I added a Hammerschmidt All Mountain 2 speed bottom bracket/crankset to my Santa Cruz Nomad mountain bike in the spring. I’ve been holding off posting a review until I got more miles on the bike. Unfortunately my kiteboarding addiction has seriously cut into my dirt biking time this summer so I have’t racked up quite as many hours on the dirt as I would like, but I figure I’ll share my impressions so far and then post again later in the winter.
The photo above shows my Nomad with double chainring and long-cage SRAM X-9. I replaced the big ring with a bash guard since it was rarely used. I liked this setup except that I found on technical terrain I was shifting the front derailleur up and down a lot which was sometimes a challenge and rarely using the rear derailleur since I needed a big jump in gear range fast. This meant a lot of blown shifts and a lot of chain slap as all that slack bounced around in the small ring where I stayed a lot.
Click on the image above to jump to my post discussing the details of the Hammerschmidt and the pros/cons I anticipated before using the system.
I got the All Mountain version of the Hammerschmidt because it provides the equivalent of a 24T [direct drive] and 38T [over drive] chain ring setup. I chose the 170mm crank length to replace the 175mm SLX cranks on my bike because the Nomad sits very low to the ground and I thought shorter cranks would reduce the number of times I whack my pedals into rocks.
I want to thank Ken at Power in Motion for giving me a pro deal on the Hammerschmidt and wading through all the technical stuff so that we got in the right combination of parts.
I replaced the SRAM X-9 long-cage derailleur with the short-cage version since I didn’t need to take up nearly as much chain slack with a single front ring and to benefit from faster shifting and less chain slap.
You need to face the BB shell and the ISCG tabs when installing a Hammerschmidt so everything is aligned properly. Not tools I have at home so I decided to let Bow Cycle do the install. They did a great job installing the Hammerschmidt, X-0 shifter and X-9 derailleur.
If you are keen to do your own install you can get a LBS to face the BB shell and ISCG tabs for you then follow the instructions in the video above.
What do I think so far?:
- I love the instant front shifting
- you get a high and a low gear exactly when you want it
- you can shift when stopped
- you can shift when coasting
- you can shift when pedaling backwards
- you can shift when pedaling forwards
- as a result you are always in the gear you want
- HS shifts are fast and crisp
- rear shifts with the short-cage derailleur are also faster and more reliable
- nice chainline allows full use of rear cassette in high and low gear range
- you get less chain bounce when bombing downhill and the chain can’t come off the front ring
- no performance change in low range as it’s direct drive
- some noticeable drag in high range
- very loud angry bee noise when freewheeling or back pedaling in high range
- extra weight over stock setup not noticeable when riding
- tons of ground clearance for HS vs. a normal chain ring setup
- no suspension problems or pedal feedback from running in the small ring all the time
- no problems or adjustments req’d so far
Should you get a Hammerschmidt?
Leaving cost out of it I would recommend the Hammerschmidt to anyone who rides technical all mountain style offroad terrain as long as you are not bothered by the downsides noted below. As the trail goes up and down again and again you’ll love the ease with which you shift the HS from high to low and back. It performs well and solves a real problem in mountain biking. It seems robust and all reports I’ve read indicate its low maintenance.
Unfortunately the MSRP in Canada is ~$1000+install – yikes! Although I love it so far I can’t say that there is a $1000 improvement over the stock setup. I wouldn’t have given it a shot if I had paid full retail and even at pro-deal costs it was a big decision. If your bike is working fine just stick with what you have. If you need new cranks/front derailleur/shifter then it’s probably worth it if you can hunt around for a deal.
The best plan is to buy a new bike with a Hammerschmidt installed as an OEM component. You’ll get the HS for the lowest price point and the bike will be designed with the HS in mind. I think the HS works so well you’ll see more and more all mountain bikes designed for it.
Since the HS is so expensive and so unique I wanted to tackle some of the problems it has in detail so you can understand how they apply to you better:
- The HS weighs more than the parts it replaces. I haven’t noticed this when riding so it’s not a problem for me. If you really care about weight you probably have a spreadsheet with the weight of every component of your bike listed so you’ll be able to figure how much extra weight the HS adds. Chances are if you have such a spreadsheet it’s too much and if you don’t know how much your bike currently weighs it won’t bug you.
- ISCG tabs are needed to fit a HS. Some people have made the HS work without these tabs, but this requires more than your average DIY skills and may damage both your frame and your HS so be aware of this.
- There is noticeable drag in the HS high range 38T ring setting. I don’t find this a problem for my mountain biking since I’m typically in the 38T high range when going downhill and I don’t really care about 5-10% efficiency loss because I’m not really going full out and a lot of the time I coast downhill. If you think you’ll be in the 38T high range a lot and/or you race this will probably be an issue for you.
- The HS compresses your suspension as if it was in the small 24T ring all the time [which it is!]. Some suspension designs rely on different size chain rings to change the angle of the chain relative to the cassette to account for changes in weight distribution when climbing/descending. I haven’t noticed this, but I climb aggressively and descend more passively. So my Nomad is working optimally when I need it to and is not affected when I start going down. If you really attack the downhills and pedal hard going down you may notice a loss in suspension performance. Note that if you buy a bike designed for the HS this won’t be an issue.