TSDZ2 or rear hub motor for my recumbent trike?

[Simon Knight]

Hi, I have an ebike fitted with a 36volt geared hub motor (mahle X35) which I like because of its light weight and that the bike rides well unpowered.

Now I am looking to fit a motor to my recumbent trike. The trike has 20 inch wheels and so far I have not found a UK supplier of a hub motor designed for 20 inch wheels.

I have contacted Whoosh and been offered the TSDZ2 which they have in stock. I have no experience of this motor so have had to resort to google and this throws up reports that range from "utter rubbish failed within ten miles" to "wonderful - best motor ever". I suspect that the truth lies somewhere in the middle. One point I am unclear of is how well it rides power off and/or above the 15.5mph cut off limit.

So please let me know of your experiences with the TSDZ2 and also of any light weight rear hub motors that will work in a 20 inch rim.

best wishes
Simon

 

[matthewslack]

Hi, I have an ebike fitted with a 36volt geared hub motor (mahle X35) which I like because of its light weight and that the bike rides well unpowered.

Now I am looking to fit a motor to my recumbent trike. The trike has 20 inch wheels and so far I have not found a UK supplier of a hub motor designed for 20 inch wheels.

I have contacted Whoosh and been offered the TSDZ2 which they have in stock. I have no experience of this motor so have had to resort to google and this throws up reports that range from "utter rubbish failed within ten miles" to "wonderful - best motor ever". I suspect that the truth lies somewhere in the middle. One point I am unclear of is how well it rides power off and/or above the 15.5mph cut off limit.

So please let me know of your experiences with the TSDZ2 and also of any light weight rear hub motors that will work in a 20 inch rim.

best wishes
Simon

Search on here for TSDZ2 in titles for recent threads talking about it.

With a recumbent' s potential for high speed, you need to think about resistance to pedalling above 25km/h, as you may spend a fair amount of time there.

 

[saneagle]

Did Woosh explain how to get high enough gearing for your 20" wheels? I was thinking about fitting one to a folding bike but I'm worried that it might be a bit too slow or I have to pedal too fast. I'm more of a grinder than a spinner.

 

[matthewslack]

There's no easy obvious answer to this one. You might need to try more than one solution to find what works for you.

I think you will find too much resistance above 25km/h with TSDZ2 or Bafang mid drives, and possibly not as much uphill assistance as you want with a rear hub motor.

I find that an upright stance on a normal touring bike, aerodynamic drag naturally limits my cruising speed to around the 25km/h or a bit below, so except downhill or with a big tailwind, I rarely exceed that limit, and the drag from the motor does not matter.

But a recumbent has such better aerodynamics that it might feel really slow compared to non-electric because of the motor drag. Really, the speed pedelec class is a much better set of parameters for an electric recumbent: higher assistance speed and more power. But not so easy in the UK.

And a 250W hub motor will either be less than you want uphill, or if a slow wound, or a normal wind in your 20" wheel, will be better on hills but have a less than 25km/h maximum assistance speed.

Grin in Canada have made controllers that feed the motor just enough power to overcome the motor drag above the cut-off speed, for a different purpose. They wanted a non-free wheeling geared hub motor to allow regenerative braking. That technique applied to a mid drive motor might solve the conundrum, but it is not an off the shelf low cost answer.

 

[Woosh]

Did Woosh explain how to get high enough gearing for your 20" wheels? I was thinking about fitting one to a folding bike but I'm worried that it might be a bit too slow or I have to pedal too fast. I'm more of a grinder than a spinner.

How many teeth do you have on your biggest chainring?
The TSDZ2 is easy to fit and supplied with 42T ring 5-point BCD 110mm.
It's easy and cheap to change the 42T ring for something else to suit your pedalling.

 

[Bikes4two]

Hi Simon,
My friend has a Recumbent Trike to which he fitted a TSDZ2 to (250w 36v version) and I've not had negative reports from him about his ride experience.

He is not a member of this forum but I'll copy him in on the post and I'm sure he could answer any questions you might have and I'll foward his views.

As regards the TSDZ2 reliability, this like any kit motor, is a mass produced item where quality control is not what you'd find on a space rocket, so I'm sure some have had QC issues. What I can tell you is that I've installed 4 of these motors for myself and friends and my trike friend is the 5th motor owner I know, and we are so far, trouble free.

When you read of people's woes with the motor, it is difficult to get an understanding of how/what they were using the motor for. So someone weighing in at 120Kg duing bunny hops and other MTB stunts at full power on mountain trails in 30degC temperatures, may have problems not experienced by the 90Kg rider doing country lanes at lower power assist levels.

When I bought my motor I accepted that problems could arise but with the ready availability of spare parts and the combined knowledge on this forum and the wider internet (esp Youtube), I was happy at the price to give it a go - so far it has all gone swimmingly.

 

[Simon Knight]

Hi all,

Thanks for your replies which have been helpful. While a recumbent is more aerodynamic I only really notice an advantage when going down hill. I think I have hit fifty mph on the odd occasion, I say think because the vibration was so bad that I could not see my speedo. My more normal flat road speed is probably 13-14 m.p.h on the trike and 11-12 m.p.h. on an upright so I'm no speed demon. I'm hoping that a motor will help on the hills and accelerating a loaded trike on the flat.

The other weekend I visited the ICE stand at the York show where I tried various machines including one fitted with the Shimano Steps system and was surprised to hit speeds of 20 m.p.h. on the flat. I was interested to learn that most of the people from ICE ride electric trikes because they are so much fun. Mind you Cornwall has some killer hills whereas I live in North Lincolnshire which is pretty much flat as a pancake.

My trike is similar to the one in the picture above and is fitted with a triple on the front the largest ring is 52 teeth but I spend most of the time riding on the middle 42 tooth ring.

Based on your posts I'm warming towards the TSDZ2.

best wishes
Simon

 

[Nealh]

One can fit a double ring set up on the tsdz2 , if needed.