Someone needing e-bike help on bike forums

General Discussion about electric bicycles.
Hasaf   10 mW

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Someone needing e-bike help on bike forums

Post by Hasaf » Apr 06 2012 9:53pm

I looked and say that it is not against the rules to link to other forums; so here goes.

I have been following a thread on bike forums at http://www.bikeforums.net/showthread.ph ... -surprises! where a person is having a very specific problem with her e-bike. I do not know her; but, I felt that the people here would be better suited to help her than the bike forum crowd (who are generally suspicious of e-bikes anyways).

I directed her to this forum, where she will probably get better answers. However, if anyone has anything to add to the discussion going on there I would be interested in the solution too. Living in Ashland, OR (when in the states) I know that the solution for getting an e-bike up a steep hill is to pedal harder. She is looking for more advice than that.
Last edited by Hasaf on Apr 07 2012 9:56pm, edited 1 time in total.

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Re: Someone needing e-bike help on bike forums

Post by dogman dan » Apr 07 2012 8:18am

Since you are on that forum, tell her to look here at the Wife Kit in for sale new, that Methods sells. She may even need more than that, but a 2810 nine continent on 48v will climb pretty steep hills. But there are hills in SF it won't climb, that's for sure.

The other thing that would have a chance is a Mac from cellman. I think he has them as slow as 12t.

She needs a slower winding and 1000w, or 5000w, one or the other. A medium fast winding on 500w is born to fail on steep hills, but those frockers sold her one anyway. :evil:

She can read plenty here about that wife kit, in my 2810 threads, and contact Methods at his website, http://www.methtek.com/

She should be able to get up 15% grades on the wife kit, using 48v and just a bit of pedaling. About 1200w, and ability to stand speeds as low as 10 mph up steep hills.

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Re: Someone needing e-bike help on bike forums

Post by Pure » Apr 07 2012 9:55am

Not to mention, ready made e-bikes are usually over priced with exaggerated power and distance claims. Have her get a comfy cruiser, and put a slow winding Mac motor from cell man on it ( great for hills). Then go with a 48V15A Ping. Use a CA to limit amps to 25A. If she is hesitant at 30 mph, then again with the CA limit her speed to 20-25mph. The extra voltage should still help give her decent acceleration, but not enough to be scary, especially on a geared hubby, pull less amps. I'd go with the ping for the plug and play simplicity, and I don't see her wanting to pull 90 amps off the line with LiPo.
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Re: Someone needing e-bike help on bike forums

Post by dogman dan » Apr 07 2012 10:39am

That ping and 48v 20 amps controller is my setup on my longtail, with the 2810 motor. Pulls me up 10% hills with a heavy load just fine. The top speed at 48v with that motor is 19-20 mph, which she may not mind anyway. If she did want some speed too, that motor really perks up on 72v 20 amps.

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Re: Someone needing e-bike help on bike forums

Post by kriskros » Apr 07 2012 1:44pm

on bike forum i gave some info to about 6 or7 people and suggested they go to ES for more details... i was permanenntly banned for spamming :roll:

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Re: Someone needing e-bike help on bike forums

Post by Should be working » Apr 07 2012 2:49pm

Hi everyone,

Thanks Hanaf, I'm the poster from the bike forum with the problem. This board seems a lot more technical and specialized than that one, so I have a lot of terminology to learn.

Here's the summary: I'm a 5'5", 140 lb, 45-yr-old woman with steel in my hips that can't bear the strain of hard biking. I have biked around flat cities without problems, however. I live in the east bay (Oakland hills) and would love a bike for commuting and errands and light exercise within about a 6-mi radius to my house. But my house is on the top of a steep, long hill. I mapped out the several ways up the hill with "Ridewithgps" and it showed grades of 13% for stretches of at least 1/4 mile and also short stretches of 29% and a lot in between, and also stretches much lower, as in 4%. There is one much longer detour I can take that has grades of about 5%.

I did a lot of research, ended up with an Ohm Urban, which seems entirely unable to climb the hill on any but the long detour routes. I tried a few and ended up calling my husband for a rescue. The shop is very helpful and willing to work with me, so they are bringing some other bikes to try next week. I hope they work because I am not a techie, have no idea about bikes, and just want to get riding!

As for speed, as some of you indicated, this is not at all important to me. I get anxious going more than about 12 mph downhill anyway, and uphill at 6-8mph is fine. I like an upright, comfy ride. I like regen brakes, as with my Ohm, because they slow me down so well on downhills. I prefer a low step-through because my hip is a little restricted in motion. Again, I'm going to use this bike to go to work, in my nice clothes, carrying also computer, lunch and so forth. Maybe there is no bike that can do this.

