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SRAM Cranks Up The Boost with New Hubs, Cranks, and Wheels for 148 and 110mm Axles

Written by Zach Overholt
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SRAM_MTB_X0_Hub_Rear_Red_print

We first heard of Boost 148 when Trek unveiled the new Remedy 29. Sort of a soft launch, not much was really said about the new specification other than the rear hub was 148mm wide and it involved wider flange spacing for improved rear wheel stiffness. Now with the latest release from SRAM, Boost goes from a specification on a single bike to what they are calling an open platform that will offer performance benefits not just for the rear wheel, but for the frame, fork, and front wheel as well.

What is an extra 6 mm for the rear and 10mm for the front of the bike really going to do for you in the long run? SRAM claims that built with the same spokes, nipples, and rim, a 29″ wheel built with the Boost spec will offer the same level of stiffness found on a 27.5″ wheel built to the previous 142mm hub. The same can be said for the front wheel with a 29″ wheel laced to a new 15×110 mm hub carrying the same stiffness of a 26″ wheel built with a 15×100 mm hub. The wider specifications will also allow for improved tire clearance allowing for that coming wave of 27.5+…

 

sram boost 148 chainline dimension 2 3sram boost 148 chainline dimension 110 front hub

sram boost 148 chainline dimension sram boost 148 chainline dimension 2j

Rather than just a new size for rear hubs, SRAM refers to the entire package of rear hub, crank, and front hub and fork as Boost. By moving the flange spacing and hub spacing outward on the rear hub the Boost 148 design makes for a stiffer wheel, but that comes with a change in chainline. In order to keep the chainline in check SRAM will be offering Boost specific cranksets that add 3mm to the chainline to bump it up to 52mm. According to SRAM, Boost 148 rear hubs must be used with Boost cranks, and vice versa. While the chainline has been boosted, the Q-factor remains the same since the chainring is the only part of the crank that gets relocated.

SRAM points out that the move to 1x drivetrains with XX1 was always a part of their vision to add more space around the crankset for frame designers. Moving the chainline out from the frame’s center is the next step and should allow for bigger tire clearances, wider suspension pivots, and even shorter chainstays not to mention the ability to run bigger chainrings in certain cases.

SRAM_MTB_XX1_Crankset_DM_ChainRing_Side_Red_MH

SRAM_MTB_X1_Crank_1400_Black_MH

Boost cranksets will initially be offered in the SRAM XX1 and X1 1400 models with a 24mm spindle only. Both cranksets utilize SRAM’s X-Sync tooth profile with direct mount rings for XX1 and 4 bolt 104 BCD for the X1.

XX1 CRANK

  • X-SYNC™ tooth profile provides maximum chain control
  • Carbon arms with forged aluminum spider
  • CNC- X-SYNC™ Direct Mount ring
  • BOOST option
  • Wide/narrow Q-factor cranks for BB30 and GXP

X1 1400 CRANK

  • X-SYNC™ tooth profile provides maximum chain control
  • Hollow forged aluminum arms with forged aluminum spider
  • Chain ring guard option
  • BOOST option
  • CNC – X-SYNC™ machined ring

Boost Wheels and Hubs

SRAM_MTB_ROAM_40_Rear_Dynamic_Silver_MH SRAM_MTB_ROAM_40_Front_Dynamic_Silver_MH

SRAM_MTB_MTH_746_Rear_Disc_11sp_Hub_M

 

As for the rear wheels and hubs, Boost technology will be available with the SRAM ROAM 40 wheels, and the X0 and new MTH 700 hubs. The Taper Core aluminum ROAM 40 wheels are UST Tubeless and come with the SRAM Double Time hubs that are convertible to any axle type with XD or 10 speed driver bodies. Boost compatible ROAM 40 wheels (12×148 and 15×110) will only be available in 27.5 and 29″ models which makes sense as we don’t expect to see any 26″ bikes with the new specification any time soon.

