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27

Early cassettes (Suntour Accushift and Shimano Uniglide being some commonly encountered examples) weren't like this. The splines were all the same and there was no hunting for the little spline or big gap. To summarize a bunch of history, these cassettes were current at the same time as early indexed shifting. Accushift and early Shimano SIS both ...


17

This sounds like a issue in your freehub/freewheel (both are mechanically the same for this question). This is what allows you to coast without pedaling. Inside these bodies are a set of "pawls" which will flip down and engage a series of splines when rotated "forward", and propels the bike forward. Then, if you move them in the other direction "backwards"...


15

Standard Pawl and Ratchet Design This design is by far the most common on bicycle freehubs, and as such the least expensive to employ. Mechanism In it's simplest form, this design consists of a surface that is toothed and a pawl (which is a lever that engages the toothed surface and only allows movement in one direction). In a bicycle this design is ...


10

American Classic Cam Plate Design The full name is "Six Pawl Cam Actuated Engagement System." This design is one of the more complicated ones, but according to American Classic provides a stronger freehub with relatively low resistance and causes all 6 double tooth pawls to engage simultaneously with high precision. Mechanism There are several parts to ...


8

I don't have specific experience with this one, but the pictures suggest it works one of two ways: From where you're at now, you bonk the end of the axle on the non-drive sufficiently hard and the axle slides out, possibly taking the freehub with it, or if not then letting it be removed. You put the 5mm allen in the drive side end and a cone wrench on the ...


8

Yes, there is. Shimano/SRAM & compatible seven speed is 5mm cog-to-cog, and eight is 4.8mm. Generally what you're trying to do here can't be made to work very well. There are some tricks that without any additional parts can increase the movement of the derailer, but not decrease it. Also if you have a true 7-speed-only chain (not common anymore but they ...


7

Most likely duplicate but I cannot find it. In the free hub / free wheel you have pawls that are the coast / drive mechanism. Most likely they are gooked up or just plain broken. Some are serviceable and some are not. FREEHUB SERVICE You can also search on youtube. Or just take the wheel to a bike shop. You might be able to free it up with a bit of ...


7

Star Ratchet and variations This design in it's simplest form is used by DT Swiss. This design incorporates easily replaceable ratchet plates that offer the added benefit of every engagement point transferring torque. A more complicated variation is what is used in Chris King hubs. Mechanism - DT Swiss 1. end piece 2. bearing 3. thread ring 4. axle 5. ...


7

If everything is shifting smoothly and the hanger is aligned, it's very likely the freehub body slipping intermittently, which feels much like the chain slipping. Usually it takes a visual to be sure it's the freehub and not the chain. Different freehub designs call for different procedures to fix and investigate this. The root cause could either be overly ...


7

I believe this one is a 12mm allen inserted through the non-drive side. 11mm is out there too. Usually what I do is clamp an L-type one in a vise, long end up. A long socket would also work but it would need to be very long.


7

Simple answer: yes, but it’s not worth doing. Cost of hub, spokes, nipples and having wheel rebuilt will exceed the cost of a new wheel. Even if you re-use the spokes a new wheel will still be cheaper. Wheel building requires special equipment, expertise and time to do correctly.


7

Yes - I have personally done this, by installing an 8 speed cassette freehub into a wheel that had a 6 speed freewheel. The donor was a 26" MTB wheel, and the recipient was a 20" wheel for my folding bike It was only worth doing because I had a donor wheel and I was able to reuse the 20" spokes well enough. I even reused the 8 speed cassette and chain. ...


7

Do any other manufacturers use internal ratchets in their freehubs? Many other companies manufacture freehubs with internal ratchets, both clones that are Shimano compatible and variations of their own. Specific branded examples include the Giant FH06 freehub or the Bontrager Select freehub, but like most hubs and freehubs these are likely OEM and sourced ...


6

That's a freehub body. Look on the hub for the model of hub you have, and then you can use that to find the appropriate freehub body model by looking at the documentation of the hub.


6

There are no thru axle FH-6800 or WH-6800 versions. The next/new Ultegra will have some, but as of now I don't think think any thru axle hubs or wheels that say Ultegra on them are really out in the wild at all. This bikes uses the SCS dropout/hub/axle system. Long story short, in the past couple years it was unclear what road thru axle standard was going ...


