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Front freewheel mod. (zip tie mod for hubmotors?)

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    Front freewheel mod. (zip tie mod for hubmotors?)

    This is a spinoff of the Mid Drive Cassette Zip tie Mod thread which is pretty much complete for BBSHD etc..
    This is how to do the front freewheel mod om bikes that don't already have one. Maybe a hub motor bike, an urban bike, or just to get another bike to shift the same as a zip tied Ebike.
    I've ordered a bunch of parts to look into this. Some of it is clunky old Cyclone or Sick Bike Parts surplus. But some of it is nice tandem and BMX / Trials bike stuff. Some of it's coming from England so I won't start until that gets here. It's sized for pedal bikes, not monster motor conversions so probably what will actually get used for this. I do have a White Industries HD BMX racing freewheel in a mid drive format. It might be the difference between success and failure on this project.



    Here is the very expensive, noisy as hell German version which comes with...........a zip tie!
    Integrated ratchet mechanism Ratchet system with 47 engagement points Highly optimized construction for hardcore applications … Continued
    Last edited by Retrorockit; 10-09-2023, 05:52 AM.

    #2
    These are the cranks I'm planning on using.
    https://www.sjscycles.co.uk/cranks/shun-alloy-104-pcd-4arm-freewheeling-cranks-170-mm-silver/?sessionid=0196be8f16b184815594deda5d10c0e92e8f03f e&geoc=US&changecurrency=USD

    This is the HD freewheel. I won't know if the freewheels are interchangeable until I get them both here.

    I know they will fit on the crank, but IDK if the chain ring adapter will swap over.

    I willl probably include the chain guide partly so I can swap derailleurs around without worrying about chain control, and partly to keep any side loads off of the freewheel since they only have one bearing.

    Parts for it.
    Last edited by Retrorockit; 09-22-2023, 07:15 AM.

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      #3
      I got the tandem stoker freewheel cranks from UK. Weighed them against some XT Hollowforged cranks and the cranks came in within 20g. each and they look nice too. Toss in a steel front freewheel and weight goes up over 700g. The generic freewheel they come with isn't sealed and oozes grease all over the place, so it won't even get at tryout. The White Industries sealed BMX racing part from Sick Bike Parts (Ebay surplus) looks like the way to go. The 104BCD adapter has the shoulder for the Shimano outer chainring and not the aftermarket ones that fit in the mid position. But it was designed for 2 rings on the tandems so I can go either way, or use the Sick Bike Parts 110bcd adapter for other options. But the tandem parts look just about like the XT parts they replace, and take the same Shimano chain rings that I already have.
      Last edited by Retrorockit; 10-06-2023, 05:18 AM.

      Comment


      • Retrorockit
        Retrorockit commented
        Editing a comment
        White Industries still offers the E Bike freewheels. The price is the same as other "special" versions from them.Definitely not cheap. I found some NOS on Ebay for 50%.off.

        The SJS stoker cranks come with a generic Dicta freewheel included.So there is probably no real need to do this.
        Then there's this.
        "Really... just get WI and don't look back. I've had three which have been 100% maintenance and trouble free until the cog wore out. By the time you factor in replacing multiple MX30's over the same time it works out about the same/cheaper. And a handy side benefit is the Death Swarm Of Bees click is a great way to encourage peds not to step out in front of you."
        The White Freewheel is obviously noisy. I have mixed feelings about this. it will be quiet unless you stop pedaling. That would be every shift with the front freewheel mod. But it will be in time with pedal speed, not road speed. So the sound may be useful to know which gear is the one you need to be in.
        I've heard that if you pack them with grease they quiet down.
        Last edited by Retrorockit; 10-06-2023, 06:28 AM.

      #4
      I tried a mockup of the toothed idler chain guide (https://electricbike.com/forum/forum...5t-chain-guide) using an old prototype I had laying around. It had interference with a water bottle boss on the seat tube, so I'll have to make another offset/ angled one.
      The idler chain guide is from the zip tie mod. It deals with any slack in the top of the chain form the zip tie/ friction drive freehub mod. But in this case also feeds the chain straight onto the chainring like a single speed, which is where these HD BMX freewheels come from. SJS ( the vendors of the stoker cranks) say only for IGH bikes. So I think the chain guide may be needed for that even if the derailleur provides enough chain tension.
      I've ordered a few cheap 110BCD chain rings from China. 42,44,46t. I haven't ridden the pedal bike in so long IDK what gearing I actually need at 70yo. When I figure that out it will probably get a Surly SS chain ring.
      I've been trying to get some photos up. I thought it was because my SSD drive was full. But I fixed that and still no pics.