SRAM X0 hubs will be offered in 32 spoke j-bend hubs in 12×148 and 15×110 with XD or the 8/9/10 freehub body. SRAM is also introducing a new affordable hub for thru axle bikes that will be compatible with the latest Boost specifications. Called the MTH 700, the 32 hole hubs will come in around 170g for the front and 410g for the rear, and be available with XD or 8/9/10 freehubs.

ROAM 40 WHEEL

  • Lightweight aluminum rim with asymmetrical TAPER CORE™ profile—with a welded joint
  • UST tubeless
  • User-friendly SOLO SPOKE™ technology
  • Durable, precision-machined SPEEDBALL™ bearings
  • Strong, fast engagement with DOUBLE TIME™ hubs
  • Available in all three wheel sizes
  • BOOST 12×148 and 15×110 options available for 27.5″ and 29″
  • Convertible to any axle type
  • Available in XD™ or 10-speed driver body
  • Color: Black/Silver

X0 HUB

  • Tapered aluminum axle is stronger without added weight
  • All axles types
  • 32 spoke holes
  • BOOST 12×148 and 15×110 options
  • Sand-blasted black with red label
  • Glossy black with silver accents
  • 11-speed XD™ Driver Body
  • 10-, 9- and 8-speed driver body
  • Weight: 130g (front), 250g (rear)

700 SERIES HUB

  • 32 spoke holes
  • BOOST 12×148 and 15×110 options
  • Black
  • 11-speed XD™ Driver Body
  • 10-, 9- and 8-speed driver body
  • Weight: 170-410g

SRAM_MTB_X0_Hub_Front_Red_print

All of the mentioned hubs and wheels will include a Boost front hub that will be compatible with the updated 15x110mm axle size. We’ve already gone into detail on the new size here, but the thinking is the same as for the rear with the wider hub offering improved stiffness and additional tire clearance. As an update for MY16, RockShox will be updating some of their most popular suspension forks like the SID, REBA, and PIKE to allow for the wider hub spacing. SRAM also points out that all 29″ Boost compatible suspension forks will fit 27.5″ x 3.0 tires.

Pricing and Availability:

sram boost 148 options

 

The chart above illustrates which SRAM and RockShox products will be compatible with Boost and their intended use.

sram boost 148 options pricingsram boost 148 options pricing 2

 
Zach Overholt
5,726 articles

Zach Overholt is the Editor in Chief of Bikerumor. He has been writing about what’s new in the bicycle world for 12+ years. Prior to that, Zach spent many years in the back of a bicycle shop building and repairing nearly every type of bike, while figuring out how to (occasionally) ride them.

Based in Ohio, Zach is now slowly introducing a new generation to cycling and still trying to figure out how to fit the most rides into a busy schedule as a new dad.

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gringo
gringo
9 years ago

The thing I HATE about the bike industry is that like 7 total Product Managers who are all way past their riding prime and desperately clinging to their careers by doing something ‘innovative’ get to decide that, for example all of a sudden 142 rear ends and all related parts are obsolete.

And to anyone who says vote with your wallet, it’s not that simple. German BIKE magazine will test Boost wheelsets and find they are a little bit stiffer, and will then rate all bikes with ‘old standards’ as cut rate technology., and then 142 holdouts will also change for next season. The old PM’s will sit in a circle with the even older sales managers and have a wank while shops and consumers get stuck with the bill.

The process will repeat itself in approx 3 model years’ time.

Thanks for nothing!

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randall
randall
9 years ago

@Gringo LOL! “Obviously stiffer than the “old stuff,” however, this must be so when the new standard increases the spacing!” They might also add something like “Also it is obviously easier to build a stiff chainstay with the generous three extra millimeters of available shell width…”

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craigsj
craigsj
9 years ago

“…Product Managers who are all way past their riding prime and desperately clinging to their careers…”

gringo, you must be a child. The only people force to “cling to their careers” once past their “riding prime” are athletes.

If Boost’s additional flange spacing is such a technical win, why aren’t the flange spacings of these hubs provided in this article? I’d like to compare them to existing hubs, not just assume they are wider.

