QS 3000 138 motor bike installation generalized

DingusMcGee

10 kW
Joined
Feb 23, 2015
Messages
944
Location
Laramie, WY
Having completed such a task, some insights are worth passing on to new enthusiasts for when they begin the same task.

Here is a pic of my finished product:

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Building the motorframe:


Drive train possibilities:


No more writing tonight -- tired but stay tuned.

See a little bit more of this installation that was posted on page 139 of the thread,"new Cyclone 3000w mid- drive kit?"
 
HI Lars,

Thanks very much for your contributions to the thread on the Votol Em 100 & EM 150 controllers. They aided me in getting this system up and quickly.

'You say, "...that front wheel will like to fly."

Yes, the position one has using an ordinary bike seat location is too far back to keep the front from flying.
 
The QS 3000 138 motor came with a type 428 14T motor sprocket 20mm outer 17mm inner with 6 splines was not available in the USA in that size as a motor cycle part. I sent a request to QS-motor.com and got a reply within 12 hrs.

The output shaft measures:IMG_0679.PNG

Here is the QS reply
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So Robert Chen of QS will likely be willing to supply these sizes of motor sprockets.

I have since found this link that has the 20mm type 428 hub for the QS 3000 and others:

https://www.aliexpress.com/popular/420-chain-sprocket.html?spm=a2g0o.detail.1000012.11.109c75ceUNeTLo

Better Yet:

on eBay use the search words "front sprocket motorcycle 20mm". The delivery will be much sooner than AliExpress.
 
We are talking a mid-drive installation for the QS 3000. The motor mounted either in front of the bottom bracket or additionally inside the bike triangle and simply a right side drive with a 2-stage chain reduction employing the BB axle as an idler shaft for a spinning connected dual sprocket.

Some early design considerations and contraints:


You do not need pedals on cranks connected to the rear wheel to subsidize this motor. You may prefer pedals to foot pegs.

Much like the electric cars, having one ratio of gearing can cover most your performance needs because of the power/torque of this motor. No derailleur needed. One gear ratio suffices.

Motor chain size and rear wheel chain size along with how you will manage the pedal/crank connection to the rear wheel determine how much and how heavy of real estate you will need between the right side of the bottom bracket and the left side of the right crank. The motor comes with a type 428 sprocket which can use #40 Chain as the cog width is 5/16". This cog could be milled/ground to 3/16" width and then a #415 chain would suffice with the 150 amp votol controller. #410 chain seems a little undersized for strength to me but should you want, try #219 go kart chain? Some are sold on it. Likely with bigger chains you have more weight but less chain adjustments, replacements, sprocket wear and a lower pitch chain running noise.

The other early needed detail is whether the cranks must be able to rotate 360 degrees and if so they then must have enough separation to clear the motor on the left and the motor's chain guard on the right.

I had a group of various ISIS axles and square taper axles at my disposal but based on the motor width (215.15 mm = 8.47" ) and pedal/crank rotation desired plus the double cog space needed this square taper looked best suited for the suspected length needed.

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Using this crank part #20432 from MBRebel.com I ended up with clearance of 1/4" on the left and about 1" on the right. You cannot shift this spacing because of the built-in bearing stop(s) on the BB axle. However there may be more lengths of the square taper axle than I found. You can get cranks from MBRebel that bow out quite a bit more than the standard crank offset and with these extra bowed cranks you may come up with the motor clearance needed while using a shorter axle. With this wide motor your steep q-factor is gone.

See axle at: https://mbrebel.com/?s=20432

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Note this square taper axle has a key-way slot and is a standard round diameter = 0.6250" = 5/8 " giving more common bearing options than an Isis axle does.

AFN
 
This dual sprocket BB hub (DSBBH) occupies about 1.4" on the BB axle when using #40 chain and #415 chain.
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There are 4 bearing units within this hub and the chain loadings are on the axle not the crank arm.

Knowing the DSBBH width and the motor length facilitates deciding motor frame dimensions. Here is the DSBBH on the chosen axle.IMG_0649.JPG We will proceed to the motor fame making and come back to making the DSBBH later.

Having had both the Cyclone 3K and Cyclone 6K I had various motor frame plates from old & new kits. To just copy the Cyclone motor frame would push the somewhat bigger QS 3000 motor closer to the ground which is not what one can have with an edirtbike. A longer motor frame is needed to get down tube clearance to raise the motor. The Cyclone motor frames length ends up with about 12" of motor clearance to ground whereas with just a little more frame length my QS motor has 14" of ground clearance. Simply more motor frame length would make for a more wobbly frame.

Most of the ebike motors of power 3K and above have shapes of cylinders and have mounting thread holes on the ends. The Cyclone 3K, Cyclone 6k, QS 3000 and QS 4000 ( possibly the QS 2000 also) have cylinder-like rims on the ends that have a diameter of about 130mm. It turns out that the right side Cyclone motor plate curve fits the QS motor ends also.

For this QS motor frame the Cyclone motor plate was converted to a triangle with a round top.
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Here we see the triangle motors plates fastened to the BB bracket. IMG_0651.JPG

I claim here identical, becasue, even though the motor plates were jig sawed from the same width flat steel plate, they were then clamped together with factory edges matching and the jig saw cuts were then ground to make for a straight/flat surface. The 1 3/8" holes in the triangle plates for the BB hardware were "sawed" on a drill press using a new 1 3/8" hole saw while the two plates were clamped together.
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Motor side Plates

The motor side plates bolt on the ends of the motor and they are curved to match the end cap's short cylindrical rise. The QS 3000 has 6 - 8mm x 1 threaded holes suited for a plate mount similar to the Cyclone motors. The motor comes with a single pintle hook mount plate
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fastened on the central shell of the motor with 4 bolts. Likely to match the down tube angle you will want to rotate this central anchor 180 degrees so that it's transverse bolt is at the top of the motor when mounted in frame. Just down the down tube from the bolt are slots that accept a gear clamp or large cable tie which like Cyclone such is used to keep the motor frame from rotating down.

