# SRAM Hammerschmidt?



## MichauxYeti (Nov 10, 2005)

There's been some internet chatter the last few days about a new drivetrain system from SRAM, dubbed the Truvativ Hammerschmidt. Speculation suggests that it is a planetary drive system that would fit inside the envelope of a standard crankset and eliminate the need for a front derailleur. Does anyone have any more information on this regarding mounting provisions or frame building specs?

The only official information is at magicmechanics.com.


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## swift (Apr 3, 2007)

No specs that I know of yet but the prospect is exciting.

3spd crank + I-Motion 9 Internal hub = single chainline and 27spd internal gearing.

I hope the weight/cost/ratios are competitive/comparable with derailer drivetrains. If so, I predict single pivot bikes will likely come into favor given their simplicity, rigidity, and ease of maintenance. Goodbye derailers and chain tensioners. Goodbye to the "big companies" strangling the market with their hold on fancy four-bar pivot locations. Lots of potential here. ...We'll see.


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## Jerk_Chicken (Oct 13, 2005)

Single pivot bikes will always be in favor for many, and they haven't lost anything over the years. I don't think this would impact them at all.

As far as rigidity, single pivots are not as rigid as multi links, though there are exceptions to both types. There are manufacturers, such as Foes, using mini swing links to increase the rigidity of the single pivot suspensions and isolate the shock from side loads that can accelerate wear.


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## swift (Apr 3, 2007)

Jerk_Chicken said:


> Single pivot bikes will always be in favor for many, and they haven't lost anything over the years. I don't think this would impact them at all.
> 
> As far as rigidity, single pivots are not as rigid as multi links, though there are exceptions to both types. There are manufacturers, such as Foes, using mini swing links to increase the rigidity of the single pivot suspensions and isolate the shock from side loads that can accelerate wear.


I agree with most of that. ...Except the general statement about single-pivots not being as rigid as multi-link bikes. True there are always exceptions in either case. Pivot points are flex-points by nature. In general, I think the more pivots introduced, the more flex there will be cummulatively. It's also one thing to compare designs on a bike shop's showroom floor. It's another thing, entirely, to compare the same designs after 2K miles of hard, multi-season, singletrack abuse. IMO, an efficient drivetrain that can implement a single chainline will make overly complex multi-pivot bikes a niche' market. ...Both due to complexities/cost of manufacture and long-term reliability/performance. Is it coincidence that we don't see many four-bar type suspensions in the high "power to weight" world of motorcycles?

Perhaps we can both agree that it's an exciting prospect to have another compelling drivetrain make it's way to market? It will increase flexiblity in design and customer satisfaction. :thumbsup:


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## Mutantclover (Oct 1, 2006)

They just broke another hint. At Sea Otter "select journalists" got to try it out blindfolded on a trainer. They said the setup they rode could shift without pedaling, had two gears on the front that felt like a 23-34 tooth combo.

I am interested in this not only for dual suspension implications but mainly for my singlespeed. It would be so awesome to have a 23-18 and a 34-18 without inheriting any downsides besides weight and hopefully only a little resistance. Not that I really need it, but it would be great for slow technical areas. This was the first thing I thought of when I heard about this, but maybe that's because I don't have a dual suss...

edit: I might add though that the aforementioned SS just had its truvativ crank lose half an arm... not very impressive on truvativ's part because I always thought cranks snapping was just a story and would never happen to me (the other arm had signs of cracks forming as well) but I'd imagine they've already fixed this issue. The crank was at least 5 years old.


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## NEPMTBA (Apr 7, 2007)

Jerk_Chicken said:


> Single pivot bikes will always be in favor for many, and they haven't lost anything over the years. I don't think this would impact them at all.
> 
> As far as rigidity, single pivots are not as rigid as multi links, though there are exceptions to both types. There are manufacturers, such as Foes, using mini swing links to increase the rigidity of the single pivot suspensions and isolate the shock from side loads that can accelerate wear.


