Kit recommendation for hilly commute

General Discussion about electric bicycles.
Post Reply
SurlyFRS   1 µW

1 µW
Posts: 3
Joined: Sep 06 2017 5:12am
Location: NM, USA

Kit recommendation for hilly commute

Post by SurlyFRS » Sep 06 2017 5:32am

Hello! I'm looking for an ebike setup that will augment my pedaling effort on hills to allow me to get to work without getting too sweaty. Ideally, I would be able to pedal the bike without or with limited assistance, so I was thinking a geared hub motor would be most appropriate and budget conscious. I am an engineer with DC electronics experience, so I am not afraid of wiring up my own kit to save some $$.

Desired max speed on level ground: 20-30 MPH
Desired max range at what cruising speed: 22 mi at 20 MPH
Preferred bike wheel size, or wheel size of bike you want to convert: I have a Surly Crosscheck 700C I'd like to convert
Brake type of motor wheel. Caliper brakes
Rider weight. 185 lb
Terrain. Hilly, not sure of percents.
Budget: <$1k


Thanks!

User avatar
dogman dan   100 GW

100 GW
Posts: 34981
Joined: May 17 2008 12:53pm
Location: Las Cruces New Mexico USA

Re: Kit recommendation for hilly commute

Post by dogman dan » Sep 06 2017 6:34am

Because of needing a bit larger battery, and the cost of a good one, you might find yourself spending closer to $1500.

A typical "1000 watt" rear geared motor kit should do you just fine, with a 48v 15 amp hour battery. Generally you will get less than the 30 mph you'd like, but you will have 25 mph cruise easy. No problem on the hills, even if you wanted to ride from santa fe to the ski area.

The battery that size will have about 650-700 usable watt hours in it, and fast cruise will take about 35 watt hours per mile max. So 18 miles range with full throttle riding. Much more slower though. 25-30 miles quite possible with more pedaling lowering the wh/mi to more like 20-25.

You will be able to ride up some pretty steep hills at up to 15 mph, 5-8%. and get up way steeper hills that are short. On the downhill, the geared motor will coast well, extending the distance you go with the motor off. If its rolling hills, you can get back almost what it cost you to go up it, by coasting down. This results in very similar range to if you rode on flat ground at 20 mph.

You could shave the budget by choosing a very cheap direct drive 1000w kit, and get pretty similar results. But a geared motor will be more efficient in any stop and go, city riding, and go farther on the battery. On the open road, little difference in efficiency.

SurlyFRS   1 µW

1 µW
Posts: 3
Joined: Sep 06 2017 5:12am
Location: NM, USA

Re: Kit recommendation for hilly commute

Post by SurlyFRS » Sep 06 2017 8:58am

DD, thanks for the reply. I was hoping for front drive to keep my rear cassette, etc. intact; is that not a good option at this power level?

Was looking at this kit: https://bmsbattery.com/ebike-kit/346-ba ... results=37
And this battery: https://bmsbattery.com/ebike-battery/81 ... ttery.html

...which would come to $616 shipped. But only 500W. If I was happy with 10 MPH up hills and ~20 MPH cruise, would this do OK?

Of course by cheaping out now, I run the risk of feeling the need for speed later on and having to re-buy...

For reference, Google says my commute is ~750 ft up and 820 ft down on the way to work. the 750 ft is 2 fairly gradual hills ~1-2 miles long. If i have to sweat more on the way home I'm OK with that.

What should I be looking for in terms of motor RPM?

augidog   10 W

10 W
Posts: 84
Joined: Sep 29 2012 11:49am

Re: Kit recommendation for hilly commute

Post by augidog » Sep 06 2017 10:41am

....
Last edited by augidog on Jan 08 2018 3:34am, edited 1 time in total.

melodious   100 kW

100 kW
Posts: 1154
Joined: Aug 26 2011 8:57am
Location: East Coast, U.S.A.

