Inside SRAM's 11-speed rear hub and XD Driver
SRAM had its XX1 rear hub with the XD ratchet driver on display at Interbike and we were allowed to field-strip it to show Pinkbike readers what was inside the eleven-speed-only assembly. DT Swiss and SRAM teamed up to produce the patented XD cassette driver. Now, says SRAM, the XD driver will be made under an open-license agreement by Mavic, American Classic and Crankbrothers, with more hub and wheel makers coming on board next season. The XD driver is necessary to provide clearance for the 11-speed 'X-Dome' cassette's tiny ten-tooth sprocket, which is too small to adapt to a conventional freehub. Presently, DT Swiss makes the XD driver and hub for SRAM, which means that it can be assembled without tools.
SRAM's rear hub can be adapted for standard quick release or a 142/12-millimeter through axle by simply interchanging endcaps. We asked SRAM to walk us through the 142/12 version. Begin by sliding the rear axle from the hub.
Pull off the endcaps and the XD driver can be slid off the hub's stub axle. The pawls will fall off the XD's ratchet mech, so watch out for loose parts. The ratchet ring and stub axle are shown on the left. SRAM uses oil instead of grease to lubricate the ratchet to maintain operation in freezing conditions. The protruding axle sleeve supports the outboard bearing of the XD driver.
A look at the XD driver's three-pawl ratchet shows the stiff, flat springs and the unique, three-tooth engagement on each pawl. Threads on the driver (right) engage a sleeve inside the eleven-speed cassette. The driver has two sealed bearings. The outboard bearing protrudes about four millimeters and indexes the driver into a sleeve beneath the cassette's smallest cogs.
The black-anodized sleeve can be seen inside the XD eleven-speed X-Dome cassette. Normally, the XD driver will be installed on the hub's stub shaft before the cassette is installed, but we wanted to show how the driver fits into the cassette (right). Like the X.0 cassette, all pedaling loads are carried by the splines of the largest cog. In the case of the XD drive, however, the larger indexing spline that is used on conventional freehubs has been eliminated, because the remaining ten cogs are machined from a single piece of stainless steel and it is not necessary.
A close-up look at the X-Dome cassette(left) reveals the black-anodized splines of its inner sleeve. The cassette simply spins onto the threads of the XD driver using a Shimano-type freehub lock-ring tool. The XD driver's outboard bearing is visible inside the cassette. In real life, you'll need to install the driver first (right). Slide the XD driver over the axle stub and then turn it counter-clockwise to engage the ratchet. The endcap then snaps onto the axle stub.
We discovered that SRAM's XD driver and hub system is quite simple to take apart and reassemble. Each part either slides into place, or snaps together. The threaded cassette sleeve is the only component that requires a tool and none are needed to switch the hub from one axle standard to another. This should be a plus for XX1 owners who ride in inclement weather, as regular maintenance of the driver and hub will be a painless process. The XD system is an elegant solution to adapt smaller cassette sprockets to a conventional hub design.
More info at SRAM
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Maybe?
It LOOKS trick, but that's not why I buy stuff...
Every time a new drivetrain comes out, the critics come out about how their current drivetrain is "fine". I remember the 8 speed whiners - "there is no mud clearance in their like my 7 speed!". Those riders are probably on 10 speed today.
Fortunately the manufacturers shine on these luddites and keep pushing the technology forward.
I'd rather see a gear box that is light and works more than anything though.
their drive train. Me too, and i stick with a company that builds derailleurs and not fishing equipment but so what!? You have to ride
the XX1 and feel the real difference. Its not about the +1 gear! Its about a simple drive train working with absolutely NO NOISE &
FAULTLESSLY. I ride 1x10, tried it and i choose to buy it no matter the cost because the feeling in the roots is like riding your
single-speed DJ bike in the pavement. I love mountain biking and i choose to follow new technologies.
p.s cheaper editions ox the XX1 will for sure follow.
big ring that large WTF whos stupid idea was that 38t max.. no need for a 42 t cassette even with a 36/38t chainring!!
with the small ring being a 10t rather than the standard 11 you could get away with a 34 chainring and still have the same downhill gearing as a 36
i rode my old 17 kg enduro style rig up xc climbs with a 36 chainring and a 9spd11-34 cassette, im no fitness fanatic!!! most downhill bikes these days weigh that !!!!
best options would be:
36 ring up front with 10-38
34 ring at front and squeze a 9-36 in with some narrower ratios than a standard 10 spd
if hope can fit a 9t small ring in im pretty sure sram could find a way to do it!!
good idea ruined by small niggles
RANT OVER!!