 More parts = More movement = More wear = More flex = More maintenance = More replacement parts... just like a chian with links they all share the load.


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## cocheese (Jan 12, 2004)

Mutantclover said:


> edit: I might add though that the aforementioned SS just had its truvativ crank lose half an arm... not very impressive on truvativ's part because I always thought cranks snapping was just a story and would never happen to me (the other arm had signs of cracks forming as well) but I'd imagine they've already fixed this issue. The crank was at least 5 years old.


Me too. This would be really cool if it would work well with an SS. The chainline shouldn't change if the design is like the Schlumpf. I saw someone mount a shifter on the seatpost around here. That would make for a setup with less cables running around and keep the bar clean and SS-approved.


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## Schmucker (Aug 23, 2007)

A company already has a two speed crankset. I can't remember the name. It starts with an "R."


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## Thylacine (Feb 29, 2004)

Please people, can we not be sucked into this thinly veiled and frankly boring corporate 'guerilla' marketing?

That includes you Mr.Michaux "Powered by Sram" Yeti.


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## MichauxYeti (Nov 10, 2005)

Why be a jerk? I'm no shill, I just like their stuff because it works. If you look back at the OP, you'll see that I was asking if there is any information regarding mounting provisions or other frame build specs.


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## pvd (Jan 4, 2006)

Gotta say, Thylacine is on to something. Everyone knows that the only thing good SRAM makes is forks these days. The cranks are sooo bad. They break all the time. Shimano cranks never bend or break. Why? Cause Shimano employs real engineers and does real testing.


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## Mutantclover (Oct 1, 2006)

I think SRAM has better chains, and I use twist shifters too. 

If it weren't for the whole snapping part the crank would've been okay. Well, I lied, I noticed the chainring bolts were junk too. I actually had to drill one out to salvage the ring and bash guard. (the Shimanos threaded on/off perfectly) Oh and the BB snapped in the middle prematurely as well. So yeah hopefully they have fixed ALL of these things which is why I'm not going to be the guinea pig for the Hammerschmidt.


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## Thylacine (Feb 29, 2004)

Why be an overly sensitive namby-pamby? This kind of marketing sucks donkey balls and having it perpetrated by fanboi's doesn't make it any more palatable.


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## shiggy (Dec 19, 1998)

Thylacine said:


> Why be an overly sensitive namby-pamby? This kind of marketing sucks donkey balls and having it perpetrated by fanboi's doesn't make it any more palatable.


I think you are the one being overly sensitive. Not every inquiry is a marketing ploy and I highly doubt that this one is.

The OP's use of a SRAM logo as an avatar or Yeti in his user name does not mean he has any connection with either company.


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## pvd (Jan 4, 2006)

Mutantclover said:


> I think SRAM has better chains...


Sure. Adding a 'weak link' to a chain is a real upgrade!?! Shimano chains don't have the weak link feature.


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## mjw (Feb 26, 2007)

pvd said:


> Gotta say, Thylacine is on to something. Everyone knows that the only thing good SRAM makes is forks these days. The cranks are sooo bad. They break all the time. Shimano cranks never bend or break. Why? Cause Shimano employs real engineers and does real testing.


I bent a set of XT's within the first couple of weeks of having them...two seasons ago, in a pretty low speed crash. So, never say never.


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## RoyDean (Jul 2, 2007)

pvd said:


> Sure. Adding a 'weak link' to a chain is a real upgrade!?! Shimano chains don't have the weak link feature.


Everyone I ride with uses sram power links, and I've never, ever seen one break. The "normal" links, yes... but never a power link. I've seen normal links break on a bunch of different chains, too.

Just because you don't like them doesn't mean they suck.