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werstrider
werstrider
9 years ago

so if im still running 135/100 qr front and rear am I know considered a retro grouch or just poor?

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Alexander D
Alexander D
9 years ago

150mm with equal flanges is already available. With 1mm of play at both sides fitting a 150 wheel should not be a problem (IMHO).

Also chainline is only an issue in 1 of the 11 gears. And probably more of an issue in the lower gears where there is more torque (for the average rider). So a better chainline in the top 6 gears is more important than the other 5. 150 and 51mm chainline seems to solve all the “troubles”.

Who is the first builder who makes 150 XC frames?

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Ilya
Ilya
9 years ago

@werstrider if your wheels are 26″ with straight steerer tube, then your are retro fan; if it’s 29″ and tapered, then yes – you are poor because no cutting edge modern hardware.

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Patrick
Patrick
9 years ago

Yes, I’m a retro fan/grouch and not poor!

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gringo
gringo
9 years ago

@craigsj
Indeed, that statement does not read as I intended, please excuse me.

What I am trying to illustrate is the fact that when you have a 49 year old product manager with 5 kids, 3 cars, 2 houses and a desire to stay relevant in his job, the result is Boost.
Family commitments mean no week long enduro race in France, no downieville, no gravel grinder in Kansas. The guy rides mostly at lunch. His riding partners are also post middle age ( not the tip of the spear), and he only interacts with Taiwanese parts makers who tell him ‘ what the next big thing’ is going to be. He only reads bike magazines, and websites like this one. He can’t really ride fast anymore, but he has been doing this so long he knows where all the weak spots are left to tweak and sell as ‘NEW!’ The guy has not paid for any bike parts in more than a decade!
I am saying a lot ( not all) of the product managers are out of touch with you, the rider and your wants and needs.
You see, its an endless quest of out doing the competition ( on paper) for the sake of the magazine review. If more companies were focused on truly making quality, well riding bikes instead of chasing weight and stiffness numbers we would not be having this conversation.

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Matt
Matt
9 years ago

I like my 10 speed drivetrain. I like my 135mm travel. I like my disc brakes. I like my 27.5″ wheels. I like all the things that made each of my prior bikes obsolete. I like the idea of owning a bike with wider axles.

I like progress.

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phil
phil
9 years ago

I think a wider hub makes sense specifically for larger size bikes, larger wheels, and larger people. I also think 90% of people who buy mountain bikes are not capable of pushing it hard enough to feel the difference in stiffness regardless of setup.

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scott
scott
9 years ago

My car has boost about 18psi of it. My bikes will stay boost free.

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JoeP
JoeP
9 years ago

What it really looks like to me is that SRAM couldn’t get people to move fast enough to 11speed 1x super proprietary hubs faster enough – for more money than people were willing to pay so they decided to jump on the new Boost bandwagon and now push a standard that makes ALL the “older” after market parts even more obsolete and force the next upgrade to require that I now ditch my parts completely.

Lets see:
* 35mm new stem standard
* 35mm new handlebar standard
* which ever new BB standard of the week – wait are we going back to threaded again?
* 135, 142, 148, 150 wait which rear hub spacing do I need again?
* Front hub 110, 100 back to 110? What?

Ugh….

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substance
substance
9 years ago

gringo- you actually seem like you’re just trolling.

New stuff doesn’t make your old stuff obsolete. If you like it, nobody is forcing you to buy anything new. I work at a shop, I’ve mentioned before that shops like new stuff because people who really like bikes spend money on them.

If I can still order cotter pins for a 50 year old gitane, I don’t think you’ll need to worry about getting 142 hubs, 26″ tires, and anything else your bike might have on it.

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mateo
mateo
9 years ago

Don’t blame SRAM. Blame Trek and the other bike makers.

You can blame SRAM for XD driver bodies if you’re against 10 speed cogs though.

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Tom
Tom
9 years ago

It seems a little odd that a rear XD hub will cost $364, when an entire rear wheel goes for $380.

Did I misread something?

