Go Back  Bike Forums > Bike Forums > Electric Bikes
Reload this Page >

Re: Power Efficient Ebike Conversion Help

Electric Bikes Here's a place to discuss ebikes, from home grown to high-tech.

Re: Power Efficient Ebike Conversion Help

Old 09-05-18, 09:54 PM
Junior Member
Thread Starter
Join Date: Oct 2014
Posts: 22

Bikes: Dahon Speed UNO, Schwinn Hybrid, MTB

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 5 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Re: Power Efficient Ebike Conversion Help


I purchased a 8 speed legend populo commuter bike. I like the look of it and I want to convert it to an ebike. I do not mind peddling and need some assistance with hills. So, I want something simple, small, and efficient. I am leaning towards a small front hub. Does anyone have any 250w front hub recommendations? My goal is to have something that is efficient that will give me a boost up hills.

1398567 is offline  
Old 09-06-18, 12:04 PM
Senior Member
slomoshun's Avatar
Join Date: Dec 2011
Location: 98059
Posts: 180

Bikes: Treks and a Moulton

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 62 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by 1398567 View Post
....Does anyone have any 250w front hub recommendations? My goal is to have something that is efficient that will give me a boost up hills.
A 250w hub is fine for level ground and mild inclines, but anemic on hills. A 350w geared hub is not much larger in diameter, but noticeably stronger. Like a 250, it can also be used on steel forks without a torque arm. I had bikes with both sizes and compared them on the same climb. Where the 250 need to be zig-zagged to maintain road speed and keep the motor from bogging, the 350 would go straight up.

You might find these threads interesting...
slomoshun is offline  
Old 09-06-18, 06:57 PM
nfmisso's Avatar
Join Date: Mar 2011
Location: San Jose, CA
Posts: 2,990

Bikes: 1980s and 1990s steel: CyclePro, Nishiki, Schwinn, SR, Trek........

Mentioned: 12 Post(s)
Tagged: 0 Thread(s)
Quoted: 381 Post(s)
Likes: 0
Liked 1 Time in 1 Post
I suggest that you take a look as something like one of these:

And then change the sprocket to only provide assist up to say 10 mph. The motor has a freewheel on it, so no problem over speeding the motor, or shutting it off entirely. The motor will provide no assist above its maximum revs. The above motors at the output of the gearbox run about 300 rpm at the rated voltage; they have a 12T sprocket. To get ~10 mph, that would be matched with a 30T sprocket on the rear wheel. This would give you a good amount of hill assist, and absolutely no top speed assist.

Motors do not like to be heavily loaded at less than about half their maximum speed. Hill assist is almost always by definition less than that. Many direct drive hub motors have a noticeable amount of drag when not powered.
nfmisso is offline  
Old 09-07-18, 01:18 AM
Senior Member
momsonherbike's Avatar
Join Date: Nov 2012
Location: Northern Virginia
Posts: 252

Bikes: 1995 Giant "Nutra" crosstrail, 2012 Giant "Avail 1" road bike

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 36 Post(s)
Likes: 0
Liked 21 Times in 14 Posts
Clean Republic has a nice 250w front hub that is extremely easy to install, small and unobtrusive if you want your bike to pass at first glance to look exactly like a "regular" bike, and will certainly help on the hills, but can't surmount anything other than a mild slope on its own. You will need to pedal. Finger tip throttle only. They also have a 350w kit with a variable thumb throttle. This size motor is more agressive when it comes to hills. The hub is bigger, however, and gives the donor bike more of an "ebike" look. I purchased my 250w kit with two 20 mile lithium batteries from them several years ago, and still love using it. It is my favorite bike to ride anywhere and everywhere, and no one has ever been able to discern that it is anything other than a simple vintage hybrid bike. The motor is so small that it just doesn't stand out.

They are a very reputable company with excellent customer service, and excellent products. US based, west coast.

Last edited by momsonherbike; 09-07-18 at 01:22 AM.
momsonherbike is offline  
Old 09-07-18, 01:05 PM
Senior Member
Doc_Wui's Avatar
Join Date: Jul 2015
Location: Chicago Suburbs
Posts: 778

Bikes: GT Transeo & a half dozen ebike conversions.

Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 183 Post(s)
Liked 3 Times in 3 Posts
I would rather have a 500W rear hub, but this might be enough with a 350W front. While I have never seen this kit in person, what I like about it is the prospect of an easy installation. The electric controller is inside the battery so Installing the battery cradle on the water bottle mounts is all you have to do. The 62 mile range is probably attainable at 12 mph. (I've done 67 miles on a similar sized battery and similar size motor.

Its main failing is no pedal assist, but one can ride on manual pedals and feather the throttle for help on hills. And I dunno how they are on customer service.

The other issue is that every bike conversion is different. Don't know if your front forks are conducive for a front motor.

Doc_Wui is offline  
Related Topics
Thread Starter
Last Post
Pacific Northwest
05-03-17 04:25 PM
01-01-11 10:19 PM
11-30-10 04:07 PM
Northern California
08-26-08 02:07 PM

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.