Another key component of the new Shimano 12 speed road drivetrain is the cassette. Not only is there one more sprocket, it now incorporates HG+ shifting, which provides fast and smoother outwards shifting. This feature comes from the MTB side where it is well appreciated by riders.
This cassette will be used on the Focus Paralane bike, to convert it from a 11 speed to 12 speed drivetrain.
How it looks out of the box. It has a cassette holder to hold the loose pieces together, and also make it easier for assembly to the freehub body.
Dura-Ace CS-R9200 12 speed 11-30T cassette weighs 223 grams, which makes it heavier than the equivalent 11 speed cassette with the same 11-30T gear combination (206 grams).
Tiny stamped arrows on the sprockets help you to align them on the freehub body.
Due to the need to squeeze in more sprockets to the same freehub body, the 11T and 12T sprockets have special splines that interlock with each other.
The new 12 speed cassette is compatible with existing 11 speed freehub bodies. In this case, not all splines will engage with the freehub.
Notice the empty gaps between the splines on the 12T sprocket? The 11T sprocket has small splines that engage at these areas.
Another view of how the splines of the new 12 speed road cassette is compatible with existing 11 speed freehubs.
The 11T sprocket basically engages with the 12T sprocket only and not directly to the freehub body.
There are two different types of spacers being used in this cassette, don't mix them up!
The thinner spacer is 1 mm...
...while the thicker spacer is 1.95 mm.
This aluminium cassette spider combines a steel 17T sprocket with a 19T titanium sprocket.
Another view showing how the splines are backward compatible to existing 11 speed freehub splines.
Even the inside of the aluminium spider is machined away to save weight!
The largest 4 sprockets (21-24-27-30T) are made of titanium and riveted together to an aluminium spider. No carbon fibre spider being used this time.
There is a thin adhesive ring that is glued onto the back of the aluminium spider, this ring will contact the end of the freehub body. Apparently the purpose is to prevent creaking sounds.
The riveting design on the 27T and 30T sprockets is rather clever. These sprockets are both riveted directly to the spider, and also to each other to maximize stiffness and strength.
Some cutouts on the 30T sprocket to save weight.
Pending the final 11T sprocket to be placed onto the freehub. As mentioned earlier, the 11T sprocket mainly engages to the 12T sprocket only.
The 11T sprocket on this 12 speed cassette protrudes slightly more than on 11 speed cassettes, it is normal. The 12 speed lockring is slightly longer to compensate for this.
All the gear spacing should look equal if the spacers have been used correctly.
As this 12 speed cassette has the same 11-30T gear combination as the previous 11 speed cassette, the gear range is exactly the same. Rather, the only difference is the addition of a 16T sprocket in between the 15T and 17T sprocket.
On the previous 11 speed setup, the 15T and 17T sprockets equate to the 7th and 6th gear respectively. Sometimes, I find myself switching back and forth between the 6th and 7th gear, as the cadence doesn't feel quite right, being slightly too low or too high.
With the addition of the 16T sprocket in between, this would serve to provide a sweet spot between the 15T and 17T sprockets, to let you pedal at your preferred cadence. This will be tested after the full bike is assembled.
I have a brand new R9200 11-34T Dura Ace cassette that is creaking ? Shimano was supposed to fix this problem with this new generating ? Apparently not !
ReplyDeletevery disappointing considering the heavy price tag .
Check if the thin metal shim is there behind the cassette.
ReplyDeleteyes it is there. I swap it for an Ultegra and no noise at all. I even tried it on another pair of wheels. They definitely did not solve the problem.
ReplyDeleteYou can trying adding a bit of grease at the contact points between the cassette spiders, and between the shim and freehub body. If the creaking sound is due to the cassette, this should solve it.
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