A pattern for the motor side plates can be copied from the right side Cyclone Motor plate. Your motor likely will run cooler if you make the motor sides plates long enough to leave a space for circular ventilation , say 1/2", between the motor and the motor face plate which is the retangular steel plate that connects the 2 side motor plates.

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If jig saw cut out, clamp these motor plates together and grind them so they are the same size to 1mm. Drill 2 holes in these to fit 2 of the threaded holes with the motor side plate centered between the 2 bolt holes. My center line of the motor side plate is 120 degrees from the top. Fasten these plates to the motor.

My original plan for the motor frame was just 5 steel pieces -- 2 BB triangle plates, 2 motor plates and a common face plate. The 2 pairs of side plates would be welded to the face plate Collin Furze style -- adjusted on the spot and bang with the welds.

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The plate mentioned in the above photo was the first piece of plate welded with a 3/4" piece of wood giving it some rise from the down tube. The motor frame then became a 6 piece frame, instead of 5 pieces. This sixth piece of plate makes for a shear wall plate which both stabilizes the triangle plates for the rest of the welds, sets up alignment/reference points for measuring and stiffens the frame laterally for torque loading.

The motor plates were next welded to a centered rectangular plate that was 2 thicknesses 2 X 3/16" = 3/8" longer than the end to end distance of the motor plate separation. With 3/16" projecting beyond each end of the motor plate one can fillet weld it to the motor side plates rather than doing a mere lap weld.

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Trade Offs

The 5 piece frame is quick to make but has very little adjustment. By adding another face plate to triangle frames (now 7 pieces of plate steel) the motor fame system can be made adjustable for chain stretch by bolting the two face plates together. Also, if you did not get the motor axle colinear to the BB axle, a new adjustment would be possible by getting a rematch lineup and drilling new bolt holes. If down the road you get some other cylindrical motor to mount, you would only need the 2 motor side plates and a face plate.

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To facilitate motor alignment an adjustable webbing strap clamp was useful when ran around the motor and the interior shear wall plate that is welded between the two BB triangular plates.IMG_0700.PNG

These screw C clamps were used to hold the two face plates ( the motor face plate and the BB triangle face plate tightly together after proper alignment for drilling 2 securing holes. There are now 5 holes in the face plates threaded for 8 mm bolts on the motor face plate. I made my first loose chain adjustment using 2 pairs of plastic ez-shim shims running counter incline wise to each other. Pushing these shim wedges in this alignment insures parallel transport of the motor frame outwards with a mechanical advantage from shim wedges. The system moves easier when the the down tube clamp is loosened.


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Next I will cover how the double sprocket BB hub (DSBBH) was made.
 
The double sprocket bottom bracket hub (DSBBH) consists of 5 major pieces along with washers and shims. The QS 3000 motor position left to right is determined by where the right most of the sprockets is from the BB shell. You may have some leftover axel space on the right as depending from which companies freewheel you get these components as they are merely similar, not identical. The DSBBH used for Cyclone kit builds has only one bearing. Using their set up with bigger chains would push the rear wheel chain's sprocket loading somewhat beyond centered over the bearing in the BB freewheel hub. Here is a look at the chain size at the BB axle.

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I decided not to attempt the wide chain and load balancing act employing a Cyclone BB configuration which has only one bearing. I wanted pedals as opposed to foot pegs but did not need any form of pedal assistance. This choice meant the DSBBH could simply rotate on the right side of the BB axle. The ISIS axle is less suited as its diameter in the right free space is not as standard as square-taper axle which is 0.6250" accurately.

The DSBBH would have to have the sprockets connnected by bolts, thread shaft or welded. Flanges as opposed to actual chain rings would permit changing bolt-on sprocket sizes. There is sort of an ideal piece for the to rear wheel sprocket when using #415 chain and seeking a small cog.

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The other sprocket/flange choosen was the White Industries BB freehub also RHD.IMG_0500.JPG

After I figured out a way to add a bearing to each of these, additionally as they have ratchet bearings, I first considered welding them together, then considered bolting them together but after finding a strong enough coupler rod threaded 13/8" x 24 and having a 5/8" hole through it, I settled on using a threaded coupling.

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Note the left side in the photo above has a square tape bearing holder end cap screwed into the flange hub. A free spinning DSBBH could be made this way but it would end up wider than ideal and bolting the flange hubs together is not the best way for long lasting stable alignment of these hubs on a shaft.

There are several coupler like items for connecting these two hubs that have the correct threads and a bore large enough so that 5/8" shaft can pass through it.

So what we seek is a compact form of 2 sprocket/flange assemblies well aligned and bearings for each. The item looks like this:
IMG_0639.JPG
 
COUPLERS

There are at least three pieces of threaded stock (RHT 1.375 x 24TPI) on the bike market that could be used for a coupler of the two freewheel hubs used in making a DSBBH.