Re: Kit recommendation for hilly commute

Post by melodious » Sep 06 2017 11:40am

The problem with the more powerful mid drives is it's ability to quickly wear down your drivetrain if used for speed. Granted, one can just carry an extra chain with you. May as well carry a chain break tool too for the inevitable miss shift. I even had to replace the derailleur due to chain suck :lol: . I believe if powerful mid drives are here to stay, then the bicycle industry should provide the necessary drivetrain components to survive. New chains (belts :idea: ) and gears that aren't putty.

For a commuter, I'd go a hub drive. Geared hub are usually well suited for hilly roads unless you want to dump amps into a direct drive using an upgraded 40amp controller. Direct drives have a better future upgrade path if you decide you want greater than 30mph speeds.
Last edited by melodious on Sep 06 2017 11:54am, edited 1 time in total.
Surly Ogre rigid 29er, rear 10T MAC @ 50V 25AH & 40A: 30mph road/gravel/hill machine
42" dual diagonal Eskateboard @6s & 90mm wheels
Next: eMTB @10-12s & 8"-12" pneumatic wheels; Got Strapped? d-(',')z

augidog   10 W

10 W
Posts: 84
Joined: Sep 29 2012 11:49am

Re: Kit recommendation for hilly commute

Post by augidog » Sep 06 2017 11:49am

....
Last edited by augidog on Jan 08 2018 3:34am, edited 1 time in total.

User avatar
Ykick   100 GW

100 GW
Posts: 5558
Joined: Nov 26 2009 6:10pm
Location: San Diego, California

Re: Kit recommendation for hilly commute

Post by Ykick » Sep 06 2017 12:03pm

BBSHD is the tool for this job, IMO.

I see "measurable" chain wear/stretch around 1000 miles. New chain ($12 8spd) at 1st sign of wear to save the more expensive sprockets. Yes, carry a chain breaker and couple master links in case of chain suck and it damages the chain plates and breaks. Very rare if everything is kept in good shape and adjustment.

TBH, I was concerned chains/derailleurs would be a major headache but they haven't. So much easier to fix flats, enjoy strong wheels, better weight distribution and of course the ability climb very steep hills. I'm talking stuff you can struggle walking up...
Talent must not be wasted.... Those who have talent must hug it, embrace it, nurture it and share it lest it be taken away from you as fast as it was loaned to you.

- Frank Sinatra

User avatar
wturber   1 MW

1 MW
Posts: 1999
Joined: Aug 23 2017 8:52pm
Location: Fountain Hills,AZ
Contact:

Re: Kit recommendation for hilly commute

Post by wturber » Sep 06 2017 1:51pm

SurlyFRS wrote:DD, thanks for the reply. I was hoping for front drive to keep my rear cassette, etc. intact; is that not a good option at this power level?
My super-limited experience is that once you have the motor, having all ( or even many) of your low gears isn't that important. I suspect that long term I'll probably use two or maybe three gears when commuting. I doubt I'll ever use the smaller front chainrings again. I intend to increase the front chainring to 50-52 teeth from the 42 tooth that came with this mountain bike. I may trade out the thumb shifter for an old-school friction shifter and get rid of the front derailleur. I don't need no stinkin' index shifting. :^)

I live in a hilly area and just put my first bike together, 1000W ebay (CNEBikes.CO) non-geared 48v rear drive with 7 speed cassette. I did very little shifting on this hilly test run. Here's some tracking of that test ride. You can drag the cursor over the graph and get speeds up hills etc. Note the downhill speeds even with the cogging of the gearless hub motor slowing things. Some of the hills are 10% grade or a tad more. My typical uphill speeds jibe with what the fellow recommending the geared rear hub said.

http://www.sportstracklive.com/track/de ... st/2346622

I plan on doing more test rides this weekend prior to commencing using the bike for commuting 15-16 miles up an down some hills.
"Commuter - DC Booster"
Iron Horse 3.0 hardtail - 48V / 1000W / 470rpm generic Chinese DD Hub motor (ebay)
8 x 36v 4.3ah 10s 2P battery packs - 1500W 30A DC Boost Converter delivers 54v and about 1000 watts peak
53T/42T Sakae Road cranks - 30mph+ on flats
viewtopic.php?f=2&t=90369

SurlyFRS   1 µW

1 µW
Posts: 3
Joined: Sep 06 2017 5:12am
Location: NM, USA

Re: Kit recommendation for hilly commute

Post by SurlyFRS » Sep 06 2017 8:51pm

Thanks for all the replies, sounds like everyone has a favorite option! I just used the veloroutes.org site to check the grades on my commute and the worst is 5%, but it lasts for 2 miles.