Not sure what a Mac from Cellman is, nor the 2810, but I'll start researching. Any tips are welcome, and if you want I'll keep you posted about what the bike shop brings me to try. They suggested a Focus and a 2011 Ohm, which doesn't overheat as quickly. Over on the other forum I got recommendations for Ecospeed, Crystalite and Cyclone kits. But then I'll have to figure out what kind of bike I want.

Thanks for all the generous responses, and to Hanaf for referring me to this board.

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Re: Someone needing e-bike help on bike forums

Post by dogman dan » Apr 07 2012 3:09pm

Glad you showed up here.

29%, Ouch! I'm not so sure even my hottest dirt bike would do that. If it's more than a few feet, you may be stuck walking up that. No way that bike shop is going to have anything that can handle it. But we can help you create a bike capable of the 13%. If you can just find a route around that 29% stretch you will be good.

The wife kit is here. http://www.methtek.com/ I think he still has a few of the 2810 winding 9 continents left. If they aren't listed there on his website, look in the for sale new section here for a wife kit thread. If you run one at 48v, you may still have to pedal just a bit up the 13% grades if they are very very long, but not hard pedaling. Just enough power to keep it moving 10 mph.

The idea here is twofold, with a 20 amp controller, you are having 1000w. That's the bare minimum to get up steeper hills. Nothing "legal" is going to do it. But nobody is going to notice you have that power because this motor has such a slow top speed. 20mph on 48v. The slow motor is able to tolerate the slower speeds you have when going up steep hills. Normal motor windings require the motor to move 15 mph or more up steep hills, or they overheat and melt. So between the extrat power and the ability to tolerate 10 mph speed up hills, the slow winding will climb much much better than a typical ready to ride bike.

The Mac motor has planetary gears inside, so it's also able to tolerate slower speeds because inside it, the actual motor is spinning much quicker. A good vendor for those is here. http://www.emissions-free.com/ The Mac also can be had in a slower than normal winding, making it a good choice for climing steeps.

Lastly, there is a proven San Francisco bike. It's called a stokemonkey, but I'm not sure you can still get them. They mount onto a longtail cargo bike, and by running a motor through the chain, allow the use of extreme low gearing to get up the hill. Ideally, you run them at 48v, which again gives you 1000w of power rather than being limited to 750w or less.

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Re: Someone needing e-bike help on bike forums

Post by dogman dan » Apr 07 2012 3:20pm

Here is the stokemonkey site. You can at least see what I'm talking about from this. Haunt the craigslist, if you see one for sale used, jump on it perhaps.
http://clevercycles.com/blog/products/stokemonkey/

There are other motors that go through the gears, R martin bikes for one. But none had the power of a hubmotor like the stokemonkey did.

One last option for a ready made bike that can climb hills is the Hanebrink. Not very bike like, but a hell of a climber. http://www.designboom.com/weblog/cat/16 ... -bike.html

As you can see, this is also a stokemonkey style rig.

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Re: Someone needing e-bike help on bike forums

Post by Should be working » Apr 07 2012 4:06pm

Thanks, Dogman. Ebikes.ca has some negative evaluations of the 9C motors, but that is for the 9c 280X, which I guess is different from the 2810--or is it? Why is it called a 'wife kit'? Ebikes.ca seems to like Crystalite. Never heard of the Mac motor before this forum, looks good--why is it seemingly not well known?

Hanebrink is too weird for me. I want riding to be fun, this would make me feel like a freak show. Too bad the Stokemonkey is out of stock for now.

I can find routes to my house that have a lot of 8-12% and then some spots of 16-17% grade, would that burn out or outdo any of these motors? Ecospeed is a fortune but seems reliable. Is it better than Mac? Ebikes.ca seems well regarded on this board, so I guess I would either use them or Ecospeed. There's also ebikessf.com, which uses BMC. Any word on that?

Also I do NOT want to put this together myself. I know you all say if I can tie my shoes I can do this, but it will definitely lead to frustration and even marital strife!

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Re: Someone needing e-bike help on bike forums

Post by dogman dan » Apr 07 2012 4:41pm

Actually, it is harder than tying your shoes. So you'd need help to build a bike. Where you are, there are a few folks you might be able to turn to for that help.

It's not the 9c motor per se that is a problem. Just that the typical 9c or 9c clone bike kit, which uses a 2807 motor is not designend to climb anything steeper than about 10%. 10% is where most state highways max out, though city streets and driveways can be crazy steep.

