speedhub 100Nm limit



New Member
Nov 17, 2008
New Jersey
I think the speedhub would work really well for gearing, but I notice they specify a torque input limit of 100Nm. I'm a little unsure of how to figure out what this means in terms of engine power limit. According to my calculations, with a 20inch wheel, and max power at 15mph, hp limit is about 3.8. Am I correct? A little help here? I'm not sure how much hp the ht's make either, but this would mean the morini s6-t would be too powerful.

edit: actually I think I messed up with calculations my new hp limit is 13.6, is this correct lol?
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Motorized Bicycle Senior Technologist
Jul 7, 2008
are you referring to an internal gear hub? I have an 8-speed internal gear hub on a 26" wheel. I did'nt made any calculations like you did. I just installed and fire away... I don't think the HT engine can ruin the internal gear hub as long as the sprockets are geared properly.


New Member
Oct 4, 2008
In the wind
The Rohloff hub is a nice piece of work but you can buy 3 Nuvinci hubs for the same price as one speedhub. I also have a 20" rear wheel and searched around and got a complete sachs 3x7 hub/front wheel takeoff from a new bike on fleabay for $250. Talk about some gear range! The Shimano Nexus 8 is supposed to be reliable also. There are plenty of options out there, but the trick to internal hubs is in how you shift them. If you shift under too much load they will implode, just back off the gas a bit while shifting and you will be fine, even with an old 3 speed model.