1. Included in the Cyclone BB kit for widths of 110mm & 120mm BB shells are some THIN threaded couplers for use in the kit for extension of the BB shell on the left side which is RHT. You would saw off the length you need as these are 1.375" long. SickBikeParts sells this piece in a kit for Cyclone mount wide axle.

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2. Staton Inc sells a long threaded (RHT 1.375 x 24 TPI)tube with a 5/8" hub & hole. Again the threaded section is much longer than you need. The coupler has a full annular section and could take a lot of torque.

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3. The earlier versions of the English BB assembly had ball bearings in a retainer that had RHT end nuts on the left suitable for the coupler we need. They are not all the same. Some are more compact and suited for use here.

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Kits for repair of this type of BB bearings have versions of this coupler included if you cannot find one of these couplers on the old bikes in the basement of the bike shop.

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I did some engineering calculations for torque and shear on the first 2 mentioned couplers and found the Cyclone coupler likely low and the old English coupler at 544 ft-lbs in pure shear. The Staton coupler is obviously strong enough for this motor and controller but lacks the convenience of being "just right" in length. Do note that in this assembly the coupler will tighten the two hubs together making for tension in the coupler but compressing the two sprocket hubs tight together on their faces. Some of the torque will then be transferred accross the bearing faces by these normal forces compressing the bearing faces together and generate an associated friction sheer. Making use of both tension/compression and shear in a material results in a stronger design.

A bearing assembly that fits (sung) inside the two sprockets looks like this or shorter in overall length if you get the lower profile coupler mentioned in the photo above. Space is a premium.

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These bearings are either slightly too big to fit the hub or a little bit small to carry the loads depending on which freewheel hub you employ. If you use a White Industry flange type freewheeel hub on the right you will need to mill out about some approx 0.010" diameter to get a press fit for the bearing insertion.

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Bearings and Coupler Installation

These 2 freewheel hubs have 4 possible ways of being joined with the coupler. Only one combination of these RHS (both have RHT) mount hubs will work for this application. These freewheel hub have some slots on only one side where the removal tool is inserted. The slotted sides are placed outward from their mating surfaces that come in contact when the coupler is being tightened.

Starting with the left side whose sprocket chain goes to the rear wheel sprocket we mill out the hole to fit a standard square taper bearing tightly.

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There are some "home lathe" ways to do this enlargement and mine done this way is still working. More on this later.

You will want this fit to be more of a press fit than a slip fit as this sprocket gets a lot of tangential pull plus the bearing outer surface area is bigger than than the area you mill out. But you can mill out a fit for the right side of this bearing into the coupler and then get support for the bearing on its right side.

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The bearing end fits into the coupler. Say 0.05"

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Next start threading the coupler into the left freewheel hub with the bearing pressed into the coupler until 1/2 the threads remain visible. But before screwing the Coupler into the freewheel flange coat both surfaces with an anti-seize lubricant.

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Next push the other ST bearing into the milled to fit tool removal side of the right side flange hub deeper than flush to the outside of the hub.

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Now thread the 2 hubs together and if upon getting tight the right side ST bearing does not move to flush with the outside you will need a washer spacer with hole > 5/8" and OD less than 1 3/8". You may have to mill, file or grind a thick washer down in thickness to get the correct fit.


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Here we see the DSBBH compete and reddy for the axle mount.

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Shim stock tightening the bearing ID to the axle next time.
 
Shiming the Bearing Axle

The square taper axle has 2 zones of case hardened chrome steel where the ST bearings ride and they fit tightly in these shinny zones. On the black sections of the axle the bearing is not very tight. In fact the inner part can be turned when on the black part of the axle. This bearing inside turning when the axle is acting as an idler will likely cause fast wear on the axle and less on the bearing because it is quite hard steel.

Depending on how much smaller the shaft diameter is to the bearing ID, there are a couple of methods for stopping possible rotation. Let's say you have a snug fit, but using a plier to grasp the ID bearing edge you can easily rotate the bearing ID piece on the shaft. Maybe with clearance at say <0.001" the Loctite 641 may be sufficient.

From Google:
LOCTITE 641 is designed for the bonding of cylindrical fitting parts, particularly where disassembly is required for servicing operations. The product cures when confined in the absence of air between close-fitting metal surfaces and prevents loosening and leakage due to shock and vibration.

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Or maybe the strongest for more $$

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Or a green ND industries shaft lock form Staton

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Before applying any shaft lock to each mating surface clean them with some solvent like white gasoline to get rid of grease. If you have silicone contamination, you may need to sand it off the surface.



Measuring the black part of the ST axle yields consistently 0.6250" diameter. The chrome part of the shaft measures 0.6304" diameter and the bearing is about 0.6305" diameter. To get a tight fit, we need a shim stock thickness to make up the differences of the two radiuses.Calculating (06305 - 0.6250)/2 = 0.0028" thickness. Since most shim stock is available in each 0.001" we would use 0.003" thick shim stock.

Cut from the shim stock a piece of brass in length equal to or greater than the DSBBH length. For the width you can wrap this piece around the axle, then mark and cut square with a siccissor or exacto knife so the edges just butt each other. Wrap this up and push the shim stock into the DSBBH. If the hub presses on the shaft easily you probably would be better off additionally using one of the shaft lock sealers. My bearing fit required some hammer taping and would not pull off using hand power alone. I did not apply any shaft lock to either of the 2 shim stock surfaces.

Be careful from whom you buy shim stock from as prices vary a great deal. I used some K&S hobby shim from Ace Hardware at some $5 per sheet.