6

It looks like a Helicomatic. Once you know the name, there is plenty of information on the Internet.


6

For maintenance and reliability, you can probably rank them in approximate order of the White freewheels being best at everything, then the premium singlespeed cassette hubs (King, Profile), then after that I'd put the nicer BMX freewheels, then the nicer generic-brand singlespeed cassette hubs (Novatec), then the junkier singlespeed cassette hubs, then the ...


6

As the others have already stated: Yes, it is possible, but ... However, I feel that the really important message has not been transported yet: Building a wheel is not easy for the uninitiated. Yes, it can be done. Yes, you will likely get something that looks like a true wheel. But you may easily end up with many broken spokes the weeks after. The ...


5

Sprag Clutch The sprag clutch has existed in industrial applications for some time: being used in motorcycles, helicopters, airplanes, automotive transmissions, and others. As far as I know, Onyx is the only company to bring it to bicycle hubs. Sprag clutches offer low rolling resistance and virtually instantaneous engagement. They are also reliable and ...


5

I am going to combine the comments into an answer - feel free to improve. The main benefit is the larger circumference of the ratchet surface. This means for the same torque on the wheel, there is less total force on the ratchets holding the freewheel. It also means there is room for more pawls, meaning less force on each individual ratchet. This allows ...


4

Here is the explanation to what happened: The freehub bearing had been moved outside for about 2,5mm. When reassembling the hub, the body wasn't sliding as far in the axle as it needed to. Thus, the pawls were not centered in the notches and not engaging. But, I did replace the freehub body and pawls first, and they were engaging. However, when placing a ...


4

When you cleaned the rear hub, did you reassemble it in the right order? Sounds like your axle is too far over, or there's possible a lock nut in the wrong place, so that when you cinch down the QR, the dropouts are touching the axle (OK) and the wheel hub (not OK) If the wheel spins okay on its axle/bearings when off the bike, then something about ...


4

I believe on this one you put a 5mm wrench in both endcaps and turn counterclockwise. You're trying to get the drive-side endcap off. If it's the non-drive one that breaks free first, there should be a larger size allen fitting in the end of the axle that will be exposed when you take it off. Stick the 6mm or 8mm or whatever it is in that and then you can ...


4

I just did this hub yesterday. Used 17mm cone wrench and I think 5mm allen on drive side at same time. Cone wrench held in place and allen (attached to axle) turns CW as if tightening. Loosens up and then you spin the nut right off. I was only servicing the free hub so did not work to free axle from hub which likely takes a hit with mallet.


4

The freehub was the issue. As it turns out, the bicycle manufacturer (Pinnacle) have issued a recall on the rear wheels of a small number of units of both my bike model (Arkose 4, 2016) as well as another model sharing the same rear wheel (Arkose 4, 2017). It seems there were manufacturing defects in a batch of rear hubs/freehubs, causing the pawls to fail ...


4

The part with the two notches is left-threaded, so clockwise to loosen from the perspective of your picture. It should be noted that these are quite the can of worms once apart, and cleaning/lubrication can be done pretty effectively by taking the whole freehub body off using the 10mm internal Allen wrench flats (poke a 10mm Allen into the hole in the ...


4

Of course it is possible, you're simply building a new wheel with some used and some new parts. Unless we are talking about carbon rims where the spokes are glued and the wheel is trued in the factory already. When doing that take the following into consideration: is the new hub as high as the old one (you have high flange hubs) - if not, new spokes will ...


4

To remove the freehub the axle has to come out. Before you start source two new bearings as it is likely they will need to be replaced after you remove the axle. You can try to "gently" tap on the axle with a soft faced hammer (hard plastic or brass). In a pinch you can also place a block of wood on the axle and hit the wood with a steel faced hammer. One ...


3

Since the cassette is being driven by the wheel, the freehub mechanism is catching instead of releasing. Confirm that by removing the rear wheel, remove the cassette, and spin the wheel/freehub off the bike (ie in your hands) When powering it through the freehub the wheel should turn like normal, but as soon as the freehub is not driving the wheel, it ...


3

It is possible that the freehub has become loose from the hub. Remove the axle and bearings from the hub. Insert a the correct size allen wrench (I believe a10mm) into the non drive side. Tighten the retaining nut. If hub continues to spin you may need to use two wrenches. One inserted in the free hub and one to tighten the retaining nut.


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