    alt text

    Last little project ive been working on is putting together another expansion chamber but for my scooter instead, its my daily commuter since i dont have my license to ride the dtr yet, its coming together quite good, its all gonna be painted black before im done so dont worry about the rust
    alt text
    alt text

    Sorry for such a long post that maybe shouldnt be on this forum tbh, hope someone takes the time to read it and finds it interesting, god i wish i could write this much at school

    declanD Offline
    declanD Offline
    declan
    wrote on last edited by
    #8

    @Arild can i get a link to those reeds bud been looking into them my self

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    • declanD declan

      @Arild can i get a link to those reeds bud been looking into them my self

      A Offline
      A Offline
      Arild
      wrote on last edited by
      #9

      @declan

      https://a.aliexpress.com/_mLIIXu7

      These were the ones i got, but u will have to do some modification to the mounting holes which y somewhat can see in the pictures i posted above just so u know, and u will have to cut off the original reed stuffers from the manifold

      declanD 1 Reply Last reply
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      • A Arild

        @declan

        https://a.aliexpress.com/_mLIIXu7

        These were the ones i got, but u will have to do some modification to the mounting holes which y somewhat can see in the pictures i posted above just so u know, and u will have to cut off the original reed stuffers from the manifold

        declanD Offline
        declanD Offline
        declan
        wrote on last edited by
        #10

        @Arild thanks bud

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        • A Offline
          A Offline
          Arild
          wrote on last edited by Arild
          #11

          Hi again everyone, a little update on my dyno project i have going on, im thinking of maybe creating a another thread in the Off Topic section of more in depth instructions and how i did everything if there is demand for it, otherwise everything like anything in the world now adays can be found on youtube

          Yesterday i got to building the front wheel "holder" where u slot the front wheel into so the whole bike doesnt move forward, used as many screws as possible and it seems relitivly bomb proof, the last thing i would want is to build a bike launcher that would shoot my bike off into my workshop and for all the gasoline to pour out, ignite, and then the whole garage would be ash, so keeping the bike steady and sturdy intop of both the dyno and my wooden pallets is priority number one
          alt text
          Oh yeah im also building everything ontop of wooden pallets, my first instinct was to weld a frame up from some square metal but i quickly realized that the price would skyrocket that way and me only being 17 with a very limited budget had to grab what i already had available to me, and it was these four wooden pallets, so far they work great and are really sturdy, im thinking of adding some wheels so i could eventually push the whole thing around in my garage. The pallets also keep everything really accesible and its really easy to spot if something goes loose, also alot of ratchet strap points.

          Today i got most of everything buttoned together, and it was my first time actually getting the bike up on everything.
          alt text
          I screwed the front wheel holder in place after taking some rough measuremtns of where it shiuld be to keep the rear wheel right over the rotor.

          Just came back in from my first testrun, im as happy as ever and honestly really proud that nothing broke or flew of in the garage, it did however open my eyes to some stuff i need to make it functional.
          Dynoing it on knobbies wont happen, the tiny test run i did everything shook like an earthquake, also realized the importance of an exhaust fan because the whole room was filled with smoke only from the tiny video ill link below, also thinking about adding some actual hooks into the pallets for even better ratchet points because i honestly cant be too safe with this.
          alt text
          Dont mind the mess
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          I dont know if u can post a video on here but here is the link to the first ever test run https://imgur.com/JT99Urx

          Bike isnt running perfect and it isnt really a big pull, its more just to make it a proof of concept even for myself, no computer or software plugged in either at the moment so didnt get any graphs or info yet, but its coming

          Now my dilemma is if i should try to do a burn out to get a diy flat dyno ready tire, buy some street tires for the rims and wheels i have currently or wait and buy some supermoto wheels when i find a good pair that fits my budget, its my dream to have a pair of supermotos on there, but its just expensive, especially with shipping from uk to sweden. But if u have a pair or know anyone thats selling or parting out their bike with sumos on it im interested for the right price

          sorry for yet another long post

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          • CalumC Offline
            CalumC Offline
            Calum
            wrote on last edited by
            #12

            Absolutely hilarious 😂 Great job on the dyno

            Always Originate, Never Pirate!