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Nate the PM
Nate the PM
9 years ago

@Gringo

So to summarize your opinions:
1. All PMs are old, boring, and don’t know as much as you do
2. A young PM couldn’t have possibly come up with this because it’s useless
3. Every technical innovation is useless because it was invented by someone who makes money
4. Technical innovation didn’t get us to where we are today with the sport so we should just stop it
5. You should be the sole dictator of what is useful new tech and what isn’t

You opinions on technical innovations are yours but your age discrimination only shows the rest of us how inexperienced you are. The best rider I know (and I know some good darn riders here in CO) is a 55 year old doc with 3 boys. He could smoke 98% of riders on any trail on any bike. Get a clue.

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Pete
Pete
9 years ago

not sure how they are listing conversion parts. when the hub its self is getting wider?

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thesteve4761
thesteve4761
9 years ago

@Gringo- Pay a visit to a relevant MTB company. I guarantee the majority of their PM’s will kick your a** up and down the trail.

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mateo
mateo
9 years ago

@ Tom – The X0 hub is nicer than what comes on the Roam40 wheel. Look at the price for the 746 hub.
@ Pete – What conversion parts? Boost hubs aren’t convertible to any other (current) standard

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Robert
Robert
9 years ago

people keep talking about the 150 standard… thats not anything alike the 148…

the 150 is the same cassette offset as the 157 just doesnt have the extra material to fall in to a dropout… they dont got to the 150 because then you would need the 83mm bb shell….. super wide Q
its kind of like 135X12 and 142X12…. the drivetrain spacing is the same

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Jimborello
Jimborello
9 years ago

The only thing that will make me jump into this Boost thing is when you can fit a 12 speed cassette in there.

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Bill Broadley
Bill Broadley
9 years ago

Not sure why there’s so many boost haters. Things are evolving, there’s quite a few changes afoot:
* suspensions are impoving, especially the zero-air dampers that allow for most consistent performance under the harshest improvements.
* materials and design are improving, today’s enduro/all mountain can handle terrain/riding styles that unthinkable on anything but a downhill bike a few years ago
* Wide carbon fiber rims are helping increase tire volume without a weight penalty
* Suspension travel is increasing at all types of bikes.
* Wheels are getting larger (27.5 and 29″).
* single chain ring bikes are becoming very popular freeing up the traditional very tightly packed (by 3 chain rings, suspension pivot, chain, deraillure, and 5 frame tubes) bb area.
* tires at getting wider

All of this is increasing the pressure on current hubs, spoke tension, chainline, and rims.

Boost sounds pretty good, sure it’s incompatible, but nobody is forcing you to replace all your gear this year. The benefits:
* much easier to support 27.5+ standard (wider tires)
* easier to support wider rims (thus higher volume tires)
* Stiffer/low friction pivots (it’s easier to make a wider pivot without play).
* Easier handling of additional suspension travel
* Stiffer and stronger wheels (giving 26″ wheel stiffness to larger 27.5 and 29″ wheels)
* less chainline issues (which restricts tire width, pivot/linkage width, and frame width)

Who doesn’t want a generally stronger and stiffer frame? Better suspension pivots? Stronger/stiffer wheels? Ability to run larger tires?

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Snlick
Snlick
9 years ago

Sounds good to me. 135mmx10 standard is pretty old these days. Thing about how much things have changed. Increased suspension travel, tire widths, lighter weight materials, etc. One of the most difficult engineering challenges on a dual suspension bike was to handle all the conflicting demands for the bottom bracket:
* 5 tubes (2 chainstays, BB, seat tube, and down tube)
* 3 chain rings
* a pivot
* fair bit of stress force both from suspension and pedaling
* Minimizing q factor (distance between the pedals, higher q = less comfortable/efficient to pedal)
* resisting ground strikes, chainring hits, and the chain falling off.

Now rims are getting wider (see the ibis 741 wheelset, derby, and many others) and 1x transmissions (1 ring instead of 3, no deraillure or mount) have really freed things up. Carbon rims have remove the weight penalty for wider rims, and wider tires are becoming more popular.

