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How do I maximize top speed

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    #16
    My 52 38 front with 110 adaptor really threw off my chain line. It would be a lot better if i "lost" my 11 and fifteen and shimmed out the cassette away from the wheel making it an effective 6 speed. ??

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      #17
      Another thing is that i found that at 18mph i get lower watts at 52 to 18 than the 11. But at 30 mph the 11 is more efficient. The power range of this motor seems to lose at lower and higher motor rpms. Is this reasonable?

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        #18
        Back to civilization!

        My most used 26" wheel gearing is 44T front BBS02 tugging a 24T rear cog. If you search my post history you may find how I learned to rearrange cassette freewheels for only 3 cogs controlled by an old 3 speed front shifter on the LH grip. I use 14-24-32T cogs and that gives me plenty of gearing range for BBS02. But my most used cog is the 24T. Comfortable 20-22 MPH range there.

        For top speed, 44T-14T on 26" wheels allows my BBS02 to reach about 32MPH at max motor RPM. No need for more than that, right?

        Definitely stay away from 11T rear cogs. If you do the math you will find there's simply not enough room for bicycle chain to properly fit the 11T cog diameter.

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          #19
          Is this the bbshd? i actually think the BBSHD does better on smaller chain rings for top speed because it like to turn faster than it does even on the stock 46 tooth chainring. I think it can get bogged down with larger chain ring sizes especially if you are not inputting serious pedal power.

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            #20
            This bbs02.

            The 52 11 gives me 35mph. The 52 13 maxes out at 32.5. The 16 at 31.
            When i was using the stock 46 i could not get above 31 with the 46 11. Slower in other lower gears.
            Best i have done using only 750watts is 29 mph.
            I now have 38 and 52 on the front and 32 to 11 on the back. Just ordered a sturmey igh with cassette. The wide range of gear options should really be a test on being able to get full use out of available power.
            The batt man has been adjusted to the mm of tire diameter. The log read out is confirming.
            On the other extreme, to get highest watt per mile efficiency the 52 11 is not effective at lower speeds. Just makes heat.
            Mtn bike, touring tires, 20 pounds in panniers, 20 ah pf triangle. All on flat windless smooth asphalt
            I know everyone is saying lower gearing, spin fast. But it seems that the motor bbso2 looses its effective power as it approaches max rpm. Be interesti g to see power output vs rpm specs.

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              #21
              Ykick, very interesting. I do not need so many gears just wider range., i would like to use heavier chain (bmx) and cogs. Is this what you have been able to do?

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                #22
                The 20 to 22 mph range is good. I pushed a good 15 watt hour per mile doing that. Hard for me to do when i see a yellow light. That is with pedaling. My numbers on speed and gear are throttle only.

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                  #23
                  Read some more top speed with bbs02 on endless sphere. 40mph is easily achievable with right gearing. For any distance it is not sustainable without damaging motor. 1400 watts continuous is far above motor ratings. Illegal. Dangerous. Tires brakes etc all need attention. Losing my need for speed.

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                    #24
                    Originally posted by calfee20 View Post
                    I have often thought that the 30 mph figures that everyone bandies about is wishful thinking. My top speed is similar to yours. Then again I am 6'4" 280# and I have an upright riding style so I am about as aerodynamic as a sheet of plywood.
                    Well I take it back. I past the 30mph speed barrier the other day. I know the road was flat because I was on an old Railroad causeway with water on both sides. The only things different on my bike are the Big Apple tires , which I do feel that they roll easier, and a new 24 amp/hr. triangle from Luna. I may have had a bit of a tail wind though........calfee

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                    • ykick
                      ykick commented
                      Editing a comment
                      warmer weather = less voltage sag = more motor RPM

                    #25
                    Little off topic, but every time I read calfee20's statement " aerodynamic as a sheet of plywood" I laugh out loud. Thanks calfee, I needed that. Have a great day guys.......

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                    • ykick
                      ykick commented
                      Editing a comment
                      Agreed, the good man is a fun pleasure to read and converse with.

                    #26
                    Being a short 6' and down to 125 pounds, even getting low on the bars i can not exceed 38.5 mph.
                    Except downhill and wind at my back.

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                      #27
                      Here's what I believe are the watts / speed requirement for a medium-build downturn bars road rider:
                      Click image for larger version  Name:	speedpowergraph.jpg Views:	1 Size:	24.8 KB ID:	56548





                      If this is accurate, it may imply with a typical BBSHD / battery setup, us upright-sitting, pannier-equipped "barn doors" don't have much of a chance of exceeding much past, say, 32-33MPH, and the best we can do is squeezing out 1-2MPH refining our setups.

                      Or what I'm thinking here is pur-t-crap.
                      Last edited by ncrkd; 01-25-2018, 02:36 PM.
                      2nd build, 2018 Crust Scapegoat, BBS02 or BBSHD, Rohloff IGH
                      3rd build, 2018 Crust Evasion step-thru, BBS02, Nexus INTER-3 IGH
                      4th build, 2016 Salsa Marrakesh flatbar frameset, BBSHD, Alfine 8 IGH
                      5th build, 2019 Crust Evasion, BBSHD, Alfine 8 IGH
                      Other, Electronic throttle lock

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                        #28

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                          #29
                          Pretty much everything done to lower air resistance. Weight thinner tires. Maybe a gain of 5mph. But much better watt hour economy at higher speeds.

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                            #30
                            Originally posted by Gr8fun View Post
                            Pretty much everything done to lower air resistance. Weight thinner tires. Maybe a gain of 5mph. But much better watt hour economy at higher speeds.


                            I can see myself doing one of these. Maybe after the Luna cargo build. Next year? This guy has a great blog. Lots of pictures for the non readers out there. http://mrbill.homeip.net/hybridBike....rGoldRushBuild

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