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## MichauxYeti (Nov 10, 2005)

Full disclosure: I ride a Yeti Kokopelli that I bought used. I like the bike because it performs well on my local terrain. It is equipped with SRAM X.0 drivetrain (old XT crankset), Reba fork, and Avid brakes that all work well for me. In my spare time I wrench for a pro mountain bike and cyclocross team that is currently sponsored by SRAM. However, I have a mind of my own and form my opinions independent of any marketing hype. I've seen good and bad from Truvativ. My wife hasn't had any problems with her Noir crankset. I helped a racer yesterday who's Stylo GXP crankarm fell off in the middle of the race. My suspicion (based on a decent bit of experience) is that it was an assembly issue as he cobbled the bike together from spare parts the week before the race and wasn't familiar with the spacer requirements behind the bottom bracket cups.

My interest in the Hammerschmidt is based on being a bit of a tech-geek and being interested in having other options available to use as a mechanic and soon-to-be hobby frame builder.

Thanks for sticking up for me, Shiggy.


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## buckoW (Feb 7, 2007)

pvd said:


> Gotta say, Thylacine is on to something. Everyone knows that the only thing good SRAM makes is forks these days. The cranks are sooo bad. They break all the time. Shimano cranks never bend or break. Why? Cause Shimano employs real engineers and does real testing.


I have play in 2 pairs of Saint cranks and no problems with OCT Holzfeller cranks. I think the Rock Shox forks suck. Never had a problem with power link and don't think mineral oil works at all for long descents.


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## ScaryJerry (Jan 12, 2004)

Ah who gives a sh!t if you're into Shimano or SRAM. They both suck equally. Everyone pick a side and we'll go have a tug-o-war or something.


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## pvd (Jan 4, 2006)

ScaryJerry said:


> Ah who gives a sh!t if you're into Shimano or SRAM. They both suck equally. Everyone pick a side and we'll go have a tug-o-war or something.


Poor baby.


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## ~martini~ (Dec 20, 2003)

pvd said:


> wwwhiiiiineee


Once again, your online persona is flaring up.

Differnt strokes for differnt there Peter.


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## xptxc (Feb 23, 2007)

Hi people, any updates on hammerschmidt ?


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## buckoW (Feb 7, 2007)

It looks sweet but the one I saw was only a non working show proto.


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## SuspectDevice (Apr 12, 2004)

There will be a medium weight and heavier weight model, both will be 2 speed (not 3), the unit mounts to ISCG tabs. For the brief time I've had on one, I'd say it's pretty neat...


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## xptxc (Feb 23, 2007)

Do you think that will be possible with this technology to have in the future 3 speeds?


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## wadester (Sep 28, 2005)

Well, I just caught on to this by accident - and why is it being discussed in frame building instead of drivetrain?

Anyhoo, the "other" non derailer front mech is the Schlumpf system (mountain drive - 2.5x reduction, speed drive - 1.65x, hi-speed drive-2.5x). http://www.schlumpf.ch/antriebe_engl.htm

They use a planetary gearset, and are shifted by a set of buttons at the crank axle actuated by your heels. Cool, work well.

They use a compression ring to put the reaction torque into the BB shell (have to chamfer it using rentable special cutter).

Hammerschmidt - requires ISCG mount, probably to take the reaction torque of the planetary gearset (shifts w/o pedalling - ooooh what a giveaway!)

So the Q's are:
What's the ratio? 
23/34 equiv says 1.5x, having 2 models (heavy/light) may be durability or wider ratio (bigger planet gearset)

What's the weight?
Schlumpf is 900g (HSD,MtD), 800g (SD) - w/o crank arms (180g ea)/rings (46t w bolts=90g) Total wt comes to 1350g/1250g. How much does BB/triple crank w rings/derailer/shifter/cables weigh?

What's the cost?
Schlumpf is about $500

Will they offer a non-ISCG adapter?


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## MK_ (Nov 15, 2004)

I wonder how similar it is to this system:
http://reviews.mtbr.com/blog/german-innovators-nicolai-bionicon-join-forces/

Too bad these won't bolt up to a standard 4-arm spider.

_MK


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## MK_ (Nov 15, 2004)

More detective work:









More details on Norco site.

