Announcement

Collapse
No announcement yet.

rear hub, internal gear options.

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    #31
    Yesterday I found myself passing a car that was going too slow to my liking, on a slight downgrade, 39 mph! And I could still feel resistance/keep up when pedaling! The day before that I rode the "Boundry Trail", a super steep and rocky dirt bike trail nearby, which involves mostly trials bike type riding: 3 or 4 mph, standing on the pedals, and picking your way through and over rocks the size of watermelons in places, mostly cantaloped sized! This requires a very low gear of course. I am really enjoying, and using, the extreme spread I have with the Rohloff, just what I had hoped, fast AND slow. Coming up on 500 miles of hard riding on it, mostly trail riding, so far so good.

    Comment


      #32
      Originally posted by spinningmagnets View Post
      The middle gear on the Sturmey 3-speed and 5-speed are as strong as anything made in any IGH, due to the way it's constructed. The middle gear locks the input sprocket carrier to the shell, and doesn't actually pass any power through any gears. It's 1:1...

      Since the shells are similar in size, then we are limited in the size of the gears inside. In a 3-speed, first and third gear are pretty strong, but nowhere as strong as 2nd gear.
      What You Said:
      https://youtu.be/K3QJTTcDXJo
      I thought Fat Tire Bikes were a kinda new thing. <]:~)
      Last edited by Reddy_Kilowatt; 09-20-2016, 11:37 AM.

      Comment


        #33
        I liked the video you posted. From the video you posted there is only one set of gears and a lot of wasted space on the left side of the hub. There should be plenty of room for additional gears in this wasted space. I really don't know I need to take one apart. Now that you have me thinking my father had a 3 speed and I don't know where it is. I will have to look around the barn.

        Comment


        • calfee20
          calfee20 commented
          Editing a comment
          Well it is not in the barn. He was making garden carts with bike wheels for my sister and a few bikes got scrapped. I found a dozen wheels laying around but no 3 speed. LOL maybe I should start visiting the dump............calfee

        #34
        Calfree20, "THIS HUB'S FOR YOU".
        i found that old 3 Speed you were looking for, so let's take it apart.

        https://youtu.be/e2YDcLF_CNI

        Comment


          #35
          The same thing happened with my bbs02 the derailleur bracket got ripped off when the derailleur got caught in the spokes. I have an Alfine 8 IGH on order and I'm hoping it will solve all my gear shifting woes and I finally get a smooth ride.

          Comment


            #36
            There are SA 3 speeds with derailler hubs. The 3 speed IGH replaces the front triple chainring basically.
            http://www.sturmey-archer.com/en/pro.../cs-rk3-silver
            Surly makes some tough derailer splined cogs. Supposedly they can be shifted, but I imagine it would be more like choosing a speed range, than a transmission type of shifting.
            https://www.modernbike.com/surly-sin...gaAnUfEALw_wcB
            You could probably make a 9, 12, or15 speed setup out of these.
            The Sheldon Brown Gear Calculator has IGH hubs in it so you can see what cogs will suite your purpose.
            https://www.sheldonbrown.com/gear-calc.html
            Last edited by Retrorockit; 08-24-2019, 04:06 AM.

            Comment


              #37
              Originally posted by DukeOfWellington View Post
              The same thing happened with my bbs02 the derailleur bracket got ripped off when the derailleur got caught in the spokes. I have an Alfine 8 IGH on order and I'm hoping it will solve all my gear shifting woes and I finally get a smooth ride.
              I have a S-A hybrid drive and an Alfine 8. They are both very nice but I will give the edge to the Alfine.

              Comment


              • Retrorockit
                Retrorockit commented
                Editing a comment
                I have a Nexus 8, and a 50x 11-40 8 speed Rapid Rise derailer.I like them both .But with an 11-34 casette the S-A hybrid has the abilty to almost equal the gear range of the Rohloff.
                Last edited by Retrorockit; 08-24-2019, 05:49 AM.

              #38
              Hi Folks, I'm soliciting help choosing gearing for a 3-speed IGH...

              I'm planning to do a 500W continuous, 750+W peak mid drive conversion. Either the TSDZ2 or the just-being-released-with-steel-output-gear Bafang M600 (MM G521.500C) paired to a 14-series (52V) battery pack. 650b (27.5+) x 2.0" tires... likely Schwalbe Big Ben Plus.

              I would like help choosing my gear ratios. Alas, I've been spoiled by the 8-speed Shimano Alfine IGH and Gates belt drive on my 4-year old Faraday Porteur (Faraday rented space from my company, Mission Motors, when they were still a Kickstarter). Never needed a single bit of drivetrain maintenance in 4 years...

              So, I'm choosing between the 50T, 55T, or 60T Gates front sprocket and the smallest allowable 22T gates rear cog. My goal is to be able to cruise at 28 mph at a reasonable 75-80 RPM pedaling cadence. With the mid-drive's power, I don't think I'll need more than 3 gears, so I'd rather save the weight, cost and reliability risk and package the lightweight, cheap, robust Shimano Nexus 3. Top gear on the Nexus 3 is 1.36x.

              Which front Gates sprocket would you recommend between 50/55/60 teeth? I have done the calcs of human pedaling cadence with the aforementioned tire diameter as follows:
              75 RPM pedaling cadence
              50T:22T = 18.6 mph
              55T:22T = 20.4 mph
              60T:22T = 22.3 mph

              However, I know that the mid drive will be adding torque, so the rear wheel will be spinning faster than just a human pedaling cadence. I don't know how to factor that in. Or is it a bad idea to run the system faster than expected human pedaling cadence because the "feel" of pedaling will be incorrect?