The 135mm hub standard is pretty old, goes back to the 7 speed days! 142×12 mm doesn’t improve on 135mm as far as wheel strength or needed spoke tension on the drive side. Now with a 1x transmission, all the extra room, suspension travel getting longer, tires getting wider, why not take advantage of some of that space?

Mountain bike rear hubs used to be a nightmare. 10mm axles, quick release, and the bearings far inboard because of the cassette made them quite fragile. 12mm helps some, but the biggest help was switching to a freehub. That allowed moving the axle bears much further out. Thus a wider base to handle rear wheel loads.

An extra 10mm up front and an extra 6mm out back sounds good to me. Stiffer frames (because of the pivots), stiffer wheels, less spoke tension on the drive side, and no penalty in the q factor.

Seems kinda silly to say, yeah, we are going to stick with the engineering decisions from way back when hard tails weighed almost 30 pounds, 26″ x 1.9″ tires were the standard, and 3×7 transissions where the norm…. just because that’s the way they did it a decade or more ago.

Personally I’d welcome the ability to run wider tires and wider rims when conditions justify it. Stronger and stiffer wheels sounds like a big win, it’s only the width between the center line of the wheel and the hub flange that makes the wheel stronger. Why would you be against making a 27.5 or 29″ wheel as strong stiff as a 26″ using the old standard. I’ve had my share of pivot problems (original blur and blur lt), seems like using the extra width in the bottom bracket and pushed out chainline could help quite a bit.

I think many current bikes would allow wider tires, but it become infeasible using the current standard because of bb and chainline issues. A simple fix with little if any weight penaly sounds great. My blur LT barely handles a 2.1″, the new 27.5″ + standard handles up to 3.2″. Sure I might never buy a tire that wide, but ability to pick instead of being limited would be nice.

New bikes like the Bronson, Nomad, Norco Range, and similar all mountain/enduro bikes often are limited by 2.5″ tires, and even then, they don’t promise clearance. Why not have some benefit from using a 1x transmission in the form of larger tires, larger pivots, and stiff wheels?

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Alexander
Alexander
9 years ago

Wider hubs (or flanges) are nice. Also I can see that 1x etc will create more room for frame construction.

But why create a standard when current stuff wil do?

Going from 148 (141) to 157 (150) will create a chainline that is 4,5mm more outboard. So from 52 to 56,5. The chainline of the outer ring on a surly triple is 58,4. On the double a 59,2! So changing to 157 rear and just making different spiders/cranksets would solve all this trouble with less hassle for consumers.

Also in this age of 1x setups and 11 speed cassettes chainline is moot. And needs to be more inward because of the higher torque on the bigger sprockets. At least in my opinion.

Going to 83MM will create even more room for suspension etc. So in a few years get ready for Boost plus! 148 plus 83mm. More stiffness! And a few years after that 83mm plus 157 for the ultimate in stiffness.

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James
James
9 years ago

We should have gone to 150(7) rear ends when DH bikes did in the 90s. All these incremental half-measures are nothing but planned obsolescence destined to piss everyone off.

Just get to it so we can build frames around some stable numbers already. Tired of all this fooling around.

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SnidelyWhiplash
SnidelyWhiplash
9 years ago

I am quite happy with my 100 x 135 spaced frameset. I upgraded the hubs to accept 9&10mm thru axles, http://www.dtswiss.com/Components/RWS/RWS-Thru-bolt-en and that stiffened everything up fine for me. Endlessly chasing the supposedly latest and greatest tech is mostly a waste of time and money. Have at it if it makes you happy but as other commenters have said: most riders will not notice the difference.

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chilidog
chilidog
9 years ago

You’re hanging out with the wrong PMs @gringo.

Every product manager I know is smart & fast. I wish I could go on the riding trips they do.

Alas, perception is reality. If you were Jared Graves, product managers are slow and don’t get out much.

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Leonard
Leonard
9 years ago

get a fat bike frame. 150mm front hub and 190mm rear hub spacing. your hub will be future proof for the next 20years. unless 36in wheels becomes the norm.

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