28
votes
Why do freehub and cassette have only one position that matches?
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 ...
- 81.8k
20
votes
Accepted
Freehub pawl system vs star ratchet system
Hope hubs are a very refined, reliable execution of the pawl design. They don't do much to illustrate the disadvantages of the concept that designs like the star ratchet are trying to address.
One ...
- 81.8k
18
votes
Why am I getting no power when I pedal?
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" ...
- 2,361
17
votes
What freewheel mechanism designs are used in bicycles?
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 ...
- 1,981
12
votes
What freewheel mechanism designs are used in bicycles?
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 ...
- 1,981
11
votes
What freewheel mechanism designs are used in bicycles?
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 ...
- 1,981
10
votes
Accepted
What's the difference between Shimano HG and SRAM XD free hubs?
The phrase missing here is 'Freehub body'. The freehub replaced the freewheel, mostly, which integrated the sprockets and the ratcheting mechanism. The freehub body is therefore the ratcheting ...
- 4,170
10
votes
Accepted
Swapping Ultegra cassette 11-34 for 11-28: spacers?
There are two kinds of common 11-speed Shimano hyperglide cassettes.
The first type of cassettes, "MTB", has a big sprocket that is large. The big sprocket is shaped so that it overhangs the ...
- 18k
10
votes
Which Shimano Freehubs can I use on the WH-R550 wheel?
Shimano provides good official guidance about what the right part is and no guidance about what can be substituted. From the publically available exploded view diagram we know the matching part is Y-...
- 81.8k
9
votes
What freewheel mechanism designs are used in bicycles?
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 ...
- 1,981
9
votes
Accepted
Is there a difference of spacing between cogs on a 7 speed cassette vs a 8 speed cassette?
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 ...
- 81.8k
9
votes
Is there a roadside workaround for a freehub that won't engage reliably?
Use strong cable ties or wire/cable to tie the biggest sprocket to the rear wheel spokes. This will eliminate the freewheel, so be very careful when slowing down or going downhill.
If cable ties are ...
- 26k
9
votes
Can I put a different manufacturer’s freehub body on my hub?
There are two parts to this question.
Generally, you cannot swap freehub bodies between manufacturers. There are some exceptions to this (some hub manufacturers use DT Swiss hub mechanisms, so there ...
- 29.2k
9
votes
Accepted
Does a z-shaped cone wrench exist?
No, its not not needed. Remove the cone from the non-drive side, and the axle slides out the drive side. Assembly means setting the position of the drive side cone and locking it with the lock nut, ...
- 49k
8
votes
Servicing a Vuelta XRP Disc Hub
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 ...
- 81.8k
8
votes
Accepted
Why am I getting no power when I pedal?
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 ...
- 15.6k
8
votes
(Apparent) chain slippage causes on new bike - usual culprits already eliminated
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 ...
- 81.8k
8
votes
Accepted
12 speed cassette touching spokes
Sounds like the easy solution is going to be get an extra long lockring. Wheels Mfg and another company I can't remember both used to offer them. I believe current Chris King ones are longer than ...
- 81.8k
8
votes
What's the difference between Shimano HG and SRAM XD free hubs?
SRAM's XD and XDR drivers (their term) don't have splines, unlike Shimano and Campagnolo freehub bodies. Instead, their cassettes screw onto the threaded section of the driver as shown in the image ...
- 29.6k
8
votes
Accepted
Cassette with more gears on same wheel?
Since current >7 speed cassettes have so fine spacing between the gears, about the only reason why you'd want to install a cassette with more gears is wanting to get more range.
A 9-speed freehub ...
- 18k
8
votes
Accepted
How to achieve a 200 Nm tightening torque when installing a freewheel body?
Shimano's torque ratings are best interpreted as a "ballpark" in the extreme high and low ranges. It's only the 2-20Nm range or so where you should respect the precise numerical value. If ...
- 15.5k
8
votes
How to achieve a 200 Nm tightening torque when installing a freewheel body?
You could measure your lever length and put known weights on the end.
Clamp the tool to a vise in a way that the wheel is upright. If your wheel has a 311mm radius you now need to put a 50kg to 65kg ...
- 26k
7
votes
Accepted
What tool do I need to remove this Joytech freehub?
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 ...
- 81.8k
7
votes
Could I replace a hub on a wheel?
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 ...
- 75.5k
7
votes
Could I replace a hub on a wheel?
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 ...
- 121k
7
votes
Accepted
Is Shimano the only company with a sealed ratchet mechanism in their freehubs?
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 ...
- 171
7
votes
Should the tightness of the QR skewer (rear wheel) affect the freewheel
You just noticed that quick release tightness affects the bearing preload.
If your hub has cup and cone bearings, you can adjust the bearing preload so that you are able to tighten the QR skewer to ...
- 18k
7
votes
Accepted
How do I remove the rear sprocket from a Gates Belt drive system
It's probably stuck because it's digging in to the freehub body splines.
Install just the lockring without any spacers. Use your cassette lockring tool to immobilize the freehub from turning, and use ...
- 81.8k
7
votes
Accepted
How do I get off my totally stuck freehub body?
Just to be clear, the part shown on your pictures is called a freehub body (black cylinder with splines). It incorporates the ratchet system enabling the hub to engage one way and to disengage the ...
- 4,111
6
votes
Accepted
What is this cogset body?
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.
- 46.1k
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