Why all the new hubs, derailleurs, chains and chainrings for a 10 tooth cog? I love my 10 speed setup but could run a slightly bigger chainring if I had a 42 in the back.
I am hoping they or someone puts out 10spd compatible rings with the fancy teeth so I can ditch the MRP 1.x and just get on with a Shadow Plus RD.
Springs look like made of stainless steel. Springsteel is correct material and weakens a 100x slower than ss. If they went for beefy ss: Lots of heat generated and power wasted.
Bearing looks good, like the axle release. Various axle dimensions not needed unless there is new 20mm back and 30mm front...downgrading not fun.
The rule of the game is: reduce cost and liveexpectancy of part, cover up with bling.
If you look at bike parts the way I do - I drool over great engineering not marketized product phantasies. 11 flimsy cogs and a (dare to be different for the sake of beeing different) ratchet mechanism doesn`t exite me. The production process to create a really strong Boobar handlebar - very inventive and much cleverer than the "more is better" approach of the gear department of sram. I like.
Hope use the spring pawl method & has worked fine for years. Other companies use multi tooth pawls to allow finer pickup. Again, works fine. Worst case they wear & you need to replace the pawls, looks like a 5 minute job. Even with typical spare parts rip off pricing I doubt would be very expensive.
Flimsy cogs? If you say so. No more than 10% thinner than 10 speed. Again, works fine, you don't hear of people ripping cogs off due to their massive leg power.
I actually really like the idea of 11 speed. I am running 2 x 9 and just couldn't see the point - or expense - of switching to 2 x 10. I would like to lose the granny & front mech/shifter but 1 x 10 doesn't give enough range(for me).
Whereas 11 speed could be the answer here. Granted it is a shame you need to buy like half a bike to swap everything over. But whatever, that's the price of progress, noone is insisting you do it.
You buy a new bike in 2013 you'll likely get this for the same price as the 2012 version anyway!
Good luck those who spend loads on first generation SRAM and realise when they need to replace the cassette they have either a warranty claim on their hands and time off the trail, or a big bill form their bike shop. (Which if they bought it in the first place, they wouldn't be unused to!)
I would guess that's all been thought of, however there's nothing to suggest otherwise. I've got 10 speed XT and after 2 years I've had to change a rear gear cable, I have SRAM X9 on my downhill bike which also works well. I just can't see the point in paying loads to compromise on tried and tested methods, when they don't seem to have a marked advantage.
Rant over!..... Each to their own... it does look very nice though etc etc.
Whereas 10 gives you the same spread, is more fickle, has a weaker chain, and costs a lot move for nothing. The only real advantage to 10 speed was that manufacturers could consolidate production with their road lines and save some costs, we haven't seen that passed on the consumer yet though, and likely never will.
Say what you will about 11 speed setups, at least it's something different and not a cash grab financed by the sheeple who upgrade because they're told to (or, granted, in many cases forced to because they purchase complete bikes and the manufacturers drank the kool aid).
As far a the strength of an 11 speed chain; your only shortening the pin length and the plates remain the same. So in theory, it should be stronger.
I9's fit your standard casettes - they are splined the entire length of the cassette body
I9 have six pawls, with one set offset so they are not engaged while the other set is engaged. This is why I9 has 120 POE, or if you remove one set of three pawls (ending up like the picture above) you'll get only 60 POE. Only.
Just an extra though to the chain issue, and i know it seems simple, but not all mechanics know and if between a load of them they can't set up a 10 speed gearset they could just be setting the chain up too short to accomodate chain growth under compression, which will then usually bend or break your mech hanger (you'll normally be in a low or 1st gear for this to happen) which may in turn put your mech into your back wheel and tear your mech off and bend some spokes or snap your chain.... can cause lots of problems.
May be worth checking. Shift into your lowest gear (on your biggest chain ring if you have more than one) and release all air from your shock / remove the coil and compress the rear end to the max. That'll tell you i your chain is long enough.
May sound like I'm teaching you to suck eggs, but given the other advice above it's the only other thing not on there.
