Saturday, October 12, 2013

Chris King R45 11 Speed Rear Hub + Partial Disassembly

When you have upgraded every conceivable part of your bike, sometimes the only way to continue upgrading is to change out a previous upgrade. Re-look at all the previous upgrades that you have, and see if it is possible to "re-upgrade"!

I have been using the Wheelsport wheels for slightly over two years, ever since I brought back a pair of them back from Taiwan. As far as I know, it was one of the first pair of Wheelsport wheels that are used in Singapore, as I got the wheels even before MyBikeShop brought them in. After two years of usage, it is safe to say that these wheels are pretty good. I have had zero problems with these wheels over this time, and the rims are still as true as the day when it was first installed on the Dahon Boardwalk. It is also quite obvious that Wheelsport wheels are becoming really popular on Dahon and Tern bikes.

Of course, routine maintenance will go a long way in ensuring that the hubs run nicely and properly. I have been overhauling the rear hub freewheel mechanism every 6 months, cleaning and regreasing the moving pawls. For more details about Wheelsport Rear Hub maintenance, refer to this link.

However, I felt that it is time to try something new. I wanted to get a new wheelset, but I can't seem to find a wheelset that is better than the Wheelsport wheels. Short of the Kinetix Pro, which are light and fast but probably less durable, there are not many other options. Carbon or high profile wheelsets may look good, but they are actually quite a bit heavier and do not suit my style of riding. The only way to go is to custom build a new wheelset!

I see no advantage or improvement in rebuilding a wheelset with a 10 speed rear hub, as it will be not much different from my current wheelset. With top end groupsets progressing to 11 speed drivetrains, it is necessary to upgrade the rear hub in order to fit the wider 11 speed cassettes.

For Shimano 10 speed road cassettes, a 1mm spacer is needed to fit it onto a standard 8/9/10 speed freehub body.

1mm spacer on a 8/9/10 speed freehub body, for installation of Shimano 10 speed road cassettes

As for the new Shimano 11 speed road cassette, it is actually 2.85mm wider than a Shimano 10 speed road cassette. This means that even without the 1mm spacer, the freehub body will need to be 1.85mm longer in order to accomodate the 11 speed cassette. This is why all the new 11 speed compatible freehub body are 1.85mm longer than the current 8/9/10 speed freehub body.

Although I have no plans (yet) to upgrade to an 11 speed system, it is always good to future-proof, to allow upgrading in the future with lesser effort. There are actually quite a number of 11 speed compatible road hubs out there, but good hubs are hard to come by. In my opinion, American Classic hubs are really smooth, which are those used on Kinetix Pro wheels.

However, for gold coloured 11 speed road rear hubs, good ones are only available from Chris King or Hope (as far as I know).

My personal impression of Chris King hubs are that they are super durable, and have a unique RingDrive mechanism for freewheeling, instead of the common pawl and ratchet system. The freewheeling sound is also supposed to be a rather unique "angry bee" buzzing sound. Moreover, the hub engagement is much faster than most other hubs due to the RingDrive construction.

As for Hope hubs, they are using a standard pawl and ratchet freewheeling mechanism. They also have a super loud freewheeling sound, which I don't really like as it is too loud! They are cheaper than Chris King hubs though.

In view of the special RingDrive mechanism in Chris King rear hubs, I decided to get a Chris King try out this mechanism. I wanted something different from the standard freehub mechanism.

 Chris King R45 11 speed Rear Hub! Gold colour, ceramic bearings, 24 spoke holes.

The Chris King R45 rear hub has 45 points of engagement in the RingDrive mechanism, which means that there are 45 contact points between the freehub body and the hub shell when you pedal. This ensures firm power transfer with no slippage.

Also, this means that when transiting from freewheeling to pedaling, the hub has 45 chances to engage in a single rotation. To put it simply, the hub will engage every 8 degrees of hub rotation. (360 degrees divided by 45 = 8 degrees).

As for the Wheelsport rear hub, it has 24 ratchet teeth, and 6 pawls. There will be at most 6 pawls in contact when pedaling hard. The engagement angle is also larger, at 15 degrees. (360 degrees divided by 24 = 15 degrees. This means that there will be almost twice as much freeplay in the Wheelsport rear hub as compared to the Chris King R45 rear hub. It will not matter to most people, but I would like to try and see if the difference is perceptible.

Enough of all the technical info, let us move on to the pictures!

Rear hub that comes with a detailed servicing manual. 5 years warranty on the Chris King hub.

Opening a present!

Lustrous gold hub with laser engraved details.

The 1.85mm spacer that is used when mounting 10 speed cassettes. For mounting a Shimano 10 speed road cassette on this freehub body, use both the 1.85mm and 1mm spacer.

Hub needs to be readjusted to remove any bearing play after a settling-in period. This is because angular bearings are used in this rear hub.

Aluminium freehub body, lightweight but less durable. Something I overlooked when doing my research.

