Anyone using one of these and any bad points at all? Also how hard are they to fit? Cheers.

Don’t see many, guess they weren’t as good as promised.

You need ISCG mounts on the frame,that preferably have been faced or faff about with tiny spacers to get them even.Not difficult,just a faff.

Thanks guys my frame is a 2010 yeti dj that I want to fit front gears on for trail use so it has iscg mounts but I keep reading everywhere about the bb facing and such and wondered if it was crucial or just able to get around it.

Look at the Schlumpf Mountain Drive or Speed Drive – the Hammerschmidt has various problems that have never impressed me.

It was great at first but it lasted less than a year; the seals were poor and let done the design with (expensive) wear inside. Sram were no help even tho manul gave no service info..Heavy too.
Got carbon 2×10 now, which works great.

Thanks for the advice guys.

I had one on my old frame. You do need to either face off the mounting tabs properly or shim them. Its not that hard to do, just make sure you do it.

The system works well and does what it should do. It is heavier, but not enough to notice when riding. If you want a plummet and winch bike, or are going to ride round the Alps or tough trails on it then its great.

I liked mine, I only took it off to 1×10 because I wanted to up my fitness and 1×10 forced me into it.

Bad points are that it will need cleaing out if you ride in wet muddy conditions. Cleaing it is easy, just takes time and the tool. So if your not going to use it all winter then your fine. If you do want to use it in the sloppy crappy british winter (spring & autum) then you will need to take it apart and clean it.

I still have mine and the service tool, if you want Im happy to sell them to you. Im sticking with 1×10 now.

I quite fancied on of these to match up with my alfine as an all weather solution but if they often need cleaning it’s not so appealing any more

Thread from a year ago where I wrote my thoughts about my Hammerschmidt (LINKY).

I have managed to completely clag the thing solid with mud on a ride this year which was a PITA. I might try a mud claw thing if we don’t get a summer again.

I still like it; but I’m not sure it sounds good for what your after… if your going to be in the overdrive most of the time you will hate the feeling of the drag.

A Mountain Drive is direct ratio in the upper gear, so if you’re in the upper ratio most of the time there’s no drag. Though because of the needle roller bearings, there’s very little in the lower ratio either. A Speed Drive would give you a smaller chainring.

Neither setup needs special tabs on the frame, special chain rings, or cleaning out when it gets muddy.