Electric Bikes - Hub motors with disc breaks?
Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.
01-17-08, 03:32 PM
I'm narrowing down my options here for adding electric assist to my cargo bike. Right now the bike has 8" disc brakes front and rear. With the hills around here I would hate to go back to rim brakes on either end of the bike.
So far, I've found that Bion-X and Ezee have disc brake compatible hub motors. Are there any others out there?
01-17-08, 03:40 PM
Ebikes.ca has Crystalyte models with disk brakes as well.
I run an Xtracycle with rim brakes and they work just fine, exceptionally well even. The only consideration is rim heating.
01-17-08, 04:16 PM
I don't want to start a rim vs. disc brake debate. I love my big disc brakes and I'm keepin' 'em. :D
I also am fully aware that a part of my affinity for discs is a style thing.
Cool, thanks. I didn't see a direct reference to disc brakes on the ebikes.ca site before. Now that I go back and look, I see the parts listed to adapt discs to some of their hubs. This is good since they have a much bigger choice of options to satisfy my inner bike geek. I'll go have a gander at the Crystalyte site.
01-19-08, 01:51 AM
a Bionx Hub?
its the exact same thing i'm thinking of on my Xtra too.
01-19-08, 02:02 PM
One other comment i'd like to make is that BionX is similar in power to a Crystalyte 408, which is enough for an unladen cyclist, but most utility bikes would render it pretty weak. Unlike the Crystalyte series though, where you can upvolt or pick a higher wound motor, BionX leaves you stuck. My advice here would be to be sure you'll be happy with the torque output by trying one out.
You'll find that pound for pound, the Ezee will put out the most torque by far being a geared motor but it'll also make a bit of noise.
01-19-08, 05:30 PM
So, kind of thinking out loud here...
The Ezee front hub kit looks interesting. One good thing about it is that the components like the controller can be swapped out with others such as the Crystalyte. This would allow over-volting, different battery packs, etc. Since it is a front hub it would be much easier to take on and off the bike or even swap to another bike.
The BionX looks like a very nice setup but, as noted, the components are proprietary. Another thing I don't like is the freewheel. Range is very important for my intended use of this setup. Lack of being able to upgrade to a larger battery, combined with losing gear options may be a serious negative for my intended use. When you're hauling cargo up a hill and the battery dies, gear ratios and gear range make a difference.
I will be using this rig for commuting and for general purpose errands and transportation. I want to be able to ride more often, take longer trips, and be less sweaty when I get there. My commute is ~15 miles each way with a pretty decent hill at the work end and an even bigger hill at the home end, if I want to do useful things like stop for groceries on the way home - a major reason for looking at an assist motor.
I looked at the Crystalyte site and it appears that the only disc brake hubs are rear hubs. The more I look at this stuff, the more I don't like having to give up my existing modern, high-end drive train.
If I remain stubborn about discs and modern drive train components, am I left with the choice of the Ezee and waiting for news on the Stoke Monkey?
01-19-08, 06:06 PM
Well, freewheels mean less gears, but not necessarily poor gearing. Shimano used to make an 11-34, 7 speed freewheel "megarange", which i'm not sure they do anymore. Its still an easy task to find a 13-34 or a 14-34, both of which are more than adequate for utility bikes. The only trick to these setups is that the higher ranges are evenly spaced, but there's a big jump between first and second.
As to why these companies are still doing freewheel over cassette, I don't know. I could see Crystalyte doing something like that as their product really doesn't evolve much, but with how "cutting edge" BionX is, you'd think they'd have figured out a way to work cassette into the mix by now.
Its still possible to obtain a good gear range, just impossible to do one which is evenly spaced all the way.
I wouldn't honestly suggest BionX for a utility bike to begin with, it doesn't put out a lot of torque compared to some other systems, I would personally value added torque output over a few pounds of weight.
Ebikes.ca also had some experimental Crystalyte motors with cassette systems on them a while back which had some problems but which could be solved as well, Email them and see if they have any solutions in this regard.
Personally, the Ezee seems like a pretty good solution as long as you're planning on mounting it into a rigid fork. These kits put out quite a bit of torque, and you could keep both things you love.
Powered by vBulletin® Version 4.1.12 Copyright © 2013 vBulletin Solutions, Inc. All rights reserved.