SRAM IGH vs Derailleur

[HDMW]

Hello :
I understand SRAM has stopped making IGH and has launched 1X drive trains, a new product which appears to be merely another rear derailleur. A second chain ring may be an option.

Going in this direction seems bizarre to me. I've wanted to get rid of my derailleur for years.
Am I missing something here?

One answer to my last question pointed out, a T-Tris 20 (or perhaps any trike) with an IGH still requires a chain tensioner. Could the 1X SRAM product be merely giving in to the inevitable?

Regards : Hubert Wagner
France

 

[ferret]

1X drivetrains is a trend that has become popular in mountain bikes in the last few years. People want to eliminate the front derailleur to reduce complexity and weight. They are not intended for the same users as IGHs.

 

[HDMW]

Hello Ferret :
Thanks for your response.

But why not use IGH for mountain bikes as well? I would have thought the very last item one would wish to have on a bike that goes through the bush is a rear derailleur. (I don't do that myself). Just pushing my road bike 60 m through long grass to the road, the derailleur often pickes up blades of grass.

Regards : Hubert Wagner

 

[ferret]

Hubert,
Although they have the advantages you mentioned, IGHs didn't take off in the MTB world mainly because they are inferior to a derailleur system in these aspects:

Heavier.
More expansive.
In most case have a narrower gear range.
Incompatible with modern mountain bikes rear axle standards.

From an e-biking point of view, most can't take the torque of a powerful electric motor.

Avner.

 

[amberwolf]

It's not usually the torque itself, but the sudden shock loads. If you ramp the power up or use a "cush" shock-dampener on teh input sprocket, (or output sprocket of the drive motor), it'll minimize that shock.

Then just ensure the torque output of the motor doesn't exceed the torque input spec of the IGH (you can gear it to ensure this).