Announcement

Collapse
No announcement yet.

Setting Toe-in / Toe-out on a Shadow handcycle??

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

    Setting Toe-in / Toe-out on a Shadow handcycle??

    Is the toe-in/out adjustable on the Shadow? maybe I am missing something because I measured the threaded inserts for wheel spacing and couldn't determine any variance. The spindle bore appears to be parallel with the threaded O.D.
    There is no indication of a datum/reference point.
    To adjust the toe the spindle bore should have an angle variance of a few minutes?
    Toe-out appears to be about 1cm. Sometimes it is a bugger doing these measurements on your todd - from a chair doesn't make it easier.
    Any help out there??

    #2
    Not sure what a "todd" is.
    Toe in/out is usually measured in degrees (or MM) perpendicular to frame center line.
    "Minutes" are used in navigation. I have forgotten how many feet are in 1 minute but 1 min in or out is an >EXTREMELY< large grossly visible amount.
    1 CM or 10 MM on one wheel is also excessive in my opinion. X 2 wheels = 20 MM toe out = a lot.
    I'm not an expert on these chairs but I can measure.
    Attack life, it's going to kill you anyway
    Steve Mcqueen (Mr Cool)

    Comment


      #3
      Hi Gearhead.
      on your todd
      On your own.

      To be clear, m reference to 'minutes of a degree' was the spindle bore relative to the receiver O.D.

      Minutes and seconds of degrees are incremental measurements that are not specific to navigation.
      Its all about scale, right?

      In reference to this Shadow that I have been told does not have a method/function to adjust Toe.

      If I was looking for a toe figure of 5mm over a wheel diameter of, lets say 70cm, then the spindle bore angle relative to the O.D would need to be less than 1 degree to achieve a + - range from 0 to 5mm of Toe.
      Its' late here and it is quicker to find a calculator.
      The answer is 0.41 degrees or 0 degrees 24' 36"
      Last edited by slow_runner; 28 Jun 2019, 9:16 AM.

      Comment


        #4
        If the axle setup is like most wheel chairs, the threaded inserts that the pip-pins ("axles" but not in my vocabulary!) are inserted, are at some angle to the axle tube that connects them, and the left and right threaded receivers fixed so that they both have the same angularity to the axle tube.
        This angularity is the camber of the wheels, often 2*negative which means the top of the wheel is inward relative to the bottom.

        Usually toe is adjusted by rotating the axle tube slightly, and the desired toe is -0-, meaning the wheels are pointing straight ahead and parallel.
        And, it sucks to try to measure it from a wheelchair! It's hard enough for the able. You need to measure the distance at the same height of both wheels fore and aft.
        If you can put the thing up on a table, it becomes much easier, but remember that all wheels need to be on the same plane, otherwise the toe will not be the same as in use.
        Having a second set of hands is helpful for the measuring, one person per side.

        Question: "If I was looking for a toe figure of 5mm over a wheel diameter of, lets say 70cm,"

        Is that what you want the toe-in to be or is that what your measurement is?
        Not to further stir the pot, but what I wrote above doesn't account for any runout or bends in the wheel. If you spin the tires and there is any
        significant runout, you can counter it by marking the tires/wheel rims where you take a rear measurement and then roll the thing forward until the marks are at the same height and taking the front measurement.
        And, to stir the pot even further, I wonder if zero toe is 100% correct if you have negative camber!
        My experience with low power race cars suggests that you may actually want some toe-out (frts farther apart) to achieve minimum tire-scrub/rolling resistance! (based on coast down testing with 8" wide treads and -3.75* camber)

        And, I get what you mean about ' and "! Many European manufacturers call for specs like -47' camber! I prefer decimal degrees!

        Last edited by pfcs49; 28 Jun 2019, 12:42 PM.
        69yo male T12 complete since 1995
        NW NJ

        Comment


          #5
          Top End used to make a gauge that slide in and out to get the distance between the wheels. First I'd take a measurement by sliding the gauge between of the rear of the wheel and tightening down the slide then measure the front. Would make the changes on both until they matched up front and rear. I'd make the changes with the camber bar loosened just enough to twist it. once done, I'd tighten up the camber bar and recheck the measurement.

