Front hub motor/kit with roller brake

[Gabor]

This is my first post and i’d like to get some advise

We’ve just bought a Cortina U4 dutch transport bike for the wife.

It’s like this: https://www.fietsenwinkel.nl/media/catalog/product/cache/0/thumbnail/163b81649b7ef7bc8a00b0066e59ae0a/c/t/ct3ndd57bm_1.jpg

The bike came with front roller brake and rear coarser brake plus a shimano nexus 3 speed.

Cortina also makes the same bike with a front hub motor, but I simply could not justify paying 1800 euro for it. See here: https://www.fietsenwinkel.nl/media/catalog/product/cache/0/thumbnail/163b81649b7ef7bc8a00b0066e59ae0a/e/c/ecomo_grey_mat_1.png

It’s very much the same as the normal U4, but with 24V system, front hub motor, front roller brake and rack battery suitable for about 30km.

I’m thinking of converting the bike to electric and looking for options. I’d like to have the minimum parts replaced and definitely a kit with rack battery.

Daily commute for wife is about 15kms total, with some uphills. We don’t need very high speed but rather some torque for the way up to avoid sweaty morning meetings.

I was browsing Ciclotek and BMS Battery website and saw hub motors suitable for roller brakes on both. But not quite sure how reliable these smaller motors. Reason why I was looking these versions, because the bike fork has no option installing V-brake or others (as it came with dynamo hub and brake). As far as I know mid motor won’t be an option due to rear coarser brake.

What would you recommend?

thanks!

 

[flecc]

Gabor, I'm sorry to have to advise that the prospects for electrifying your new bike at a low cost are very slight.

A rear hub motor kit isn't suitable since it loses both your three speed hub gear and coaster brake, and the full chaincase is another complication.

Again the full chaincase makes a mid motor far less suitable since it would be difficult to combine the two.

That leaves a front hub motor, but I don't know of one separately available that has a built in roller brake, despite them specifying such a motor on their own e-bicycle. Since your forks have no provision for either rim or disc brakes, that leaves no easy fit options.

The best solution that I can see is to have a bicycle dealer change the forks for ones with disc brake fitments, since this would open up a wide range of front hub motor kits complete with a disc brake, some with the carrier mounted battery that you want.
.

 

[anotherkiwi]

What is that chain guard made from? Looks like a fabric of some kind?

If it is:
- Scrap it
- mount a BB kit
- add another chain guard that works with your BB motor

That rear rack is too fabulous to scrap so that you can put a battery rack there, put your battery in a pannier bag.

 

[anotherkiwi]

Just noticed the stand is that a problem for a BB motor?

 

[Gabor]

thanks!

yes the guard is some kind of vinyl.... wife would kill me if I touch it
indeed it has a dual side stand too, really needed because the bike is front heavy due to the font rack and we have a basket there too. can't realy get rid of the stand or replace to s single side as the bike would fall...

pannier bag is a real good option for the battery, thanks! I would have hated installing an aftermarket rack... i probably go for the bag in case I figure out the rest of the kit...

What is that chain guard made from? Looks like a fabric of some kind?

If it is:
- Scrap it
- mount a BB kit
- add another chain guard that works with your BB motor

That rear rack is too fabulous to scrap so that you can put a battery rack there, put your battery in a pannier bag.

 

[flecc]

These objections are why I recommended the forks change to a disc mounts one. That would keep the Dutch character of the bike intact, such things as the chaincase and stand.

Front disc brake motor kits can come with flat carrier style batteries which can be bag or box mounted on top of the existing carrier or in a side pannier.

As I'm sure you will know Gabor, front hub motors on pedelecs are very popular in The Netherlands for these reasons.
.

 

[Gabor]

...
As I'm sure you will know Gabor, front hub motors on pedelecs are very popular in The Netherlands for these reasons.
.

Yes, indeed, I found some ebike sites today, and Q85 seems to be the choice on them. However, as we know Netherlands is not very hilly, like 90% of the land is under sea level. So cruising with the Q85 might be fine.
My wife will be using the bike in Brussels and she needs to climb a little on the way to work.
Nevertheless, I might give the Q85 a try and order it from BMSBattery.
Question is that which sine wave controller shall I pick, maybe the S06S (if it's compatible?) or the recommended LSW-675.
And of course which battery? I guess even the less powerful is Ok for a 15km commute.

 

[anotherkiwi]

And of course which battery? I guess even the less powerful is Ok for a 15km commute.

Always choose more than you think you will need because she will be riding it farther than she thought she would

 

[DuncanDK]

You could also consider a front hub motor and see if you could install a front rimbrake behind the fork.

There is no room in front of the fork because of the front carrier. Mayby you could put the rim brake behind the front fork... the bolt is there...

(Or scrap the front carrier and mount a front rim brake in the regular place)

...Nice bike, by the way...

 

[flecc]

I agree with Duncan's suggestion of a rim brake behind the fork. A caliper brake would need no special fitments and that rear position is the most logical for the thrust to be being taken by the fork.

The very successful original Kalkhoff Agattu had it's front brake mounted that way.
.

 

[RobF]

The fitted lights are another complication, depending on how they are powered.

I know the bike has a front coaster brake, but I suspect it also has a front dynamo in the hub.

You will lose that with a front hub motor.

 

[Gabor]

Thanks for the good advises guys, really appreciate it!

It's about 20 years that I last serviced my teeneger bike, so completely forget about caliper brakes.
I'll definitely measure the space the front carrier gives me. I might need some spacers, but the brake could probably fit even in front of the fork. I think I would need some kind of fabricated mounting bracket in case the caliper brake would go behind the fork.

As far as the lights concerns, I dont see that a big problem. Indeed everything is powered by the front dynamo hub now, which if I upgrade to ebike, would need to be coming from the battery. I'll sort that out...

Thanks again for all the suggestions so far!