Over the web:

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For a wide selection of shim stock and material type at very reasonable cost

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Before your final lockdown or press down of the DSBBH on the shaft you will need to add a thrust washer on the left and some spacers on the right to keep the hub from moving left or right on the axle. Or Maybe not with shaft lock? 4 sq in x 1700 lb/inxin = 6800lb to pry the hub off. I thought a brass thrust washer on the left is the wiser configuration and added one, having used no shaft lock.

Shaft lock could have been used earlier to fasten the outside rims of the bearings onto freewheel flanges.

Next time: washers & adding Pedal assist plus a bronze bushing for DSBBH instead of the the bearings.
 
Thrust Washers

Thrust washers keep members from translating and certainly the strongest shown shaft lock could stop translation on this application. A shaft lock of 3800psi in this application could withstand a torque of (4 x 3800 x 0.625/2)/12 = 395.8 ft-lb. But washers employed are much cheaper, easily removed and adjustable/easily removable down the road than a super duty shaft lock.

The DSBBH occupies about 1.4" of the 2" of free space on the right side of the BB axle. You will need about 0.6" of washers to stop translation of the DSBBH. But you do not want to put sideward pressure on the bearing hubs ID's from an over tightening of the right crank arm which then will push on the washer stack. So measure with a feeler guage the washer stack slack while approaching tightness during tightening the right crank arm. A slack of 0.002" will suffice. You may have to mill a washer in thickness or use shim stock to get this result.

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Generic Freewheel Flanges

A white Industry front freewheel flange is $85 and the generic models are <$20. They are no more difficult to employ than the White Industry version. The hole size in the generic models is bigger than the standard ST Bearing OD. But in the Hillman Fasteners section of the local Ace Hardware is the proper size bearing needed after milling out the threads. The bearing is OD = 1.375", ID = 0.625" and thickness is maybe 0.4" thick having a cost $16.00. Doing this installation will result in a thickness just larger than 1.4" as the generic hubs are wider than WIH's.

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The other way of installing a bearing into these generic hub is to use the bearing retaining Sqaure taper BB end cap (left side --RHT). If you grind off the unthreaded part of its rim you get a tight bearing fit into the generic hub. You likely will need either thread lock or a tight lock ring to keep this part of the assemble from loosening.

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Adding a Front Freewheel to Achieve Pedal Assist Capabilities

This task is somewhat easy but Why? Maybe a law officer needs a demo of motor-bike status? For an edirtbike this very low gear can give stating assistance when starting from a dead stop on a quite steep hill. With a ratio of 48/16 to the rear wheel this is about equivalent to riding a tricycle with a 9" wheel -- very slow.

Unless you used big diameter thrust washers this generic front freewheel will fit over the thrust washer stack but not reach the big sprocket going to the motor. To install, remove the crank and thread on a generic front freewheel.

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Tighten the crank arm to the ST shaper shaft and then add 5 long 5mm bolts to the threaded holes of the hub. Next align & tighten it such that the unthreaded holes are about centered between the bolts that hold the big sprocket to the White Ind hub. Measure for the spaces/standoffs needed -- grind 'em to fit. Then drill hoes for taping 5mm threads into the sprocket. I converted a regular 5mm tap to a bottom hole tap by grinding off about 1/4" of the tap tip. You are not likely to put a hole in the White Ind Hub by drilling as it is very hard steel. Tighten the Allen bolts and you are good to go pedaling -- after removing the 5 bolts used for temporary rotation restraint.

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After installing the pedal capabilities that some 2 inches of axle space on the right is mostly used.

Next: building the rear sprocket adapter & chain slack management.
 
Adapting Generic Sprockets to Shimano Type Rear Freewheel Hub

There are 3 or more ways to attach a non bike un-splined sprocket to the Shimano like rear freewheel Hub.

1. Take the sprocket and freewheel hub to machine shop with laser cuting options. The hub is used to make the pattern the cutter will use.

2. Buy some sprocket adapters out there from market. I have used 2 of these. They both had the Shimano spline pattern except the single large tooth on the adapter has been reduced to normal size tooth so the adapter fits either side outward.

The spider type may be the easiest to employ. Projection Racing of GB makes one (choose SS vs alum)that fits the 104mm bolt pattern and has the Shimano splines pattern. Simply bolt the outer 4 chainring bolts through it and the sprocket. If your sprocket does not have the 104 bolt distance hole pattern you will have to drill the holes which need centering about the hub. Some rear (large) sprockets from Cyclone, SickBikeParts and Staton Inc come with a 2.11" center hole which is the same diameter as a 13T cassette sprocket. Inserting this size sprocket into the 2.11" hole and then inserting this combo on the freewheel hub and lastly adding the Projection Racing Spider will set up drilling the holes accurate enough for bike wheels likely high RPM's? Max 800 rpm = 60mph.
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For the Cyclone 6k motor I used a Projetion spider on each side of the sprocket. For the QS3000 motor I used 2 spiders on each side of the sprocket. IMG_0850.jpg

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Use spacers on each side to align rear sprocket with BB sprocket. On the far inside start with a #41 sprocket ( bike size chain)about 1/2" in radius smaller than the drive sprocket and separated from it by more distance than the chain width. This space can catch a derailed chain to the inside and save your spokes from a chain grinding.

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Another hardware item for adapting is the Problem Solvers adapter which has Shimano hub splines and the 6 hole bolt pattern used to attach the disc of the disc 6 hole brake pattern. Conveniently you can use a larger brake disc to go from the 6 hole adapter to the outer rim of the choosen sprocket to bolt down-connect. To get a slip-on fit with the disc to Shimano freehub you will need to grind off a little bit of the 6 holes' loops on the inside of the disc.