User avatar
speedmd   100 MW

100 MW
Posts: 2787
Joined: Nov 14 2012 12:16pm
Location: new england

Re: Kit recommendation for hilly commute

Post by speedmd » Sep 07 2017 12:05am

I have two mid drives that I take over some very challenging terrain and have lots of fun with them, but given your needs, I would opt for a less complex and much lower maintenance DD or even a geared hub setup as dan mentioned. Don't think you will cook even the dd on the grades your dealing with unless you push it way hard. Just cruising back and forth to work should not be a issue if you limit current-heat to what the motor can dissipate. The leaf 1500W motor may be worth a look. Nep has a good thread on it. https://endless-sphere.com/forums/viewt ... leaf+1500w

User avatar
wturber   1 MW

1 MW
Posts: 1999
Joined: Aug 23 2017 8:52pm
Location: Fountain Hills,AZ
Contact:

Re: Kit recommendation for hilly commute

Post by wturber » Sep 07 2017 4:20am

SurlyFRS wrote:Thanks for all the replies, sounds like everyone has a favorite option! I just used the veloroutes.org site to check the grades on my commute and the worst is 5%, but it lasts for 2 miles.
Yeah. We all have our own different expectations, preferences and biases. I think one of the tricks is to honestly figure out what you really want. Then try to separate fact from opinion in what people have to say in their recommendations.

That veloroute.org is an interesting site. I copied my test route into it and it says that there is a maximum grade of 20% in there somewhere. I knew there was a 10% grade, and there was one section that was shorter but steeper, but I'm a tad suspicious of the 20%. The section of my route that has the 10% grade sign is about 1.5 miles long. The 10% section is, I'm guessing, about 1/3 to 1/4 the length of the climb. Anyway, no problem with a 1000 watt rear drive - do long as you are happy climbing at about 14-15 mph.

http://veloroutes.org/bikemaps/?route=149386#
"Commuter - DC Booster"
Iron Horse 3.0 hardtail - 48V / 1000W / 470rpm generic Chinese DD Hub motor (ebay)
8 x 36v 4.3ah 10s 2P battery packs - 1500W 30A DC Boost Converter delivers 54v and about 1000 watts peak
53T/42T Sakae Road cranks - 30mph+ on flats
viewtopic.php?f=2&t=90369

User avatar
wesnewell   100 GW

100 GW
Posts: 7168
Joined: Jan 31 2011 6:25pm
Location: Wylie, TX, USA

Re: Kit recommendation for hilly commute

Post by wesnewell » Sep 07 2017 5:08am

Caliper brakes I had on a bike sucked. you can't beat a DD motor for reliability, plus you can enable regen braking with one to offset crappy brakes. And stopping fast is going to be more important a speedy takeoff. You can get a 1000W DD kit for under $200 shipped. Run it on $200-$300 of 12s lipo and you've got a very reliable setup that will top out at ~30 mph and a motor kit that should last at least 25K miles. The battery should last at least 15K miles or 4 years with proper care. I'm still using some that are over 6 years old. Now if you want to off road on really steep hills, then a mid drive would work best, but for a commuter, it's a waste of money and the maintenance will be many times more.
Need Advice? https://endless-sphere.com/forums/viewt ... =3&t=66302
Mongoose 26" Ledge 2.1 mtb bike $99, yescomusa.com 48V 1000W rear hub kit $200, Hua Tong 72V 40A controller $35, 10ah 24s lipo $217=~43mph, range=45 miles @ 20mph. 25K miles and still going strong.
Huffy Fortress 3.0 with MXUS 3000 4T motor, 24s lipo, 96V 60A controller. Total cost with extras <$700. Top speed ~50mph
My videos https://www.youtube.com/channel/UC0KW4U ... _G2wQhptMg