      Comment


        #5
        This is what the stoker crank, and the White Industries freewheel look like with the Shimano XT 44t chain ring.
        Click image for larger version  Name:	image.png Views:	0 Size:	1.27 MB ID:	164973Notice the BB lockring, the freewheel uses the same thread. The XT 32t middle ​​chain ring fits also. The stoker setup is intended for 2 chain rings. But I will be using the single 5x110BCD adapter from Sick Bike Parts for a 1x setup. I don't have any 110BCD chain rings yet.
        There are similar cranks available from Trials bike suppliers, and simialr HD freewheels with insane numbers of ratchet counts. This one is 36 clicks per revolution. Some are 72, 108, or even higher. This one is a BMX rated 36 position 3 pawl unit. It was intended for Cyclone type Ebike kits. Some trials bike stuff has a 4 bolt freewheel pattern/
        Last edited by Retrorockit; 10-07-2023, 08:10 PM.

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          #6
          My 110 BCD chain rings are taking longer than expected to arrive. But they're in country so they should arrive pretty soon. Looking online and at White Ind. website it looked like the ENO freewheels ahd just one bearing. Which would be OK for single speed. But The bearing on the rear is clearly marked 6808 which should have a red losk ring from White, But mine has blue, whic is for the smaller 6708 bearing. So I got curious and pulled the lock ring off, and instead of the expected seal, found a 6708 bearing. So this one has 2 bearings. They don't mention that on their website. So this may have more potential than I thought.

          Comment


          • Retrorockit
            Retrorockit commented
            Editing a comment
            I also found a 40% stronger 6808 LLU bearing with full bearings and no separators.

          • Retrorockit
            Retrorockit commented
            Editing a comment
            I was wrong. It doesn't have 2 bearings. It has the expected 6708 bearin for the blue freewheel. They used an Enduro 6808 bearing seal w/o the bearing to seal the back. So it looked like it had 2 bearings, but has just one. I can make it work OK, It just limits some options.

          #7
          The chain rings arrived and I got it together. The swap to the square taper BB was straight forward. The White freewheel needs to be all the way onto the crank with a BB lockring for a spacer. During the test ride I could feel it getting turned tighter onto the crank. No idea if it's bottomed out on the end of the threads, or the spacer. But it wouldn't clear unless it was all the way in. The chain line is about the same. A 46t ring clears the frame, maybe a 48 would too, but 46x11 top gear seems like enough for me. First test drive seemed strange, then I realized i forgot to add the zip tie to lock out the rear freewheel. LOL.
          I did that and it;s working now. Clutch derailleur, Wide Narrow ring seem to be enough.The clicking of the White Industries freewheel lets you know when you need to shift. the sound gets faster or slower than normal if you need to shift. TBH I can't say this is a big deal on the pedal bike.. But now both bikes shift the same way. Now there's a way to add this to a hub motor Ebike if anybody wants to. The Chinese Wide Narrow chain rings look and work OK so far. But the Chinese tandem crank has a little wobble in it. I spin the chain ring on the freewheel and it runs straight, tun the cranks and there's little wobble. Not enough to hurt anything but not up to Shimano standards. usually it's the freewheel that wobbles! I'll add the chain guide even though the chain isn't dropping off because the frrewheel isn't designed for angled loads. So I'll get he chain running stright onto the chain ring.

          Comment


            #8
            I played around with gearing. I'll probably end up at 42t. But I put 46t back on to dial in the chainline. Dead striaght in 6th gear. I don't have the right spacer Behind the cassette om the Mavic hub, so that my change again later. I added the 15t recumbent drive side idler as a chain guide. It's to send the chain in straight onto the chain ring like a single speed, but on my Ebike it prevents all kinds of mayhem. The 11s MTB cassette is just a little wider than 9-10s. Just enough that the guide is alittle noisy in the lowest gear. I don't use that very much. It's the chain bending around the sidewalls of the idler. A lot of stuff is a tight fit on this. Freewheel is about 1mm from the 73mm BB, The 46t ring is close to the frame, and the idler is almost touching it's bracket. But I like it when a bunch of mismatched parts like this work together. Much better than when they don't.
            The 44t ring won't work right now. A water bottle boss is in the way. I'll make a custom bracket later.​

            Comment


            • Retrorockit
              Retrorockit commented
              Editing a comment
              This is what I like about the old 3x8-9 MTB format. Just about any bicycle part you can think of will fit.