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Now drill some 6 holes to fasten the brake discs (one on each side)to the sprocket.

Luna Cycle sells a 6 hole disc brake size spacer( when in stock) that can act as a spider and fits the inner 5 hole bolt pattern on Cyclone sprockets.
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3. Get sprockets and spiders from old cassettes which are often free from bike repair shop's junk box.
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The finished home made sprocket attachment can be quite substantial.

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Drilling the holes in chrome steel cassette sprockets may be difficult. Center punch deep and heavy, then drill with a cobalt bit on a drill press. Carbide tip twist masonry drills are not sharpened to the best angle for cutting steel but when new they can cut/grind into very hard steels.
 
Skip the bicycle freehub if you intend to push any real power. Just get the extremely robust and inexpensive Oset hub which has a 6 bolt pattern on each side, they sell a spider to mount kart sprockets directly from there.
 
Maintenance and a New Design of a DSBBH Employed

After about a month of trail riding some noises were coming from the DSBBH area. Off came the pedal assist freewheel hub still functioning, but not to be replaced. When failing to summit on a steep hill, the bike invariably goes a little downhill and you then get positive reverse pedal rotation at a moderate rate of rotation. The rotating pedals can hit you in the shins and make a certain zone below the BB off limits for standing and recovery.

The DSBBH was still on the ST taper shaft tight and was removed from the BB axle using a pickle fork. The shim stock held both bearings tight enough to stop any bearing ID rotation. With the DSBBH in hand the origin of the noise was obviously from the almost hung up ACS FAT 16T freewheel. This hub has a 3/16" width which is the tightest fitting width for #415 chain but the inexpensive fixture has no seals. Curious about the extent of its intermittent lockups I decided to take apart the DSBBH which likely was tightened considerable with the QS 3000 tugging on its flanges.IMG_0562.JPG

The DSBBH assembly came apart with out any trouble (remember the anti seize?) and White Industry flange was smooth as ever. BTW both ST bearings I added to the hub were still very tigh and rolled smoothly. This design is sufficient except if you ride water and mud you will want a sealed bearing version of the motor chain flange. I could not get the ACS freewheel sprocket apart for further inspections.

Bushing Version of a DSBBH

Having recently read that bushings can continuously handle 800 rpm of rotation speed, I was inclined to make a version of the DSBBH employing bushings and no roller bearings. Say you had a 1:1 sprocket ratio on the rear set of chains, 800 rpm at the wheel would give a ground speed of about 64 mph for 26" rim with mid fat tires. I very very seldom go this fast on a bike. So yes bushings have a feasibility for me.

Bushings are made in lot of standard dimensions often needing no reaming(using a Critchley reamer).Standard sizes fit well when pushed together and no special tools are needed. The central coupler would have to rotate on the 5/8" ST BB shaft so a coupler of 3/4" ID would use the standard 3/4" x 5/8" bushing. The coupler would hold the 2 sprocket flanges. Staton Inc makes a coupler adaptable to this situation......

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This coupler is sort of longer than néeded as far as actual thread length so the threaded end is ground to a taper to fit farther into the tool removal insertion end of the White Ind freewheel sprocket.

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Next 2 -3/4" x 5/8" flange bushings and part of a straight 3/4"x 5/8" bushing were drilled with a 1/16" hole to allow for grease to travel from the keyway slot to the interface of the bushing with the 5/8" BB shaft.

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With the flange bushing pushed into the coupler we get an overall dimension of 1.9"

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Next a Cyclone generic flange freewheel hub was threaded onto the coupler. The tool removal insertion side of most generic hubs has a diameter bigger than 1.375" and needs no milling to fit over the coupler. The ACS hub was replaced with an 18T WI freewheel sprocket. Despite the teeth width of the WI freewheel is only 3/32" as opposed to the 3/16" width of the ACS freewheel sprocket the #415 chain rides fine.

The generic flange freewheel has no seals against dirt and water so this is also a test of how an unsealed right side hub fairs in dirty conditions. I have since after mounting thought of some ways to seal it. A thin washer-Spacer was added to allow room for the thickness of the metric grease zerk. To get a grease gun fitting to attach to the zerk more space was needed between the zerk and the big sprocket freewheel than a straight one allowed, so in the working version of the usable zerk you see an angled zerk.

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The final assembly width at 1.9" plus some thrust washers on each end exceeded the free space on the BB axle by about 0.1" so some aluminum with threads was ground off the crank. This zone has a round inside and it is not part of the square taper fit space.
 
Hubs

The QS3000 motor at 13,800 watts overpowers some aspect(s) of most standard bike hubs. With Shimano rear hubs the free hub fails first.. After you weld it the engaging spur twists off the hub and you need a wheel rebuild, but with what hub? Likely with this motor you will make a one-speed.

Earlier Grantmac recommmends OSET hubs

https://shop.osetbikes.com/hubs/

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As for the 6 bolt mount the OSET hub has for a drive sprocket, the pattern seems a little insufficient as I have sheared this same 6 bolt pattern running my Cyclone 4K at about 7Kw.

I am currently working with this steel hub as a spare wheel in case my DT Swiss 350 hub fails.