_MK


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## [email protected] (Aug 10, 2008)

*Link to Press Release*

http://www.bikemag.com/news/freshpr...-unveiling-truvativs-hammerschmidt/index.html


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## phantom59 (Nov 17, 2006)

I just bolted one on my '06 Turner RFX. Installation wasn't anything special. I did have to take almost a mm off the drive-side bb shell face in order to get the Hammerschmidt backing plate to seat correctly on the ISCG tabs. As it turns out, the ISCG tab plate was very slightly off plane, so that my facing came to a stop when I found a reasonably happy medium between taking the bb shell too far in and leaving a slight ridge on opposite side of the shell. The unit shifts just fine, Other than also having to take a very minor amount of material off of the chainstay yoke to clear the backing plate, that's all I had to do. 
Apparently there is no cutter with a large enough diameter that fits normal bicycle-tool cutting handles to face this on the market yet.
The bike works great with the Hammerschmidt! From a frame builder standpoint, it would be imperative to align the ISCG plate/tabs perfectly perpendicular to the bb long axis, and to make sure that it was "clocked" correctly relative to the chainstays. The Turner works fine, but i could see if the tabs were clocked wrong, the HS chainguide would interfere with the chain or be useless, depending on the direction of rotation. I would guess that there is a range of arc that would be satisfactory. 

It would be great on a dirt jumper/urban bike. 1.6 - 1 overdrive for the Dirt jump park, then shift down to the 1 - 1 gear for street. Gear the back so you had a nice low gear for street/trials kinda stuff with pedal kicks, etc...then have the overdrive for hammering between jumps at speed or cruising to the next session spot.


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## Playdeep (Mar 18, 2005)

I am thinking about getting one for AM and FR. I have heard only great things from my buddies on their Highlines with this.


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## nicolacycles (Oct 17, 2008)

*Indifferent*

All i can add to this discussion is that I think this new front drive train technonolgy is extremely interesting, promising, and seems like a good direction to go for many different types of Mountain biking. I personally think some sub-groups of mountain biking will adopt this new tech with open arms as the new norm. It definately has its place and its about time.

When did front deraileurs ever work well?

As far as SRAM goes I have always loved the 1:1 ratio of their shifters. and F- Shimano for never collaborating when it comes to making standards.


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## gearphread (Apr 13, 2009)

wadester said:


> Anyhoo, the "other" non derailer front mech is the Schlumpf system (mountain drive - 2.5x reduction, speed drive - 1.65x, hi-speed drive-2.5x). http://www.schlumpf.ch/antriebe_engl.htm
> 
> They use a planetary gearset, and are shifted by a set of buttons at the crank axle actuated by your heels. Cool, work well.
> 
> They use a compression ring to put the reaction torque into the BB shell (have to chamfer it using rentable special cutter).


My Schlumpf mountain drive compression ring setup slips and spins under load. If you must have a Schlumf get the version with torque arm (ear) that connects to chain stay. I'll also recommend the steel spider version to increase your chainring mounting options. Schlumpf friction penalty far exceeds the weight penalty.

Don't buy into the equal torque math perpetrated by the Schlumpf mountain drive marketers. Sure torque is equal but the moment arms are less than half as long. Running the mountain drive with chainring smaller than 55 teeth will put loads on chain and cogs beyond a normal derailleur drive with 22t granny. The smallest cogs are at greatest risk.

The speed or high speed drive would be better solution, but the 27 tooth chainring is too large, especially on 29er.


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## unterhausen (Sep 28, 2008)

Front derailleurs don't shift well, but it's really hard to beat the chainring setup for efficiency. For as seldom as I shift in the front, I'm not going to carry around a batch of inefficient junk. Wake me up when they invent something that works as well as a single chainring. Is it really that hard to add a few gears in the IGH?


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## khachkar (Jan 19, 2010)

Not sure if this has been answered yet, but I just joined and wanted to find out if the Specialized Enduro has the ISCG tabs req'd for the Hammerschmidt?


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