Wife kit, is just a marketing tool Methods was using to sell off his overstock of 2810 motors. Here on ES, so many people are just plain into speed and power, and they weren't selling so good. They are my favorite motor for a commuter or touring bike though, because they don't overheat on a steep hill. Fed just enough wattage to stay just under the melting point, they make a fine dirt riding motor as well. They are a slow motor, so the 40 mph club wasn't interested in them. I'm the slow motor fanboy here. But I have mountain and desert trails nearby, as well as roads that are steep. So I fell in love with the slow stuff that climbs great.

For the 9continent 2810 motor, when run on 48v 20 amps, they do quite well on grades up to 15%. Above that, you must begin to pedal very hard.

I know of no affordable ready to ride ebikes that can climb what you need, (29%). But one that does quite well on hills is unbeaten on the pikes peak bicycle race. That is the Optibike. http://optibike.com/

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Re: Someone needing e-bike help on bike forums

Post by MadRhino » Apr 07 2012 5:33pm

Since you are not likely to build one yourself, I believe that you should find someone to build a custom Ebike for you. You should pay a visit to Ilya (Ebike.sf), for he is local and has the knowledge to build what you need. I have bought motors from him and had very good after sale service, and I know some here on ES who had him build their mountain Ebikes. I know that he has Chrystalyte and BMC motors in stock, maybe some more options too. He sometimes advertise in the sale section of this forum, and is a long time trustworthy member.

The simple fact that he is in SF makes him a good resource for you. He knows the hills that you are talking about, and will tell you exactly what you can expect with various building models, and motor-controller combinations. Then, having a reliable local Ebike specialist is precious to one who doesn't want to build and maintain his Ebike.
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Re: Someone needing e-bike help on bike forums

Post by teklektik » Apr 07 2012 5:38pm

+1 for Ilia!

Knowledgable, outstanding service.
Check out his site at ebikessf.com to see some of his builds.
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Re: Someone needing e-bike help on bike forums

Post by Should be working » Apr 07 2012 7:31pm

Thanks for those tips as well. I phoned with ebikessf the other day to make some inquiries, and they told me to come in a few weeks, I guess they are busy opening a storefront and a bit preoccupied at the moment. The guy I got on the phone recommended I start with a Rans, some kind of near-recumbent or a Breezer, all brands I don't know. So I'll need advice first on what bike to get before I get the kit. Whomever I deal with, I''ll want to know that they will take it all back if it doesn't work on the hill. Ecospeed was also helpful on the phone. They claimed that the Optibike uses the same technology they do, just built around a highest-end bike (hence the Optibike's $8K price, which I can't pay). And then there is the 2810 and the Mac and possibly the BMC or Crystalite to consider, all less $$ than Ecospeed.

I talked with a biker acquaintance today and he pointed out that I've been riding a 52-lb ebike up the long, gradual upward detour at about assist level 2-3, and he rides that stretch all the time with his 17-lb bike without much straining at all. I don't know if the 35-lb weight difference betweem our bikes would mean that I could also bike a light, non-e-bike up that detour with relative ease. He is in good shape--but it is a known route for bikers, even my out-of-shape husband did it a few times. But if that's the case, the last resort here is to give up on an ebike, spend $2k on a really nice, light regular bike, and ride the long detour home a few times a week for a workout. It's not what I really wanted but it is some biking for exercise and sort of a commute option.

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Re: Someone needing e-bike help on bike forums

Post by Hasaf » Apr 07 2012 10:05pm

kriskros wrote:on bike forum i gave some info to about 6 or7 people and suggested they go to ES for more details... i was permanenntly banned for spamming :roll:
Understood, I do not frequently point people here; however, she was having such a unusual problem and the people at BF were clearly over their heads. In this forum there was someone who, right off the bat, was able to start talking to her about optimal motor windings and such.

The only problem here is that people often get so would up the the minutia of searching for the ideal that they forget to ever say, in simple terms, "here is what you need to do to make it work. . . " It is often a classic case of "The Best" becoming an enemy of "The Good."

That being said, in this case, a discussion of the ideal motor was in order, and that wasn't happening at BF. Here is what I posted there. So far there have been no complaints about the way I worded it:
I hate to say that you are asking at the wrong place; but, the experts in this hobby are at endless sphere. It sounds like the issue is the final hill. To meet your needs you may need a custom build. The good news is that a custom build is within your price range.

There are two directions that a custom build may go. The first is the simple application of more power. The factory built e-bikes are limited by the lowest, permissible, legal power and top, unassisted, speed restrictions. A custom build may exceed the power and limit the top speed through a governing device like the cycle-analyst. Another direction a custom build may go is to use two hub motors (this is because you have ruled out the eco-speed mid-drive due to cost). One of the primary reasons for two hub motor solution is to control, and spread, the heat buildup on long hills; exactly the situation you are facing. There are also other, lower-cost, mid drive solutions that a custom builder may be able to discuss with you.

