Schlumpf HSD

“If you’ve got it, flaunt it” so they say. In this case I am talking about having the money to afford some nice features on a tadpole trike. The Schlumpf HSD (high speed drive) is one such feature. In a word … NICE! They aren’t cheap monetarily speaking, but they sure are NICE! The cost is about $800. They come with a 5 year warranty. Here is a video about them …

Schlumpf is a company out of Switzerland that specializes in internal hubs. Their internal hubs are all located in the front however, and not in the back as is the traditional internal hub location. The beauty of this HSD is that it eliminates the standard front derailleur and improves the chainline besides just giving you higher gearing. Another big advantage is that you can shift at anytime, whether you are stopped or coasting, so you’ll never get stuck in too high of a gear. The low gear is the equivalent of a 27 tooth sprocket and the high gear is the equivalent of a 67.5 tooth sprocket. The standard large chain ring found on tadpole trikes is 52 tooth and the largest available chain ring is 56 teeth. So you can see the huge difference … 52 to 67.5.

A standard 9-speed cassette found on many trikes (11-32) in combination with the HSD provides a gear inch range of 17 to 123, compared to the stock gearing of 18 to 96. Most newer trikes are 10 speed and have a 34-tooth low sprocket. This equates to low-speed gearing of 16. With this kind of gear range a rider should be able to climb almost any hill, as well as be able to pedal at well over 30 mph. Now that is quite a range. I told you it was NICE! Install a 14 speed internal hub in the rear wheel and you can do some serious riding with the gear ratios available without having to deal with a derailleur system and all the inherent problems that come with them. That would really be NICE!

It takes special tools, knowledge and ability to install this unit so it is not something most of us could do ourselves. Even if we were “qualified” the special tools needed are extremely expensive so it would be quite impractical unless you would be installing these for a living. 🙂  Here is a video about installing the Schlumpf HSD …

Note: Utah Trikes states that they install the drive free if you buy it from them.

Here is a picture of the chamfering tool in use on a bicycle …

schlumpf chamfer

And here is what the finished chamfer looks like …

chamfer completed

As you can see once chamfered there is not much hope to ever going back to a standard crankset. A new boom would be needed to do so.

Here is a video of an ICE tadpole trike with what I would consider the ideal setup I have previously eluded to … internal hubs front and rear which are neat, clean, and nearly maintenance free …

Yeppur! The Schlumpf HSD is really NICE! Now if I could just get someone to buy me one. They are really nice, ya know! So if you’ve got it … you can flaunt it! One last thing … they are really NICE!

HERE is Utah Trike’s article on this product.

Author: Steve Newbauer

I have a few current blogs (tadpolerider1, navysight, truthtoponder and stevesmixedbag) so I am keeping busy. I hope you the reader will find these blogs interesting and enjoy your time here. Feel free to email me at tadpolerider2 at gmail dot com (


  1. Quite expensive but it seems to be the only model in the market with such a radical overdrive. Large and weaker rear wheels are no longer needed to get some serious speed. With a Schlumpf HSD even a weaker person can get high speed on flat stretches and downhill, leading to significantly higher average speed without too much effort.

    No need for costly special tools, wich can be rented if you need any of them.
    This and picture can be found on the FAQ Schlumpf E3.5.2
    “There is a torque lever available for high-speed-drive, in case the standard cone rings don´t work or there is no bottom bracket shell to be used for holding the reaction torque.”
    In other words: If you can live with this extra torque lever on your trike, there will be no damage to the boom or bottom bracket shell and the use of it also simplifies tightening. No cone-rings/ chamfering and you can do the job your self.
    The torque lever fits very well on a trike boom.

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