          To do manually adjust for a 24 inch wheel. Measure up 12 inches on both wheels front and back and mark the spots. Then measure between the wheels front and back at those spots. Check the differences and make the adjustment until both are the same. Tilite has mitered flat areas on the sides of their axle inserts. If you chair has those, find a flat spot of ground and use a square to see that the flat area lines up with no space showing between the edge of the square and edge of mitered flat area on the axle insert. Simple as that. I wouldn't put the brakes on doing this because it may make the wheels splay out abit because of the tension of the brake against the tire.

          Degree of camber has no bearing with the measuring as long as the front and rear are the same, toe-in/out is correct.

          Comment


            #6
            "Top End used to make a gauge that slide in and out to get the distance between the wheels."

            I've clipped two framing squares together to do this. If your goal is -0- toe, using these short ones that are 8" high works, but if you want a different value you'll need to factor in the height difference.
            Attached Files
            69yo male T12 complete since 1995
            NW NJ

            Comment


              #7
              The ingenuity of so many on this forum is incredible. There ya a go, a ready made alignment gauge using two squares.

              Comment


                #8
                I enjoy reading these post even though many times it just reveals how much I do not know... lol

                Comment


                  #9
                  Originally posted by pfcs49 View Post
                  .......Having a second set of hands is helpful for the measuring, one person per side.
                  Question: "If I was looking for a toe figure of 5mm over a wheel diameter of, lets say 70cm,"
                  Is that what you want the toe-in to be or is that what your measurement is?
                  And, to stir the pot even further, I wonder if zero toe is 100% correct if you have negative camber!
                  And, I get what you mean about ' and "! Many European manufacturers call for specs like -47' camber! I prefer decimal degrees!
                  5mm Toe was just a nominated number. When I first measured at the rim using a tape and guestimate system I had 1cm positive Toe. Not too ideal.
                  With so much camber I think that neutral Toe or very minimal positive would be optimum. My thinking is that the wheels are rear mount and there is begger all tyre footprint on the pavement so less directional forces. just an instinctive feeling and maybe off beam??

                  The wheels are even spoked so I selected 2 of the outer opposing set and to identify them as pairs, I tagged them with a small piece of masking tape each.
                  Rolled the trike forward until I matched each wheel forward spoke at near centre (32cm height). My good neighbour sat on it to give some ballast and I laid the tape measure between the front spokes abutting the rim then read off at the inner side of the tape (clear??).
                  Then did the same at the rear. 1mm negative differential.
                  Rolled the chair forward and reset the spoke position. 3mm positive differential.
                  I am happy with that although I will bugger about with this method a bit more.
                  I have a couple of string line levels and am thinking that if I lay one on the selected spoke and roll till it reads level, I will have an ideal constant reference at true centre, every time.
                  I am going to try that idea tomorrow and I will post some pics if I remember.
                  The rims are running very true. There is some run out but naff all to be concerned with given this is a chair and not a track racing machine.
                  Thanks for all the suggestions; I think we all are learning something. I am.

                  I wonder why Quickie did not make those threaded inserts with a degree difference in the axial plane? Maybe they judged their jigging and manufacturing tolerances to be near enough on?
                  From the results from my old early example it would appear to be the case.

                  Comment


                    #10
                    I encourage you to do some coasting tests with different toe settings, first -0-, then a little toe out, and see if it rolls farther one way or the other.
                    And, if it has less resistance/rolls farther with toe out, then experiment to find the optimum setting.
                    You'll need to find a gentle slope that flattens out so the speed and length of the runs is manageable. Do several runs with each change to confirm your measurements.