              Thanks for feedback!

              Comment


                #39
                Sheldon Browns gear calculator can let you try out as many gearing setups as you like. Several at once in fact. For gear units select the cadence you want. Put in the teeth of the belt sprockets as chainrings up to 3 sizes. then your 22T cog. Select the desired IGH and you will get a speed chart for that cadence with those gear ratios. You can add many other rear cogs also.
                https://www.sheldonbrown.com/gear-calc.html
                TSDZ2 has serious overheating issues. There is work being done on it here. But no final solution.
                https://endless-sphere.com/forums/vi...788&start=5500
                It's popular in the 350W European market. But lots of modding, repair, and upgrading needed.Very high maintenance.I would go with Bafang.
                If you can pedal at 90rpm which is not that hard on an ebike 60x22 gives 27.6mph.
                Shimano has a new 5 speed E bike rated IGH out in Japan and Europe. It's not in the gear calculator yet. 1:1 first gear.
                https://bike.shimano.com/en-EU/produ...-C7000-5D.html

                The only thing that costs more than doing it righ the first time, is doing it right the 2nd time.

                Comment


                  #40
                  I just saw a post at Endless sphere that the TSDZ2 can only handle 8-10A. continuos. 18A. is momentary and requires soldering a thermal sensor instead of a throttle, and open source firmware, and aftermarket display, to regulate output based on temperature. BBSHD =30A. continuos.
                  Basically it's a 350W 20mph mptor.

                  Comment


                    #41
                    Originally posted by Retrorockit View Post
                    I just saw a post at Endless sphere that the TSDZ2 can only handle 8-10A. continuos. 18A. is momentary and requires soldering a thermal sensor instead of a throttle, and open source firmware, and aftermarket display, to regulate output based on temperature. BBSHD =30A. continuos.
                    Basically it's a 350W 20mph mptor.
                    Thanks Retro for this update - kinda wondered after seeing the TSDZ2 motor "meat", as it were.

                    Damn, I'm hoping the BBS02/BBSHD motors aren't the end of the line / as good as it gets.
                    2nd build, 2018 Crust Scapegoat, BBS02 or BBSHD, Rohloff IGH
                    3rd build, 2018 Crust Evasion step-thru, BBS02, Shimano Nexus INTER-3 IGH
                    4th build, 2016 Salsa Marrakesh flatbar frameset, BBSHD, Alfine 8 IGH
                    Electronic throttle lock

                    Visit the forum knowledge base

                    Comment


                      #42
                      There's a Bafang M600. but IDK anything about it. If you want to go 30mph and not spend time fixing anything except driveline expendables BBSHD is hard to beat. ( @ 1500W the entire driveline becomes expendable, but 750W etc. are options).

                      Comment


                        #43
                        IF there was a industry motor mounting standard, I'd be a lot less hesitant of going that route - there isn't even a standard for the same vendor!
                        2nd build, 2018 Crust Scapegoat, BBS02 or BBSHD, Rohloff IGH
                        3rd build, 2018 Crust Evasion step-thru, BBS02, Shimano Nexus INTER-3 IGH
                        4th build, 2016 Salsa Marrakesh flatbar frameset, BBSHD, Alfine 8 IGH
                        Electronic throttle lock

                        Visit the forum knowledge base

                        Comment


                          #44
                          Maybe not quite on topic, but I don't get why people are confused about letting go off the throttle (or stop pedaling) while shifting. When you ride a car (or a motorbike) you also let go off the gas pedal (automatic) or disengage the motor from the transmission (manul), right?

                          Comment


                          • Retrorockit
                            Retrorockit commented
                            Editing a comment
                            Using the throttle can work if you"re on 0 level assist. If you're on one of the higher assist levels as long as the pedals are turning at all the assist is there. There is also a 1/4 turn delay to resume power. The gear interrupt device blips the brake interrupt switch circuit each shift avoiding the need to stop pedalling completely, and wait 1/4 turn for power to return. PAS systems are better in this regard, but IDK of one with the power and strength of a Bafang mid drive.

                          • toro1978
                            toro1978 commented
                            Editing a comment
                            I think my confusion comes from the fact that I haven't been riding a bike derailers in years. So I completely forgot you need the cranks turning to in order shift. I assume that is why if one is used to deraillers and not IGH it might be initially weird to them having to disengage the motor and the "transmission" before a gear change.

                          #45
                          Thanks Retro for your feedback. Of course I've used sheldon brown gear calc. But I'm asking about something specific. From what I understand, there is a one way clutch (i.e. sprag clutch or similar) between the mid drive and the pedal cranks. So, the mid drive can be spinning at 90 RPM while I am pedaling at 75 RPM. I have never ridden a mid drive, so I am asking the folks on this forum if that is indeed the case. And if it is indeed the case, what does pedaling feel like when you are pedaling at a slower RPM than the mid drive is cranking the drivetrain/rear wheel? Will the "feel" of pedaling be incorrect? Will it feel like I am pedaling against no resistance... kind of like pedaling in 1st gear when you are biking down a hill where you should be in 5th gear? Or does it still feel like you get some resistance and each pedal revolution is applying a reasonable amount of torque into the system?

                          Comment

                          Working...
                          X