I know you have expressed that you want an "off the rack" solution; but, those solutions may not meet your needs. Many custom builders can also provide you with a high quality solution that will provide years trouble free transportation. The simple facts are that e-bikes are the cutting edge of local transportation devices; however, the operative word here is edge. You may need to work with a builder to find the best solution for you. Again, I recommend that you ask these questions at endless sphere. You have an expert level problem, go to the experts.

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Re: Someone needing e-bike help on bike forums

Post by Should be working » Apr 07 2012 10:24pm

Hasaf, I'm glad you did point me over here. I don't exactly know what a motor winding is, or planetary gears, but now I know that it should be slow-winding for going up hills if I don't care much about speed. And the Mac and 9C2810 are good tips.

The funny thing is, I thought my problem would be completely USUAL and easily answered--I want an ebike to go up a big, steep hill! What could be more common than that among ebike owners?? But it does seem, as was said on bikeforums.net, that readymade ebikes are not actually made for steep-hill-climbing!

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Re: Someone needing e-bike help on bike forums

Post by fechter » Apr 07 2012 11:20pm

A Mac and a BMC are really the same thing. These are internally geared hub motors. For really steep hills, they may be the best bet as long as you get one with a slow wind.
Setups that go through the bike gears are the best for hills, but tend to be quite complex and expensive. It sounds like a single speed will be fine for your application.

29% grade is incredibly steep. I'd have trouble walking up that. Most bike motors won't survive more than a minute or so of that. 17% is much more reasonable. My BMC powered scooter (not a hub motor) can handle grades over 25% at something like 20mph. Geared for a slower top speed, there is less likelyhood of overheating the motor, which is your biggest concern with steep hills.
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Re: Someone needing e-bike help on bike forums

Post by MadRhino » Apr 07 2012 11:39pm

Should be working wrote: The funny thing is, I thought my problem would be completely USUAL and easily answered--I want an ebike to go up a big, steep hill! What could be more common than that among ebike owners?? But it does seem, as was said on bikeforums.net, that readymade ebikes are not actually made for steep-hill-climbing!
Readymade Ebikes have to comply with legal power limits, none street legal Ebikes off the shelf has the power to climb a 29% incline. Some can be upgraded to do it and some that are classified "offroad" could do it but generally, those who are after that kind of torque build their own with either one of the 2 solutions: Gear down or feed a lot of power.

Climbing that steep is very hard on the Ebike's components, motor and controller. Building such an Ebike requires someone who has the knowledge and experience to balance power and efficiency, to make it reliable. Building one for a rider who is not the kind to ride a torque monster wheelie machine, is even more complicated. My bikes can do it, but their power would scare you. You need a rig that is made to climb moderately, with a geometry to do it comfortably, and that leaves very few options.

You are lucky to live in a region where Ebikes are popular, and specialists can be found to build what you need. Most of those who buy an Ebike to solve this "usual problem" never find an answer and give up.
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Re: Someone needing e-bike help on bike forums

Post by john7700 » Apr 08 2012 12:40am

A custom E-bike will fulfill your needs. You are obviously going to have to work with some one. An individual with decent bicycle skills and even minor electrical competency can put a conversion kit on for you. An E-bike shop will probably be best in your case however. What you will/are running in to is the fact that it is the middle of March, the weather is great and every one wants to go for a ride. It is kind of like looking for a new tax guy on April 10th. Shops are swamped and new projects will have to wait in line. Do some more reading here on commuter and hill climbing bikes. Get an idea of what your looking for and you will also start to get some ideas on pricing. Armed with a little bit of knowledge, go down to the shop and kick a couple of tires. Let the shop guy know you are serious and have some idea of what you are looking for and this will get your project rolling.

I think a lot of the advice you have gotten here is spot on. A slow wind motor on 48 volt Lifepo (higher voltage/different battery chemistry will get way to complicated) on a woman's comfort/mountain bike is probably going to be your solution. Remember, this is not off the shelf and is going to be a project that you will have to work on with your mechanic. To round ball prices I would think you are looking at around $1,500-1,700 for the kit and instillation plus the cost of the bike.

This is a lot of time, energy and expense but I assure you the E-bike experience is worth all the work. Please keep us posted on your progress and choices. You'll be sporting that E-bike grin before you know it.