            A 1 Reply Last reply
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            • CalumC Calum

              Absolutely hilarious 😂 Great job on the dyno

              A Offline
              A Offline
              Arild
              wrote on last edited by
              #13

              @Calum

              Thanks mate, its pretty botched together and u can tell that its homemade, i like the charm it gives off, but if it will actually be funcitional in the end is something different, ill keep updating on here however and soon i hope to post some graphs aswell

              S 1 Reply Last reply
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              • A Arild

                @Calum

                Thanks mate, its pretty botched together and u can tell that its homemade, i like the charm it gives off, but if it will actually be funcitional in the end is something different, ill keep updating on here however and soon i hope to post some graphs aswell

                S Offline
                S Offline
                SpookDog
                wrote on last edited by
                #14

                @Arild
                Please, keep it coming. I Wish I had your technical know how now, let alone when I was your age. It’s good to see another generation with genuine passion and creativity...
                Plus it’s entertaining 🙂 ...

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                • S SpookDog

                  @Arild
                  Please, keep it coming. I Wish I had your technical know how now, let alone when I was your age. It’s good to see another generation with genuine passion and creativity...
                  Plus it’s entertaining 🙂 ...

                  A Offline
                  A Offline
                  Arild
                  wrote on last edited by
                  #15

                  @SpookDog
                  Ill keep updating man, me as much as anyone wants to see it finished and working, i managed to get it to read my bikes rpms today, tomorrow ill tackle the roller rpm and see if i can figure that out

                  S 1 Reply Last reply
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                  • A Arild

                    @SpookDog
                    Ill keep updating man, me as much as anyone wants to see it finished and working, i managed to get it to read my bikes rpms today, tomorrow ill tackle the roller rpm and see if i can figure that out

                    S Offline
                    S Offline
                    SpookDog
                    wrote on last edited by SpookDog
                    #16

                    @Arild
                    Don’t you really need another roller in front or behind the electric one? To stop the wheel from trying to climb off of the electric roller?
                    I think when there’s two the wheel just sits in between them. Especially if you can match the force/friction between them with a pulley or chain??...
                    Scratch that, the rollers have to turn in opposite directions. I can’t get my head around how you’d do that..

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                    • S SpookDog

                      @Arild
                      Don’t you really need another roller in front or behind the electric one? To stop the wheel from trying to climb off of the electric roller?
                      I think when there’s two the wheel just sits in between them. Especially if you can match the force/friction between them with a pulley or chain??...
                      Scratch that, the rollers have to turn in opposite directions. I can’t get my head around how you’d do that..

                      A Offline
                      A Offline
                      Arild
                      wrote on last edited by
                      #17

                      @SpookDog
                      Not really, if u look at production dynos its often just one roller, with the bike tied down and with the stop at the front it doesnt move, however ive been thinking and my conclusion is that it probably still wont work, seeing as the roller needs to be heavier, or larger diameter

                      This because the engine doesnt have the same resistance on the rollers as when its on ground, this causes the engine on the bike to rev to like 13k and the roller speeda up way too fast for accurate measurements i would think, havent tested that far yet however cause i had other stuff coming up

                      CalumC 1 Reply Last reply
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                      • A Arild

                        @SpookDog
                        Not really, if u look at production dynos its often just one roller, with the bike tied down and with the stop at the front it doesnt move, however ive been thinking and my conclusion is that it probably still wont work, seeing as the roller needs to be heavier, or larger diameter

                        This because the engine doesnt have the same resistance on the rollers as when its on ground, this causes the engine on the bike to rev to like 13k and the roller speeda up way too fast for accurate measurements i would think, havent tested that far yet however cause i had other stuff coming up

                        CalumC Offline
                        CalumC Offline
                        Calum
                        wrote on last edited by
                        #18

                        @Arild Keep us posted 😉

                        Always Originate, Never Pirate!

                        S 1 Reply Last reply
                        0
                        • CalumC Calum

                          @Arild Keep us posted 😉

                          S Offline
                          S Offline
                          SpookDog
                          wrote on last edited by
                          #19

                          Would weighting it with a flywheel help?...
                          I’m thinking dumbbell weight 😄 ...

                          Stevie WonderS 1 Reply Last reply
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                          • S SpookDog

                            Would weighting it with a flywheel help?...
                            I’m thinking dumbbell weight 😄 ...

                            Stevie WonderS Offline
                            Stevie WonderS Offline
                            Stevie Wonder
                            wrote on last edited by
                            #20

                            @SpookDog said in Engine tuning/ bike build:

                            Would weighting it with a flywheel help?...
                            I’m thinking dumbbell weight 😄 ...

                            I know nothing about dyno’s so bare with me here...
                            But wouldn’t altering the weight change the amount of resistance/force needed to move the roller in the first place thus altering readings more?