I realised that the freehub body is actually made of aluminium, which keeps the weight down but will be more prone to damage by the steel sprockets. This will be of problem to powerful riders or MTB riders who will mash the pedals hard. My riding style is more of spinning nicely and comfortably in the correct gear, which will hopefully minimise the damage to the aluminium freehub body.

Before building the hub into a wheelset, I decided to take apart the hub to check out the mechanism inside. With the help of the manual and some Youtube videos, it seemed quite doable.

Dismantling the Chris King R45 Rear Hub (Partial):

Loosen the 2.5mm hex bolt on the non-driveside. This bolt tightens the adjusting clamp around the axle.

Use the so-called "helper hole" to help unscrew the clamp. Insert the 2.5mm Allen Key into the hole and use it to help unscrew the adjusting clamp.

After loosening the clamp, the non-driveside QR insert can be pulled out. It can be rather tight due to the rubber o-ring and the close tolerances of the hub.

The inside of the adjusting clamp. See how the material use is minimised, by hollowing out the parts that are not needed!

Once the adjusting clamp has been removed, the entire axle can be pulled out from the other side. It is really simple!

The freehub body, otherwise called Driveshell Assembly by Chris King. Note the helical thread that is part of the RingDrive mechanism. Also pulls out of the hub shell quite easily.

The inside of the driveshell, with the sealed bearings visible.

Close-up look at the helical gear. This activates the RingDrive mechanism when the freehub body rotates forward during pedaling.

Yup these are ceramic bearings! Further disassembly is possible if the bearing snap rings are removed.

The other side of the helical gear, which moves in the axial direction to engage the RingDrive mechanism.

The 5 sub-assembly parts of the Chris King R45 rear hub.

I am happy that this basic disassembly can be done with just a single 2.5mm Allen wrench! No need for other specialised tools. Of course, if we want to further disassemble the hub, special tools will be required. But for routine maintenance, this should be sufficient to clean and regrease the helical gears. As for maintenance of the RingDrive mechanism, special tools will be required to further disassemble the rear hub.

It is also quite easy to reassemble the rear hub, and I have also learnt how to adjust the bearing preload. Now all that is left is to build the wheel and use it!

Lastly, a picture for weight weenies:

Weight of 218.2 grams, which is practically the same as specified in the specifications (218 grams). That shows how accurate their manufacturing process is, to be able to control the weight down to the nearest gram. This can be considered a relatively lightweight road rear hub.


  1. Really interesting, please let us know how this hub performs in your daily rides.

    Thanks for sharing!

  2. Thanks for sharing.

    I am also interested to do the same but with Hope Pro 3 hubs instead.

    Can you help me with some questions?

    1. Which wheel size is this? 406 or 451?

    2. So you used your old wheelsport wheelset with 24 spokes?

    3. Where did you go to change hub to this Chris King R45 and how much wasthe cost of the labor?


    1. 1) I am using 406 rims on my Dahon Boardwalk. 451 is also possible on some frames.
      2) I did not use my old Wheelsport wheelset, I basically built a completely new wheelset with all new parts.
      3) The wheel was built by Gee Hin Chan, at a reasonable cost. $20/wheel for wheelbuilding, and $1 per spoke+nipple ($1.50 if the spokes have to be cut to length). However GHC is closing down so I don't think they still accept new jobs.

  3. Can I know how is the sound of the hub? I heard CK hub sound is loud and can irritate cyclist around you.

    1. It is really like a buzzing bee, as what most reviews say. However this road hub R45 is still OK as it has less engagement than the MTB version with 72 engagements, so it is not as loud.
      The freewheeling sound only occurs when you are not pedaling, so it is not all the time or that often. Some people like the sound while some like quiet hubs.

    2. Thanks Steve for the reply. I'm really torn apart between American Classic, DT Swiss and Chris King hub. If you can share any opinion on this it would be great as I value your opinion. Which one will you prefer to use?

    3. Each of those are really nice hubs. The Chris King hubs are the most expensive, but not necessary the best I think. My old Wheelsport hubs are smoother than this Chris King hub.

      If I had the chance to buy again, I would get American Classic with Ceramic bearings. They would cost less than the Chris King, but will be super smooth.

      Of course prices will differ. Chris King has the advantage in terms of colour, if that is an important factor for you.

    4. Thank Steve,

      Colour is an important choice for me but the good think is Black is my favorite hub colour so I can say I'm save with all 3 of them :).

      Cheers and thanks.

  4. Hi Steve,

    Nearly screw myself big time. Lucky I've not press on the checkout button :). In my excitement to purchase the hub I didn't check on the front hub. Just realized I cannot use the CK front hub on my folding bike.

    What hub are you using for your front? Are you using the default wheelsport hub?


    1. This is the front hub that I am using.

  5. Hi Steve,
    How many km rides before one needs to service the ck hub. Tks

    1. I have no idea about that. If used frequently, it would be a good idea to take it apart for cleaning once a year though, that is my personal feel.