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A variant kit of this HD hub from gas engine suppliers:

https://www.bicycle-engines.com/solid-sprocket-hd-axle-kit-w-brake

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https://www.grubee.net/collections/traps-bullet-and-box-1/products/hd-axle-model-1-with-freewheel-hub

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But there are other folks working on building stronger hubs. Gemini Bicycle Products may soon have an aluminum heavy duty hub

See: https://m.youtube.com/watch?v=X-DCXN-aYEg

Another heavy duty looking hub is the Jitsie which is made of T7075 alum (shear strength 48,000 psi))which is somewhat stronger than generic T6061(shear strength 24,000 psi).

https://trialssuperstore.com/products/jitsie-rear-wheel-race-hub-135mm

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An real heavy duty rear hub from Jitsie is in the Moto category. It may need some shaft/dropout additions to fit a normal 135mm dropout.

https://www.jitsie.com/en/wheel-hubs/47956-hub-rear-wheel-race.html


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White Industries makes a similar hub to the Jitsie Race Hub but out of T6061-T6 (shear strength 38,000psi)

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If you build a HD hub that has 1 3/8" x 24 RHT there APPEARS to be a useable HD Steel adapter from Grubee with the 6 hole disc brake pattern but it will not fully thread onto the English thread. The reason it does thread for some distance is that a metric thread pitch of 1.0 mm is 25.4 threads per inch which is close to 24TPI. Plus a diameter of 1.375" = 34.9256 mm which is also quite close to the 35mm diameter.


https://www.grubee.net/collections/skyhawk-2-cycle-all/products/hd-axle-hub-for-disc-brake-attachment
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Gearing Ratio Changed

I got a chance to try a lower gear ratio for hill climbing with the QS3000.

Ratio is 42/14 x 48/19 = 7.58. This makes for less front wheel air time. The bike and me at 155lb cannot quite do a standing dead stop burnout(front wheel against a wall) but with the slightest unweighting the rear wheel gets loose and spins. The ratio seems like about the right choice for hill climbing and my weight.
 
A couple of worthy add-ons for an edirt bike using QS controller 150 Votol.

The controller has some fine (small wires) that could get ripped off so a cover was added to cover that zone.

Alum angle cover protects small wire ports of controller
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Some of the sidehill rides I do have a lot of brush -- Mountain Mahogany -- which scraps your finger etc. Now guards have been installed.

Cycra guard are quite bomb proofIMG_0940.jpg

I have some much cheaper eBay generic brush guards on the other ebikes and they work adequately.
 
Tire Tread, Rubber Stiffness and Mounting Direction

Bigger bike motors and low gears chew/wear off rear tire tread much quicker than the front tire wears or a pedal only bike does. Some mt Bike tires have hard rubber (KENDA) but the trend seems to be going to soft/sticky tires (MAXXUS). Most of the MTB tires have an asymetrical tread pattern and on the tire side is an arrow for the direction of suggested rotation. But a rear tire has to be good in ground resistance in both directions -- transferring push forces and braking.

So what is best the best tire setup for an edirtbike? If we look at gas motorized dirt bikes for tire styles, we see a full thick block/cliffed pattern of tread and a rubber that is at least as hard as the Kenda NEVEGAL PRO bike tire. But almost all MTB tires do not have a full block-cliff pattern for tread but instead the blocks have 3 sides with cliffs and one side with a ramp. Cliffs are about gripping in dirt and ramps are for a quieter tire ride. Braking in dirt is achieved better with cliffs employed as the first line of contact in tire rotation. IMG_0946.jpg

The front tire type model & mounting are somewhat obvious -- you want stickyness and braking. Best braking occurs when cliffs faces of the blocks, not ramps, resist the motion. This usually is
the direction that is suggested on the tire side.IMG_0949.jpg

The rear tire choice often requires studying tread pattern for best gripping in push traction not braking. The cliff face of the block meeting first will give the most traction over the ramp side first. Let us look at the Kenda Nevegal PRO used as a rear tire.IMG_0948.jpg
Note this side tread piculiarity. We are comparing two MAXXUS tire treads both tires of which are downhill on the HIGHROLLER (front or rear?)and the MINION DHR. The Maxxus HIGHROLLER by feel seems to have a harder rubber than the Minion DHR.
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Why not choose sticky rubber for both the front and rear tires? The sticky rubber tires cost more and wear out quicker than the hard rubber ones plus these MTB tires have a much shorter life than real motorcycle tires, which are hard rubber for the most part.

The other consideration involves which measure of friction comes into play for intended use. There are two measures for the the experimental coefficient of friction -- the static measure and the dynamic measure. The rear tire often spins while coated with water, wet mud or simply dust. Think dynamic and likely where sticky outperforms is very slow and dry not wettish with slippage.

So to sum it up: soft on front, hard on rear. Tread rotation for best braking on front and tread rotation for rear is to get the best push traction which if often opposite of the suggested rotation arrow.

The Surly Dirt Wizard has no specified direction of rotation. Obviously the tire is not downhill rated with only 60tpi as opposed to 120tpi but the rubber seems harder than a typical Maxxus MTN tire. Here pictured is the Surly Dirt Wizzard front mounted with lugs oriented for braking not traction. IMG_0658.JPG

Durometers is the measure used for rubber hardness which in the opposite direction may not be stickyness but softness. For stickyness I simply test for the sticky feel. Maybe there is an actual measurement for stickyness?IMG_0952.jpg

When is a tire worn out based on lug height? It seems when the lugs get shorter than 1/8" of height I get too much slippage. Car tire wear bars are raised 2/32" . At 1/16" lug thickness dirtbike tires no longer grip enough for dirt hill climbs but may work fine on pavements. Compare this worn out tread ( for my use) Halo Contra show below to a new Halo Contra shown as first pic in this pwost.IMG_0953.jpg

Traction goes up a little on these worn out tires when using a little lower air pressure but .....rim denting.
 