                            S 1 Reply Last reply
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                            • Stevie WonderS Stevie Wonder

                              @SpookDog said in Engine tuning/ bike build:

                              Would weighting it with a flywheel help?...
                              I’m thinking dumbbell weight 😄 ...

                              I know nothing about dyno’s so bare with me here...
                              But wouldn’t altering the weight change the amount of resistance/force needed to move the roller in the first place thus altering readings more?

                              S Offline
                              S Offline
                              SpookDog
                              wrote on last edited by
                              #21

                              @Stevie-Wonder
                              Long time no hear, bud!...
                              Yeah, but you’d want to try and match it to the weight of the bike and rider. Don’t get me wrong, I’m no expert on anything! My head just tells me that there needs to be some resistance otherwise it would be making revolutions and not much else?
                              How the feck you calibrate it I don’t know...

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                              • A Offline
                                A Offline
                                Arild
                                wrote on last edited by
                                #22

                                Small update, ive not really been in the garage since fall break ended but this is what ive done this weekend

                                I was curious if you could change the bushings in the clutch basket, since my engine is clanking alot and making wierd sounds and i somewhat remember the clutcj basket being somwhat loose when i put it in, so since i have another dtr basket laying in my garage, a broken one, i decided to see if it can be opened up and i was thinking if i could maybe cad up some bushings for the clutch in the bike.

                                alt text

                                This is what it looked like, and it can infact be redone if u have a sloppy basket and these bushings get worn out, the only thing is i think you would have to thread those three holes where there had previously been pins holding it all together.

                                I also decided to cad up an attachment to my dremel that i can use to port my barrel, since all 90 degree grinders are so expensive and ive seen other peopel doing similar things i decided to mock it up in cad.
                                this is what i came up with, still a rough idea tho

                                alt text

                                Might not look like anything, but it will be powered by a rubberband or something along those lines, i got this idea from two stroke stuffing on youtube on his video on a homemade 90 degree grinder https://www.youtube.com/watch?v=W6V5Piz_Uz8
                                Im scavenging parts from a 90 degree attachment i bought off of ebay that fits onto the dremel but it was too big to fit inside the bore

                                1 Reply Last reply
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                                • CalumC Offline
                                  CalumC Offline
                                  Calum
                                  wrote on last edited by
                                  #23

                                  Interesting to see the clutch basket split.

                                  I was looking at it the other day as it happens and was wondering what it looked like 😛

                                  Always Originate, Never Pirate!

                                  A 1 Reply Last reply
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                                  • CalumC Calum

                                    Interesting to see the clutch basket split.

                                    I was looking at it the other day as it happens and was wondering what it looked like 😛

                                    A Offline
                                    A Offline
                                    Arild
                                    wrote on last edited by
                                    #24

                                    @calum yeah i agree, i wanted to check if it was possible to change worn bushings and it looks like it is, however like i mentioned the real problem is putting it back together, my idea is to thread the holes and use some bolts and the best loctice there is but still id be somewhat worried of it coming loose

                                    Whenever my engine is being torn out for a rebuild ill probably look into rebuilding the current basket aswell since it was alot more loose than the broken one I split

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                                    • CalumC Offline
                                      CalumC Offline
                                      Calum
                                      wrote on last edited by
                                      #25

                                      Where are you getting the bushes from?

                                      Always Originate, Never Pirate!

                                      A 1 Reply Last reply
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                                      • CalumC Calum

                                        Where are you getting the bushes from?

                                        A Offline
                                        A Offline
                                        Arild
                                        wrote on last edited by
                                        #26

                                        @calum Id either take the ones from the broken basket since they seem pretty good, but im also thinking of designing a them in solidworks so whoever that needs them can just get them 3D printed, i however know nothing about 3d printing and im curious what the best plastic filament would be to use for something like that

                                        S 1 Reply Last reply
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                                        • A Arild

                                          @calum Id either take the ones from the broken basket since they seem pretty good, but im also thinking of designing a them in solidworks so whoever that needs them can just get them 3D printed, i however know nothing about 3d printing and im curious what the best plastic filament would be to use for something like that

                                          S Offline
                                          S Offline
                                          SpookDog
                                          wrote on last edited by SpookDog
                                          #27

                                          @arild
                                          Can you please post a pic of the under side of the cog piece?

                                          I think that the cog would have to be real sloppy loose to need new bushes...
                                          Also, I’d just rivet it back together like it was originally. Just use steel rod...

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