            • Retrorockit
              Retrorockit commented
              Editing a comment
              I'm waiting on some cassette and freewheel shims to tidy up the chain line. My Mavic XC hubs have a road 11s spline and need a spacer. The BB Lockring for the freewheel didn't stay locked under pedaling pressure. So I need to shim that solid. I can countersink the Allen bolts on the idler bracket to get some space there.

            #9
            I played around with some 1mm BB spacers behind the freewheel. There wasn't room to add one. So on a 73mm x 123mm BB, the SJS/Thorn tandem freewheel crank, and White ENO freewheel are bolt on as is, and not much room to adjust. I used the Chrome SJS BB lockring between the freewheel and the cranks. It's in there as a a spacer and not an adjuster. The spacer is bottomed out on the crank arm, the freewheel is bottomed out on the spacer. I took it apart and put it back together, so it doesn't seem like the thread is damaged from the freewheel going on too far. Truck Mechanic tools came in handy to get it apart though. Like freewheels everywhere they do get tight.
            I got the official Shimano 11 speed low gear cassette spacer for 11s MTB casette on HG11 road hubs (My Mavics) So I will gain some chain line at the cassette. I dropped down to a 42t chain ring to get rid of the humongous 11-51t casette. When this was my primary street bicycle I ran a 48t ring on 3x8.
            46t fits 1x11. But I think 42t is about right for my advancing age. If i'me in a hurry I take the Ebike. So any chainline adjustment will be with washers at the chainring, or freewheel adapter plate.
            I may end up not needing any washers. It's pretty close the way it is. Of course this is a 2004 3x 8/9 MTB so every thing is pretty much made to fit that format.
            I tried to make it complicated, but it really was just a bolt on thing.

            Comment


              #10
              I put this together and rode it today. I test fitted an 11-51T cassette ans 46t chain ring to see what would fit and work. But the steel cassette was very heavy and not appropriate for a lightweight XC bike. I went with an 11-40 Prestacycle monoblock cassette (the 11-40t has 2 large alloy cogs, and the rest steel block). I used this because it can be found for about 1/2 of it's list price, and my bike happened to have the uhusual HG11 road freehub spline on the Mavic hubs. So don't try this at home.
              I went with a 42t chain ring. The single bearing ENO freewheel which has a reputation for strength in BMX racing.
              The 15t idler chain guide form Terra Cycle to guide the chain onto the chain ring straight like a single speed.
              It works as expected. I can up or downshift any time the bike is moving. The sound from the freewheel can let you know when you're in the right gear, or need to shift.
              I did open up the Cyclone freewheel Luna is selling on closeout. It has 2 angular race ball bearings, so may not need a chain guide. But it's not the sealed Chromoly Nickel plated workhorse the ENO is.
              I really want 175mm cranks for this, so I will probably try that one w/o the chain guide at some point. But no ENO, and no chain recumbent guide really changes the price point on this mod. Ut also saves some weight and looks more like an XC race bike.

              Comment


                #11
                Since this isn't Ebike specific i'm continuing this at MTBR.

                I'll mostly be looking at other options for the freewheel. The $150 ENO Ebike freewheel is back on Ebay for $75 NOS

                Comment


                  #12
                  I haven't updated this here for a while. I ended up with a 42t chainring, and an 11-40t Preastcycle monoblock cassette (the 2 biggect cogs in this size are alloy on a 2nd block). About 400g. less than the Shimano M5100 discus. So My chainring options are 46t to 36t. The cassette can go up to 51t.
                  I rode it around. it shifts the same as my Ebike so that problem is solved. The ENO freewheel clicks at pedal speed when coasting (Shifts w/o pedaling now). The sound is useful for knowing which gear is the right one to shift into. Kind of like a Moto or sports car shifting by ear.
                  But I couldn't leave well enough alone. Looking at all the trials cranks and freewheels (some will fit this) i found that ENO offers a 72 click trials freewheel. All the kool BMX kids have one.
                  So I bought the 6 pawl trials driver assembly to see if it would fit inside the Ebike freewheel. White avoids saying outright if this will work or not. But my mechanical intuition s better than most.
                  So now I have the worlds only ENO Ebike/Trials Front Freewheel. Consistent 5* engagement at the pedals.
                  So it's doing all the Front Freewheel stuff. Up and down shifting, any gear any speed pedaling or not.
                  if you level the cranks for ground clearance and toss it into low gear the derailleur cage comes up too.

                  Comment


                    #13
                    A short vid. of this mod.
                    Last edited by Retrorockit; 12-18-2023, 11:45 AM.

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