Rim Locks or High Tire Pressure

The QS 3000 motor has enough power/torque to rip a schreader valve stem from the tube. There are some two ways to prevent this rim spinning action in relation to the tire rotation.

1). the easiest way to stop this slippage is inflate the tire to it's maximum rated pressure. You get a rougher ride and less traction.

2). Install a rim lock. This item is a saddle like wedge that is inserted into the tube space with a bolt & nut protruding thru the rim from a hole that is drilled for this stud. The tire slippage is locked when the nut is tightened. They are somewhat common on moto dirtbikes but no such piece of hardware is made for an edirtbike as the tires/rims are somewhat smaller than moto tires.

The local Yamaha shop had the smallest Bike Master rim lock sized at nominal 1.6". On the rubber saddle was stamped "1.4 -1.6". A Sun Ringle MTX39 rim measures 1.13" inside which is too small for a good seated fit.IMG_0695.JPG

I was able to clamp the rubber parts of the saddle zone out of the way and grind this oversized wedge to almost seat flat to the MTX39 rim inside flat. I drilled the attachment hole as close as possible to a spot opposite the valve stem hole -- 180 degreees away. I also added some mid to high density foam to get a tighter saddle fit which keeps the tube from going into the rim lock space.IMG_1007.jpg

DRC makes a rim lock they call a 1.4" rim fit. See Chaperal moto sport for them. I have ordered this size hoping for a closer fit than the 1.6' yielded. IMG_0697.JPG

A switch to a foam core tubeless addition will allow quite low air pressure which would soften the ride and increase traction but does nothing for tire to rim slippage. A local KTM rider uses both the foam core addition and a rim lock on the rear. He says he is running 3 psi.. I have some foam cores coming but no experience with them.
 
Splitting a LiPo Pack

If you want to near maximize battery pack/controller voltage using LiPo's you may have to split a Turngy 6S pack. Your modified battery pack will end up with 3 x 6S + 1 x 3S = 21S which gives a full charge voltage of 88.2 volts. The 120 amp controller will just allow this much voltage.

Cut the blue shrink wrap with a curved scissors preferably on the side as the sides have a very durable under layerIMG_0716.JPG

The cells are glued together with a soft caulk that can easily be separated. I use the blunt plastic construction shims to separate the pack at the 3 - 4 cell junction.IMG_1069.jpg

The next feature to sever is the anode/cathode tab between cell 3 and cell 4. A tin snip scissors will be some what exacting with the cut. Carefully cut this joint so as to have mirror image symmetry with the electrical tabs on cell 3 and cell 4.

Cut one-at-a-time the balance wires at the JSTM plug. Desolder the red (positive) solder joint at cell 6. This lead is soldered to the positive tab of cell 3. You may find you cannot tin the tab as the solder will not stick to the aluminum of the tab -- aluminum oxidation hinders. Apply a small drop of says 3-in-1 oil to the tab, then heat the oiled spot with solder rod next to the solder gun tip and tab. After getting the tinning the pos terminal wire can be soldered to the tab. On this same tab add a balance wire.


See https://forums.qrz.com/index.php?threads/aluminum-how-to-solder-together-aluminum-wire-to-copper-wire.348081/


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Add the black rubber separators where the terminals may touch. Wrap the packs sides with the heavy white plastic that is used to wrap the sides of packs. You may have to get more of this white plastic from a dead pack. The 2" wide packing scotch tape will work to fasten the ends. Heavy nomax paper will also act as mild to good insulating barrier.

You can get wide shrink wrap on eBay for covering the packs, but a durable substitute would be tubeless rim tape.IMG_1080.jpg

Proceed the 2-pack conversion with the other part 3S of the 6S pack. You will need an XT-90 terminal form a dead pack or make one from parts sold at HobbyKing.
 
My QS3000 motor's sprocket drive came with a 20mm/17mm splined 14T cog and of a width for #428 chain. I could not locate a cog of #415H chain width and just went with a #40 chain primary on the initial build. The secondary chain was #415H and it has held up fine while getting about twice the tension as the #40 chain did. The late Fall improvement for this edirtbike was to switch the primary to #415H chain, get T7075 aluminum sprockets for the big rings, improve the DSBBH(double sprocket bottom bracket hub), clean up the idler/delrin chain guide and lastly make a non-freewheeling thread on sprocket adapter for the rear chain ring.

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To get a #415 cog for this motor shaft a #428 cog was essentially milled thinner on this homemade lathe/mill.

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Here the lathe/mill setup used for thinning the cog:

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The DSBBH was fitted with modified ISIS BB bearings bored to fit the Square Drive BB axle eliminating the need for brass shim stock to make the assembly snug. More to come on making these DFBBH(the F is for flange) in my QS2000 post.

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The Specialized suspension chain path depends somewhat on a derailleur to keep the chain from rubbing the lower stay. The Big Hit downhill bike came with a plate fitted for an adjustable deflection pulley but it was not entirely suited to my modifications for clearance and strength. A stronger than mild steel bed rail steel angle was fitted to the underside of the BB shell to hold the deflection pulley near the small secondary cog.

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The rear thread-on hub of the rear big chain ring was converted to a welded tight no-ratcheting hub. The welding was done to fix --eliminate-- freewheeling action. This motor destroys freewheel pawls and then you walk. More on these difficult welds next post.
 