User avatar
dogman dan   100 GW

100 GW
Posts: 34981
Joined: May 17 2008 12:53pm
Location: Las Cruces New Mexico USA

Re: Kit recommendation for hilly commute

Post by dogman dan » Sep 07 2017 6:25am

5% grade is well within the capability of even the very small hub motors, 36v ones even, but you would climb that hill a bit slower. Eventually, pushing that small motor that hard will tend to wear it out early. June, when its hot and dry will be the time when it's most likely you will smoke that motor. But to smoke it for sure, you'd need to climb a longer hill. 4 miles of 8% will do er.

honestly, I'd go for a bit larger motor, for New Mexico summer. Unless you live at real altitude, above 7000 feet.

Your reason to consider front hub is valid, but bear in mind, you will still be climbing that hill in the highest gear you have now!!!! Really. Perhaps you might shift down 2 gears, if you have 52-11 gearing. My point is, once you motorize, you really have no need at all for 10 choices. converting the bike to a 9 speed with screw on gear is possible, but won't compare to the smooth running cassette. I ran front hubs for about 5 years for the same reason, keeping a 48-11 cassette, 9 speed.

Depending on how much you ride, and how, you might not want to ruin your favorite bike with a motor. You might consider an affordable 21 speed steel frame mountain bike for your commuter. (upgrade the saddle, and the bars) Then its perfectly compatible with the cheaper 7 gear rear motor kits.

d8veh   100 GW

100 GW
Posts: 5503
Joined: Dec 10 2010 10:45am
Location: Telford

Re: Kit recommendation for hilly commute

Post by d8veh » Sep 07 2017 7:24am

The kit you want is the 201 rpm 36v Q128C motor that will take your existing cassette, so you keep the gearing the same, then you get the 48v 17A sinewave controller, LCD, throttle and PAS from PSWPower. You can then get a 48v battery from wherever you want, like Luna or Em3ev. To keep the weight down, you should get a 52 cell one, which would give 12Ah with 30Q cells. That should be enough for about 25 to 30 miles at 20 mph if you're pedalling on a light bike with 700C wheels.

That setup is light, smooth, powerful, silent, efficient and doesn't cost much. I've fitted loads of kits with motors of every size and shape. For the riding that you've described, nothing else came close.

You need the 36v 201 rpm motor and run it at 48v to get the speed you want. I'm pretty sure that it's identical in all respects, apart from the label, to the 48v 328 rpm one, but I haven't specifically tested that 328 rpm version.

User avatar
MadRhino   100 GW

100 GW
Posts: 5959
Joined: Sep 03 2010 5:28pm
Location: Montreal QC Canada

Re: Kit recommendation for hilly commute

Post by MadRhino » Sep 07 2017 7:36am

Yep. 5% slope is a workout for a cyclist, but can barely be called climbing when you have a motor. Use the most simple, cheap 1000w Hub motor and put your money on a good battery. Upgrade brakes and tires for bigger if you can. Then you have a reliable commuter for a long time.
Make it fool-proof, and I will make a better fool.
Current bikes
Street: https://s20.postimg.org/ewrvugywt/Session_04_2015.jpg
Dirt: https://s20.postimg.org/lbqwr55ml/IMG_0157.jpg

User avatar
speedmd   100 MW

100 MW
Posts: 2787
Joined: Nov 14 2012 12:16pm
Location: new england

Re: Kit recommendation for hilly commute

Post by speedmd » Sep 07 2017 9:58am

Looks like you can significantly shorten your route hopping some curbs. :lol: Your blessed with smooth - newer roads it appears so the ridged frame setup should suffice. One thing I can tell you is once your approaching 30 mph, and the road is less than smooth, a full suspension is much more pleasant a ride. It is much more difficult to hop rougher sections with a heavier ebike setup for certain. Bigger Hubs are a bear in this respect. My Santa Cruz blur bbs02 rides like a Cadillac on the road. Seriously plush! Agree with others that good brakes are a must. If your able to try a few different setups, you will know much better which you wish to live with long term.

Post Reply