TDCM IGH DD discussion

[thunderstorm80]

Hi,
One of the candidates for building an electric touring bike is the TDCM IGH direct drive motor.
It will be working together alone with a second front direct drive motor - H3525 or 9C+ 2707.
http://www.ebikes.ca/shop/ebike-parts/motors/igh-305.html

I have some questions and I would be happy if you can answer some of them:

1. They rate it as 500W-1000W, but my 9C+ 2706 is also rated for that range but it has a higher copper fill. Would you rate it as less powerful?
2. Does anyone have any experience with it, regarding gear shifting reliability and the motor in general?
3. What is the maximum and the minimum sprocket I can mount on it?
4. Can it be used in conjunction with a triple-crank and it's front-derailler? I ask because in regular rear-cassette you shift the gears not only for the ratio, but also to keep the chain on a strait line, which is a problem if you only have one sprocket - unless it's located in the "middle" of our replaced imaginary cassette?
5. The IGH hub weight alone is 2Kg which seems a lot to me, but I have no experience with IGH's. Is it the normal weight among these beasts? It seems I will gain around 1.4Kg just by replacing my derailler and the 8 speed cassette to this fellow, and lose some of the range ratio.
6. I was sniffing around ES, and discovered that the motor torque is transmitted through a single key on one of the axles. I couldn't understand better as there were no other pictures and explanations - but it seems like a highway to failure? Since the motor is the part that is laced to the wheel - if you lose that part, your pedaling effort will just like be in "neutral" gear, if I understood it correctly?
7. The rotor holes are of non-standard geometry. Is it easy to find a disc rotor for it?
8. With all my love to Grin, I heard there is also a slower wind version that they didn't choose to sell. Do you know where to buy it? Or maybe you have other knowledge of other DD's with IGH's you can recommend me? (ones with higher speed count than 5)

Thanks for any info
Roy

 

[spinningmagnets]

The 9C typically has a 28mm/30mm wide stator (depending on the manufacturer), and a stator lamination about 205mm diameter.

The TDCM magnets are 30mm wide, and the best "estimate" I can come up with for the stator is around 182mm diameter. Too bad they didn't go for 40mm wide, or 45mm wide. The integrated IGH means they don't need to squeeze-in a multi-speed freewheel...

 

[thunderstorm80]

Thanks for any info

https://endless-sphere.com/forums/viewtopic.php?f=30&t=63284

Thanks, but I was already reading that thread before opening this one, and it doesn't help much

 

[thunderstorm80]

Then why not ask your questions there, where people already discussing it might see them and answer, rather than start a whole new thread about the exact same subject, separating all the new information from the old, and where it's less likely that those with the information you're after (those in that thread, most likely) would see your question and be able to help?

I can merge this thread with that one if you'd like to keep all the information together, which would be better for future people looking for stuff about this motor-system.

Okey. Do that.
I opened a new thread, because from my experience - when threads get long, the discussion goes off topic, and then people don't pay attention to new posts in that old thread. But maybe I am wrong. Merge it and we will see. Thanks!

 

[thunderstorm80]

Then why not ask your questions there, where people already discussing it might see them and answer, rather than start a whole new thread about the exact same subject, separating all the new information from the old, and where it's less likely that those with the information you're after (those in that thread, most likely) would see your question and be able to help?

I can merge this thread with that one if you'd like to keep all the information together, which would be better for future people looking for stuff about this motor-system.

As you see, now that you merged it with an old post, there are no more replies. Maybe split it back up again?

 

[thunderstorm80]

Then why not ask your questions there, where people already discussing it might see them and answer, rather than start a whole new thread about the exact same subject, separating all the new information from the old, and where it's less likely that those with the information you're after (those in that thread, most likely) would see your question and be able to help?

I can merge this thread with that one if you'd like to keep all the information together, which would be better for future people looking for stuff about this motor-system.

Can you separate my question to a new thread again?
Just as I thought, my message has been swallowed inside that bigger thread, which already has non-relevant discussions, which prevents any useful help...
No one has answered me since you separated it.

 

[panurge]

Hello
I'm building up a bike with that motor, I'll post my reports on the original thread, where you find even my new build thread link. Hope this will help....