The QS 3000 has destroyed a few front freewheel flanges mounted on the rear axle. In my previous post I mention welding them which makes for chain noise all the time while coasting. I do like quiet coasting. But some rides I do involve nearly 3000 ft of descent and return. If any freewheel hubs fail on these slopes, pushing the ebike uphill (heavy @ 90 lbs) to the vehicle is too difficult. A simple remove and replace of the flange freewheel hub is not likely in the field as they are on so tight that I would need to carry a 36" pipe wrench plus the removal tool to remove the failed hub. I do have a spare tire mounted rear wheel in the vehicle for freewheel failures and have gone for it on ocassion.

But is there a possible recovery method one could do on the spot just after freewheel failure?

My thoughts for this solution had been, " Is there a way to modify a freewheel hub such that maybe something like having a threaded Allen hole to screw a bolt into the hub would lock against slippage of the failed hub?" Likely it could be done but there is an alternative external solution. No modification to the hub is needed but you must carrry the 6 oz. recovery tool when you have a need for it -- anytime.

The simple recovery tool I made works best on the 10 hole ACS hubs. A tool for White Industry hubs is similar but harder to fabricate since there are not 5 free holes on these hubs. The ACS tool is made by welding 2 parts together. A big washer with 5 small bolt holes (pattern F5 about 2.65" BCD) is welded to an ACS freewheel removal tool. The top of the removal tool ( hex nut ) is ground off to make for enough space for the tool to fit within the space between right rear dropouts and axle hub while fitting into the slots of the failed hub -- narrow.

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A Jistsie rear hub and others with wide flange separation may not have enough lateral space for the tool to fit without it touching the dropouts but some washers on the axle my widen this space enough for the tool to not rub on the dropouts.

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The 14,000 watts of this low wattage controller/motor setup does a destruction job on the rear 350 DT Swiss freewheel cassette hub -- they can be welded -- then you have noisy coasts.

the major failing of this tool is that upon installation you have noisy coasts ----------
 
Billet Hubs

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The first hub was made from the alum billet.

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The alum hub with sprockets mounted was put on the bike with the QS2000 motor for tests of quietness.

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Acetal plastic is near the equivalent of DuPont Delrin plastic but somewhat cheaper.

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UHMW(PE) stands for ultra high molecular weight polyethylene and is quite cheap compared to acetal. The acetal costs a bit more than the aluminum. The UHMW plastic was chosen after reading about several plastics suitable for strength and machine ability.

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Despite several plastic melts a UHMW plastic hub was turned.

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Hubs made of the low melting point UHMW plastic, although very cheap, would likely melt some when a bearings rotation tightened up due to contamination or wear. The use of UHMW plastic for hubs seems not fully suitable.

Why so much on hubs? Dual sprocket hubs are the major source of ebike noise. The hubs made employing front freewheel flanges will fail soon to eventually under QS3000 motor loadings. The ultra strong flange hub posted and made of 4130 cromoly steel is hard to fabricate compared to billet turned hubs. The alum billet hub has been tested and works fine. Comparabe in noise production to the 4130 hub the alum billet hub would also likely be a little quieter if some polyurethane sealant were applied. I have not tested the acetal hub yet -- looks promising.
 
A White Industries Recovery Tool

For the rear hub of the QS3000 I use a sprocket welded to a thread-on adapter 1.375 x 24 tpi or the Ultimte White Industries flange freewheel sold exclusively by SickBikeParts.com. Either set-up on this edirtbike has always brought me home. As I prefer silence when coasting rather than the sound of moving chain, a freewheel flange is used on the rear hub.

Some have suggested the DT Swiss 350 rear hub will not fail. Not so for use on the QS3000.

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The failure was the rear sprocket's inner "teeth" wearing groves in the aluminum cassette carrier's knurling. The sprocket would rotate freely on the carrier. You can buy a steel carrier for the DT 350 rear hub at $90. I now have one. It is rather unscratchable compared to the aluminum carrier -- a test for which one you have.

That aside the 350 hub/ratchet performs noticeably different than a WI flange freewheel when mouted.

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An 18T one way clutch allows for 20 degrees of windup before torque impact on a DT Swiss 350 hub, whereas a White Industry flange freewheel has a 36T ratchet which allows for up to 10 degrees of windup before torque impact. When throttling after coasting the DT Swiss 350 hub is very noisy upon torque impact and the contact impact sends vibes through the bike -- disconcerting.

Superficially one could argue that the 18T of the DT hub, which mesh simultaneously, obviously yield a stronger setup than the mere 3 teeth of a WI hub. The ( 7075 alum ?)DT ratchet teeth are very small and act on very short radius. A simple geometric/material analysis of these two ratchet mechanisms predicts the WI freewheel ratcheting mechanism is about 2x stronger.

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Not all rear hubs have enough free space to mount the recovery tool even if you force spread the dropouts -- widening them a 1/4" takes some force. The Grubee gas engine steel hub and the WI ENOS hub can accommodate both the wide WI Ultimate freewheel flange and the recovery tool.

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Some of the nuts and washers of Grubee Steel Hub can be shifted so as to make clearance for the recovery tool.

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Mounting the 10 hole ACS freewheel Recovery Tool described earlier in this QS3000 post makes use of the extra 5 threaded holes in the flange. Since the WI Freewheels are made of some super steel alloy, drilling and threading 5 holes takes special carbide tools -- $$$. The use of shortened class 10.9 extension nuts serves both as the fastening method for the sprocket bolts and the left over threads on these long nuts permit fastening of the recovery tool.

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