Not a kit question per se, but does anyone here have knowledge or experience of making (or having built) a custom boom to take a Bosch (or other non BB fitting) mid drive? I think it's feasible, but the weight of the drive (I don't know what it is) may be a problem.
Recumbant trike query
- Thread starter grazie
- Start date
D
Deleted member 4366
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This one appears to come with the frame, so you only need to weld on a tube:
https://www.aliexpress.com/item/free-shipping-MM-G330-250-36V-250W-MAX-8fun-bafang-Gear-mid-drive-motor-kits-for/32727133648.html
Edit: I think they sell the bracket as an optional extra.
https://www.aliexpress.com/item/free-shipping-MM-G330-250-36V-250W-MAX-8fun-bafang-Gear-mid-drive-motor-kits-for/32727133648.html
Edit: I think they sell the bracket as an optional extra.
Thanks for the reply, but I may already have sourced a motor, etc . Also, it says that it's no longer available and woud have been pretty costly by the time it landed in the UK,
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You need someone who can weld up a special boom end. I was in contact with http://www.cnebikes.com about the http://www.bafang-e.com/en/components/component/motor/mm-g5101000.html because it is PAS only and can handle 48v. I was quoted $450 with the bracket.
The mounting bracket will need to be compatible with the boom material to weld correctly. I was thinking of shipping it to my trike manufacturer and having them make the boom I would guess for about another 350€
Right now I am keen on the idea of an all wood velomobile in which case I would have tabs welded to the mounting bracket locally so that I could bolt it into the frame.
This project is an if and when one depending on many factors beyond my control involving free cash
The mounting bracket will need to be compatible with the boom material to weld correctly. I was thinking of shipping it to my trike manufacturer and having them make the boom I would guess for about another 350€
Right now I am keen on the idea of an all wood velomobile in which case I would have tabs welded to the mounting bracket locally so that I could bolt it into the frame.
This project is an if and when one depending on many factors beyond my control involving free cash
D
Deleted member 4366
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I'll get the motor plus all that's needed to make it work (obviously not from Bosch). Is there some licencing issue of which I'm not aware, so that the complete drive system can only be used on the bike it was installed on?
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Sounds like a great project and thanks for the info. However, I'm puzzled that you got a quote from a Canadian company when you're in the EU. Were they the only people you could find?This project is an if and when one depending on many factors beyond my control involving free cash
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I think a Bosch torque sensor motor on a trike is a bad idea which is why I would choose a PAS only version of the bafang which has a cadence about equivalent to my natural cadence. Also why I will be using a GSM with external controller on my trike so that I have "complete" control over cadence, power and top speed.
Ah, I must have slipped up and looked at dealer addresses.
That's useful info, thanks. I'm still learning.
What controllers are you considering? A UK dealer that stocks both GSM and Bafang believe the Bafang kit is worth the extra £150 (I'm getting there...slowly).
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Deleted member 4366
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Does the Bosch kit have the correct wheel size? The Bosch system is programmed to exact gearing. It might work with different gearing, but not in an optimum way.
Most probably the 48v 20 A KT sine wave controller from pswpower. The battery will probably be a 12S 44.4v as that seems to be almost perfect cadence wise, I will try at 48v before commiting however.
Pretty poor design if the Bosch system isn't software configurable, at least to some extent. The wheel would have been the correct size, but after anotherwiki's comment on the Bosch torque sensor, they've been ruled out. GSM mid drive is now top of my list, although that may change again.
From Woosh, I already have it on my pedelec. I am running it at 44.4v at the moment (49.8v hot off the charger) with a 36v controller which is having some heat issues. When (if...) I sort my financial problems I will upgrade the controller and move the motor to the trike. Just about every 36v motor on the market can handle 48v just fine, it is the number of Amps you have to watch.
48v (54.6v hot off the charger) x 20 Amps = 960 W at the controller and about 760 W at the rear wheel. This is about 75% more than running the same motor at 36v x 15 A. Nasty things can happen when you get up to around 1.5 kW with a 250 W rated motor, you are better off with a 500 W or a 750 W motor if you want to go that far.
48v (54.6v hot off the charger) x 20 Amps = 960 W at the controller and about 760 W at the rear wheel. This is about 75% more than running the same motor at 36v x 15 A. Nasty things can happen when you get up to around 1.5 kW with a 250 W rated motor, you are better off with a 500 W or a 750 W motor if you want to go that far.
OK, great. I asked Woosh about how high a voltage I could put on the GSM motor and they said no more than 36V, but agreed many/most(?) hub motors can handle higher without problems. I suppose that means that if you use a higher supply, you're going to put yourself outside their terms & conditions. No plans to use higher than 36V initially to keep costs down, but I wanted to future proof the installation as much as possible.
Given the speed with which technology changes in some sectors, electric motors and batteries have been much slower to advance, so it as appears me.
Given the speed with which technology changes in some sectors, electric motors and batteries have been much slower to advance, so it as appears me.
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Is there a possible/recommended way to test the drive system before installing it on a bike?
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