Are there any good free running motors that support disk brakes?

[Pedalo]

Hi,

I've decided my next bike must have disk brakes given the rate I'm getting through brake blocks and wheel rims. It also will have to be a retrofit because I'm restricted on where I can buy the bike under my company's cycle to work scheme. The motor can be front or rear hub.

My only experience so far with electric bikes has been with Tongxin motors, first on a Cytronex and now on my DIY electric Brompton.

I'd like the new bike to ride as easily as possible without having to switch the motor on. I ideally only want to use the motor to provide a little assistance up the steepest hills and for this I currently only need a small battery to for my every day commute.

What's the best option for a DIY/ retrofit build that best matches my requirements? Will I be disappointed with anything I get having got used to the free running Tongxin? Are there any motors thay support disk brakes that get close?

 

[piotrmacheta]

I only have experience of the eZee kit and I use it unpowered and it feels free running. The only thing I notice is the weight of it when I turn quickly when going off-road but other than that it's great. And it's powerful enough for steep hills too.
I have a rear kit on my recumbent and a front hub on my mountain bike and they both take a disc brake (180mm only).

 

[Pedalo]

I only have experience of the eZee kit and I use it unpowered and it feels free running. The only thing I notice is the weight of it when I turn quickly when going off-road but other than that it's great. And it's powerful enough for steep hills too.
I have a rear kit on my recumbent and a front hub on my mountain bike and they both take a disc brake (180mm only).

Thanks for the reply. I think most of the bikes I've looked at have 160mm disc rotors. Is there likely to be a problem with that?

Do you know if it's possible to buy the Ezee kit without a battery? I already have batteries and chargers that I would like to reuse.

 

[jayuk]

On my mtb the front disc 180mm & rear is 160mm.
If that help?

Jay

 

[Packer]

You can get Tongxin hubs with fittings for a rollerbrake, and you can get rollerbrake to disc brake adapters, so in theory you should be able to use them together. I can't see why not, although I have yet to see anyone who has done it. I am planning to try it myself later this year.

Rollerbrake to disc brake adapter:
Cesur - Fahrradmanufaktur Münster - Ihr Fahrrad nach Maß - Custom Made Bikes - Cesur Scheibenbremsadapter Disc-Adapter

BTW, most mountain bikes have 160mm discs front and rear. Although there are a variety of sizes from 140mm up to 230mm I believe.

 

[banbury frank]

disk bike

Raleigh are launching a New version of there Peak Bike available on the

19 th Feb

180 mm hydraulic disc brakes front and rear about £495

To buy a motor and controller disk brake compatible the Nine continents motor is available from www.ebikes.ca Homepage of the revolution delivered by FedEx 4 days

with there controllers you can plug in the cycle analyst

Full control of the bike


You will have to pay vat when the motor is delivered

Excellent service on line shop and you can pay by paypal

Frank

 

[Deleted member 4366]

What's wrong with a Bafang
products-Suzhou Bafang Electric Motor Science-Technology Co.,Ltd
They do front and rear with disc brake and they're very easilly obtainable from a number of sources I have managed to fit one to a 160mm disc, but I had to grind some material off the caliper adaptor plate. 180mm is not expensive and you only need an additional caliper spacer, which is also cheap - about £14 for the disk + adaptor. I have found these Bafang motors are extremely free running when unpowered. That means un-noticeable resistance compared with my non-electric bike, but I'm heavy: Maybe if you're a 7 stone weakling, you might notice something - but I doubt it.

 

[banbury frank]

The Nine continents motor will run on 36 volt up to 72 volts

there controllers run as standard 36 or 48 volts and with a resistor change 60 or 72 volts the more power and speed you want change the battery voltage

so the motor and controller is for life

Frank

 

[Cyclezee]

Thanks for the reply. I think most of the bikes I've looked at have 160mm disc rotors. Is there likely to be a problem with that?

Do you know if it's possible to buy the Ezee kit without a battery? I already have batteries and chargers that I would like to reuse.

Hi Pedalo,

Yes, you can buy an Ezee kit with or without battery and there are several options to choose from as can be seen here http://www.ezeebike.com/eZee Conversion KIT.pdf

My kit came with a 180mm disc, but you could ask for a 160mm one.

Onbike should be able to supply everything you need.

J hn

 

[jbond]

What's wrong with a Bafang

What he said. They will work with a 160mm disk depending entirely on the caliper design. It all depends on the size of the inner face of the caliper. It's also likely to be easier on the really tiny Bafang QWSX/H motors.

There is *some* drag on these motors when freewheeling compared with a normal hub but not a lot. I suspect that the only way to eliminate this is some kind of mid mount motor with an extra freewheel. But that's almost impossible to arrange on a conventional bike.

 

[Tex]

on that what's happened to daahub?

 

[Pedalo]

Thanks all for the comments so far. I was initially going to get a Bafang but then started reading conflicting views on whether they are free running or not so wanted to check what else is out there. I guess Bionx is also a contender given it's now easier to buy in the UK. I don't particularly like the style of battery, and as as mentioned before would prefer to use my own battery, but it does seem to get such positive reviews from everyone who's owned it so it's worth considering.

Is there anything to watch with rear mounting hub motors in general? What's the compatibility like with cassettes?

 

[Deleted member 4366]

All 250w Bafang motors that I've tried have been totally free running. Try one - you won't be disappointed! When comparing motors, you have to make sure that all other factors in the bike are equal - especially the tyres. If you tried a Bafang with slicks and then a Panasonic with knobblies, you could very easily condemn the Panasonic as non-free-running, so I wouldn't believe everything that you read. We've had this debate many times before, so just try one for yourself (with slicks). I've heard of one guy whose clutch got stuck. He eventually got it fixed under warranty after a long struggle with a dealer that didn't have a clue about it. Naturally that one was difficult to pedall until it was fixed.

 

[wurly]

I have a Bafang front hub fitted to my wife's bike. It used to have a Tongxin hub which are renown for their freewheeling abilities. I swapped it out for a Bafang after the tongxin motor shaft broke up, i think in November 2010.
The Bafang is nicely 'run in' now and freewheels as good as the Tongxin hub used to. I reckon it has around 250miles on it
Look at the video
YouTube - SDC12193

 

[Deleted member 4366]

Here's our one that has done about 800 miles, which as you can see is significantly better. About 1 minute and 20 seconds from 20mph.
YouTube - Bafang

 

[wurly]

That is very good. Not sure what tyre you have there but it may have a bit more mass. My video shows a rundown from 15mph not 20mph.
I am expecting the hub to get better with age.
I think the point here is, there is hardly any significant drag at around 15mph and i expect you don't see any at 20mph either.

 

[Deleted member 4366]

When we first tried it, the brake block was just touching. Not enough to notice while riding, but the wheel stopped in about 20 secs. We adjusted the break and then repeated the test and it ran four times as long. This gives some idea of the insignificance of the motor drag!

 

[NRG]

Now compare it against a normal wheel with well adjusted bearings 1 min 20 run down from 20mph is very poor in comparison.

 

[Deleted member 4366]

Now compare it against a normal wheel with well adjusted bearings 1 min 20 run down from 20mph is very poor in comparison.

Yes, you're quite right, but twice an insignificant amount is still an insignificant amount!

 

[NRG]

But that's the point, its not insignificant. The difference is noticeable on the road, if you don't do the comparison you would think the motor added nothing but is does.... The effect is more noticeable the faster you go and also is more noticeable in colder conditions. I've compared directly on my Peugeot and also my Alien GSII with the Alien improving the most. No way are these motors totally freerunning.