PS I really like riding bikes.
personally i'm quite happy for this kind of development in bikes...thats progress....... but the wheel size thing is doing my head in, at least with a 29er you can say i gain this big advantage and lose out on another....whereas 650b....best of both worlds or worst of both worlds? and will it be an nth degrees of f'k all difference to one or the other previous sizes
OR - you have a lower granny for people who need it for high alpine riding or whatever - run a 34t and the 42t to be able to climb steeper terrain for longer than with a 334 36 setup - but still have a 34t to 10t for the downs.
System isn't needed by everyone but will be needed by some - the first showing of it at Crankworks it was used to win the enduro event there - maybe the guy would have won on a 1x10 but maybe it helped swing it for him - who knows.
I'm not too stoked that I need to buy a different hub or freehub for it however. I don't see the need for that 10 tooth anyway. Oh well it is what it is.
...and I'm not super well funded, but since I don't race MX anymore, the cost of mountain biking seems manageable even when buying all the best stuff.
11spd cassette
Rear Derailleur
Shifter
The cranks and chain are on the site too, I am sure 11spd prices will come down fairly quickly by the end of next year when more budget options come out.
... my 9sp drive-train is still going strong
You can choose from 20-something tooth to 36t chainrings on XXI groups.
I'm not very warm to the whole idea of just one chainring as I don't have the legs for it and 1 chainring would make me get short at either side of the gear range, but I can see it working for racing applications.
Then, I vaguely remember from my engineering days that less than 11t was not very good for roller chain systems, but I guess I should have put more attention to my teachers.
If I was an inventor I would put the money into different areas.
10t sprocket will not make anyone better biker. Keep the freehub body unchanged, stick with 11t and use slightly larger chainring on the front if you worry about your top speed and bus chase - much simpler and cheaper
www.oldmountainbikes.com/catalogs/ritchey/1997/1997RitcheyComponents.pdf
Seems like the 2x9 'revolotion' which still slowly in my opinion (at least in the low budget category) takes over the 3 ring setup, have been around since ... 1997, when most of us was still riding with the stabilizers
Maybe Chris King will adapt this so I can upgrade
to give you the viewpoint of a professional workshop manager in a high turnover bike store, my customers have had no more issue with 10 speed (in 3 x 10, 2 x 10 and 1 x 10 formats) here in the mudbath we call the UK, than with previous 9 speed systems
personally running SRAM X-0 in 1 x 10 on my 29er and no issues to speak of, feels just like my previous X-0 and X-9 in 1 x 9 setups in terms of durability
no offence was intended.
I would ask your mechanic take a serious look at your frame alignment, if you are having on going issues, 10 speed is no more difficult to set up than 9 speed. gear problems are often caused by poor frame alignment, crank installation spacing issues and slightly bent derailleur hangers (we get new bikes with slightly bent hangers!)
ask your LBS to run a Park dropout end alignment gauge over your dropouts, and also use the Park frame alignment gauge to check fore / aft frame alignment. Also, have them use the Park derailleur hanger alignment tool to check your mech hanger for up/down and left/right alignment (it can be slightly twisted as well as bent inwards)
if you are constantly braking chains, there is something wrong with either your drivetrain (have them carefully check your cassette, derailleur pulley wheels, chainrings for any abnormal damage (like a twisted tooth). Also, each time your broke your chain, was the new chain (or the broken chain fixed) using the same chain tool?
Often, a mechanic may use a chain tool without realising the driving pin is actually damaged, which causes the chain plates to flare during installation, soon leading to chain failure. The modern chains are extremely strong when fitted properly (braking strain of 850 kgf is typical), its usually drivetrain component damage or faulty fitting that will cause chains to keep breaking
finally, have a look at your cabling, for problematic gearing systems I always go for Shimano SP-41 cable outer and genuine Shimano inner gear cables with Shimano SP sealed gear caps, not cheap but worth every $$ as 90% of the time it cures shifting lag or mis-shifting that Jagwire, Clarkes, etc. cheaper cables will cause
big ring that large WTF whos stupid idea was that 38t max.. no need for a 42 t cassette even with a 36/38t chainring!!
with the small ring being a 10t rather than the standard 11 you could get away with a 34 chainring and still have the same downhill gearing as a 36 i mean best options would be:
36 ring up front with 10-38
34 ring at front and squeze a 9-36 in with some narrower ratios than a standard 10 spd
if hope can fit a 9t small ring in im pretty sure sram could find a way to do it!!
good idea ruined by small niggles
RANT OVER!!