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Monday, 25 October 2010

10 Speed (or 20, or 30)

 
The normal gear count when I started mountain biking in 2007 was 27. That means 3 on the front and 9 on the rear. We refer to it as 9 speed, as saying 'twenty seven' is mouthful, and perhaps also it sounds too newbie.
:)
 
Of course there are also 8 speeds and 7 speeds still lurking around, particularly on cheap complete bike offerings. There are also 8 speeds on old skool riders' bikes, on the grounds of being content with it and don't see the need for additional weight plus expenses.
 
In 2009 SRAM introduced XX drivetrain, the revolutionary 10 speeds on the rear cog of an mtb, with the 10 speed CNC cassette, X Dome, which borrowed their road bike cassette technology. It came with a better shifting chainring design, closer ratio gears, and overall groupset (with brakes and fork) weight lower than Shimano's XTR (3x9). However, the XX system is having only 20 gear count, with 2 chainring in front.
 
Recently, Shimano also joins in the mtb 10 speed bandwagon with their lineup of Dynasys system, also with 2- and 3-chainring setups. Take that, 30 gears now for mtb! Not to be left out, SRAM also replied with their line up of new X7, X9 and X0 with a choice of also 20 or 30 gears. Do note that both are still offering the 'normal' 3x9 option.
 
Well, it seems that the terms that we use for indicating the gear count would definitely have to be changed now. A 10 speed may mean 20 gears or 30 gears. If road bike gearing tech is to be an indication of things to come, what's next? 11 speed? Electronic controlled shifting?
 
I haven't tried any of the 10 speed system, thus I can't say anything much about it except for the system itself. The big question for now: do we need them?
 
It goes down to personal choice. Efficiency, weight and durability need to be balanced. Not to mention the initial amount of $ to be forked out for a complete drivetrain.
 
Of course, there's also an issue of incompatibility with other systems. Can SRAM's 10 speed parts be used on Shimano's equivalent? With the 3x9 system, drivetrain parts are interchangeable between Shimano and SRAM, except for the rear shifter and RD which need to be specific due to cable pull ratio. Furthermore, with Shimano's Dynasys, the chain is specific for 10 speed, and even the side of the chain needs to be installed correctly. To me, that's robbing away flexibility and it goes without saying that you're stuck with whatever they want you to need for your drivetrain.
 
The interesting part of this is that SRAM is offering the 10 speed lineup as a complete groupset now; hub, crankset and brakes now packaged as SRAM's X0, X9 and X7 in addition to their existing shifters, derailleurs, cassette and chain respectively. That's another story altogether.
 
What we are presented with now are choices. Or are we shoved with choices...? There are many configurations available for any of the setups, be it 2x10, 3x10, either from SRAM or Shimano. For instance, the cassette choices for X9 has 9 configurations, but perhaps 7 of them are from their road range.
 
Shimano's Dynasis:

XTR

XT

SLX

crankset

cassette

crankset

cassette

crankset

cassette

3x10

2x10

11-36

11-34

3x10

11-36

11-34

3x10

11-36

11-34

24

38

11

11

24

11

11

24

11

11

32

26

13

13

32

13

13

32

13

13

42

 

15

15

42

15

15

42

15

15

 

 

17

17

 

17

17

 

17

17

 

 

19

19

 

19

19

 

19

19

 

 

21

21

 

21

21

 

21

21

 

 

24

23

 

24

23

 

24

23

 

 

28

26

 

28

26

 

28

26

 

 

32

30

 

32

30

 

32

30

 

 

36

34

 

36

34

 

36

34

 
SRAM's lineup:

XX

X0

crankset

cassette

crankset

cassette

2x10

11-32

11-36

3x10

2x10

11-32

11-28

11-26

11-23

12-36

26

28

30

11

11

22

26

28

11

11

11

11

12

39

42

45

 

 

33

39

42

 

 

 

 

 

 

 

 

 

 

44

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

32

36

 

 

 

32

28

26

23

36

 

X9

crankset

cassette

3x10

2x10

11-23

11-25

11-26

11-28

12-25

12-26

12-27

11-32

12-36

22

26

28

11

11

11

11

12

12

12

11

12

33

39

42

 

 

 

 

 

 

 

 

 

44

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

23

25

26

28

25

26

27

32

36

 

X7

crankset

cassette

3x10

2x10

11-23

11-26

11-28

11-32

12-36

22

26

28

11

11

11

11

12

33

39

42

 

 

 

 

 

44

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

23

26

28

32

36

 
figures are from SRAM and Shimano websites
cassettes tooth count for SRAMs are unavailable
 
I'll stick for 3x9 for the time being, and waiting for the XX's X-glide chainring shifting tech to trickle down to their lower tier offerings.
:)
 
What's your drivetrain choice?
(Single speeders need not reply).
 
Thanks for coming over.
Have a good day!
 
p/s: now that they're moving into 10 speed, Shimano Alivio is now offered at 9 speed too.

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