Do I need Rear Torque Arms

[Charliefox]

My Bafung 36V 350W Cassette rear hub motor having arrived ok, I am getting ready to install once a new tyre arrives.I was put off front hub by pics of broken alloy fork dropouts.What is the situation with rear alloy ones? The motor is 1:5 geared.I always pedal assist except downhill.

 

[trex]

yes, you should. You can make some like this one on the woosh zephyr-B:

 

[Deleted member 4366]

It won't break your frame, but, if it spins, it twists the wire until it brakes. You then have a difficult repair. To be safe, it would be best to use a torque arm on the brake side tied to the disc mount if you have one. You can get a torque arm from Ebay or Cyclezee. Make sure it has a 10 x 12 slot, not 10 x 14. £8.50

 

[baldylox]

You just have to ensure you get a longer m6 hex bolt to fit the torque arm to the brake calliper mount. I used the cyclezee one as d8veh suggests, works a treat and doesn't look too clunky.

 

[flecc]

If you have a fair size dropout plate on your frame you'll be able to use just the base bit of the eZee torque arm as I did on my bike by tapping a thread into it:

 

[Cyclezee]

Cyclezee torque arms are here on eBay http://www.ebay.co.uk/itm/261733254617?var=&ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649
They are very popular right now, 7 sets going to Tenerife today.

 

[Charliefox]

If you have a fair size dropout plate on your frame you'll be able to use just the base bit of the eZee torque arm as I did on my bike by tapping a thread into it:

View attachment 10589

Is this an alloy frame in the pic? My Giant FX3's have a lovely flat plate..so flat I am wondering if it is steel. I don't mind drilling and tapping steel but not sure about Alloy. Would a smallish bolt really be secure enough? Probably not relevant now as I ordered 2 Torq sets from Panda bikes on Ebay as I would like to connect to the lower disc caliper securing bolt on one side and maybe the gear hanger on the other. The bike I would really like to energise is my Trance X5 which has a very profiled dropout which means I will have to go SE to get around to NE and the caliper bolt!

 

[flecc]

Yes, it is an alloy frame and that fixing with a 6mm bolt has given no trouble with a high powered hub motor.
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[Charliefox]

Yes, it is an alloy frame and that fixing with a 6mm bolt has given no trouble with a high powered hub motor.
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Thanks Flec for that. err how high powered is your motor exactly? Reading possible but not likely prosecutions for riding with bigger than 250W motor, I was perturbed by the the bold CST 36V 350W 26 label on the Bafang motor just arrived from China. Perhaps I should dirty it up a bit! Seriously though, the 350W is only $2 more than the 250W, identical size and weight and just uses a 9 instead of 6FET controller. On rough or soft trails I doubt if it will go faster than my 250W on the tarmac.Just provided it doesn't overheat the C13/14 connection to the battery. I saw the Forum subject 'suspension' just now. Funny how they are all pretty old posts. Suspension has come a long way from 2007-8! My giant trance has air suspension back and front which can be hardened for the extra weight of motor and battery.The old drove roads and other trails in the Cairngorms are fantastic but ROUGH!

 

[flecc]

It's a Bafang with 30 amp controller, peaking at about 1000 watts gross. Only used on tarmac roads though, but in hilly territory.

Yes, like so much on e-bikes, suspension has indeed improved considerably over recent years in the best cases, but there are still lazy old style designs on some e-bikes.
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