                    Now that you've optimized the alignment, let's work on aerodynamics (for this we'll need a much bigger hill)
                    69yo male T12 complete since 1995
                    NW NJ

                    Comment


                      #11
                      I encourage you to do some coasting tests with different toe settings,
                      Good advice PF but there appears to be no facility to adjust the Toe setting on this machine. The variance I am getting is due to existing fit tolerances and my current method and the ability to repeat with any real accuracy.
                      The idea of using the line level should afford better repeatability. We will see...
                      In respect to the aerodynamics I would need to sit side saddle to afford any improvement there, or wear a slip suit
                      I am looking forward to getting out and about on it

                      Comment


                        #12
                        There's no way to rotate the axle/camber tube to adjust toe? (assuming it has some camber)

                        The comment about aero drag was a little facetious but illustrates how small amounts of drag can be observed using coast-down runs. Using a full sized (race?) car is more productive perhaps.
                        69yo male T12 complete since 1995
                        NW NJ

                        Comment


                          #13
                          Originally posted by pfcs49 View Post
                          There's no way to rotate the axle/camber tube to adjust toe? (assuming it has some camber)

                          The comment about aero drag was a little facetious but illustrates how small amounts of drag can be observed using coast-down runs. Using a full sized (race?) car is more productive perhaps.
                          Yes, that is correct, there is no method of adjusting Toe. Or none that I can see.
                          I set it up on level ground and planted a willing volunteer in the drivers seat. Then set the forward spokes at level using the string level - a bit hairy because the hooks had been removed previously.
                          Any hoo. The first reading gave 720mm front and 724mm rear (spoke to spoke withe the tape abutting the rim).
                          I rolled the trike forward one revolution and remeasured.
                          This time the readings were 722mm front and 723mm rear; near enough for me.

                          facetious? Yeah I got that one And you got mine?? All good.
                          The upside of a decent width profile is any tail wind will assist and that has to be a positive, right?
                          Attached Files
                          Last edited by slow_runner; 30 Jun 2019, 4:17 AM.

                          Comment


                            #14
                            The differences you got was because you are using a quick release hub. They have to be a bit loose for the button to work. hence the different measurements, really small difference.. Depending how old this bike is, the old early Quickies didn't have adjustable camber because camber was just being introduced to the wheelchair world. If your axle sleeves have a flat spot on each side, that's how you adjust the camber. One wheel at a time. Once the adjustable camber bar came out then both wheels would adjust jointly.

                            It was a real drag trying to adjust separate wheel cambered bikes back then. Especially when we were using 16 and 20o cambers. Would take hours sometimes getting each wheel right. You seem really close and well within the range for toe. Big plus there. Are those high pressure tires( around 100 lbs.)? High pressure tires make a big difference in rolling resistance. I pretty sure you know that though.

                            Comment


                              #15
                              Originally posted by Patrick Madsen View Post
                              The differences you got was because you are using a quick release hub. They have to be a bit loose for the button to work. hence the different measurements, really small difference.. Depending how old this bike is, the old early Quickies didn't have adjustable camber because camber was just being introduced to the wheelchair world. If your axle sleeves have a flat spot on each side, that's how you adjust the camber. One wheel at a time. Once the adjustable camber bar came out then both wheels would adjust jointly.

                              It was a real drag trying to adjust separate wheel cambered bikes back then. Especially when we were using 16 and 20o cambers. Would take hours sometimes getting each wheel right. You seem really close and well within the range for toe. Big plus there. Are those high pressure tires( around 100 lbs.)? High pressure tires make a big difference in rolling resistance. I pretty sure you know that though.
                              Gidday Patrick
                              Yes, there is a bit of accumulative movement with QR and I imagine, maybe some attributed to spoke flex.
                              The sleeves do have flats but I believe that they are for aiding in adjustment of the wheel track.
                              I had measured the threaded axle sleeves earlier to determine if there was any axial difference (angle) What I detected was naff all that could be attributed to any design for Toe adjustment. Having said that, maybe I will revisit it, mark where any difference is and see if rotating the sleeves has any marked effect.
                              Add: there is no mention in the online manual for Toe adjustment either. Unlike the Top End Excelerator manual which explains in depth.
                              I would be interested to see an adjustable camber bar for the Shadow. Did they straighten the axle tube as per the Top End?

                              The tyres are bog standard 65 p.s.i max that will make do until I need to replace. I do have a Marathon that could be substituted but my intention at this point is to use these until they require replacing. A good plan or not??
                              Last edited by slow_runner; 30 Jun 2019, 5:29 AM.

                              Comment

                              Working...
                              X