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Re: Someone needing e-bike help on bike forums

Post by dogman dan » Apr 08 2012 6:51am

Funny isn't it, that ebikes aren't made for hills eh? I think to some extent, the ebike laws have produced that. Nearly every place has a law limiting watts to about what a racer in the tour de france can put out for a few minuites. So the ebikes come out with 750w, and ability to climb the typical TDF race route, about 10% grade maximum. The really low power stuff may max out at even lower grades, like 7%.

Too bad the approach wasn't to allow up to 3 hp, around 2000w, but simply limit top speed. Then everybody would be putting out powerful bikes but limiting speed one way or another, and we'd all be breezing up steeper hills legal. One of the reasons I became a slow motor fanboy is that my state has exactly that kind of moped law. 8)

But if you live in San Francisco, you are basicly screwed. 29% grade is crazy steep. In degrees, that's 16 degrees, or on a ski slope blue square.
I won't say a slow winding motor will climb that easily with 1000w, but with hard pedaling it can if it's short enough. I know for a fact you can get up 13% quite easily on the 2810 nine continent, a 48v 20 amp controller, and a 48v battery. So your solution is going to be a relatively high wattage, at least 1000-1500, and a route around that 29% bit that is closer to 15%.

Definitely get a hold of Ebikes SF since they are close. There are other members in SF as well, who might help out if you start a thread asking specificly for that. I belive Methods, who has the 2810 motor is not so far away by car too.

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Re: Someone needing e-bike help on bike forums

Post by BikeFanatic » Apr 08 2012 7:14am

I think you have a lot of good information posted already. Lower speed hub motor seems to me the simplest and best. You
could order the motor from Methods, cellman, or Ebikes.CA then have the shop mount it for you. Cellman sells batteries as well.
I would get 48 voltage and 9-11 AMP hour ( amp hour is size).

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Re: Someone needing e-bike help on bike forums

Post by Should be working » Apr 08 2012 12:25pm

Thanks all. John, your optimism is encouraging. I hope it isn't misplaced. I studied my ridewithgps.com routes some more. FYI the 29% sometimes shows up as 24.6%, so maybe the software isn't consistent? Anyway that's just one little spot near my house where the road "dips", because there was a small landslide some years ago and they just paved over it, thanks a lot Oakland. My kids love to accelerate through "the dip" when we drive down to school.

The only way to bypass "the dip" but come relatively directly home is to take famous Claremont Ave to Grizzly Peak, which is a relentless uphill at around 8-13% with tiny peaks of 16%, 19.8%, 19.2% and 23.5%, if ridewithgps is reliable. But again the question is whether any ebike motor could do this for 2.4 miles without overheating.

If the short "dip" can be managed by a bike, meaning I don't have to go up Claremont but can take the small, winding routes to the "middle" of our hill, I can do routes of about 11%, with short peaks of either 18% (with slightly longer stretches of 15%), 16.1% (also with longer stretches of 14%), or one route that is only about 13% but has a brief peak of 27%!

If you PM me I can tell you where I live and you can see the options for yourselves--essentially I live on a small mountain with only 3 roads that go downhill off of it (hence people died in the 1991 Oakland fire thanks to clogged roads) and one road that goes UPhill to the Grizzly Peak ridge (which I can reach with my Ohm with a 6-mile detour up a gradual climb). The Claremont Ave option takes me fairly directly up to the ridge, and then I come down to my house.

If the bikes that the shop brings don't work on the hill (and I am skeptical), I will go to ebikessf, since people here have high recommendations. My hope is that they will agree to take back stuff if it in the end doesn't work. As Fechter's tagline summarizes it, all my data analysis of grade and your estimates of motors won't mean much if the bike isn't able to get me home.

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Re: Someone needing e-bike help on bike forums

Post by dogman dan » Apr 08 2012 1:06pm

It can be done. But what it takes might be techically illegal in CA. My dirt bike climbs 15% no sweat, but it runs on 1500w, not 750. It uses the now unavaliable 2812 rear hubmotor. Crazy slow, but it will climb. I almost never pedal a stroke while riding it. It runs on 72v.

One option not mentioned yet, is the tiny wheel. Bikes with 20" wheels have a big advantage. Maybe at Ebikes SF they can set you up with something using one of thier powerful gearmotors, but laced into a bmx bikes 20" wheel. Then, with some frame bending, you could run it on a folding bike of some kind, or a recumbent that has 20" wheels. There are delta trikes, the kind that have two front wheels, that climb nearly anything.

Chances are, your climb will take money, but it definitely can be done. If you can take that bump on momentum, that changes everything. Building to climb 15% is definitely doable.

Another approach that works, double motors. Basicly, double the power, so you climb fast enough to avoid the overheating problem.

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Re: Someone needing e-bike help on bike forums

Post by Should be working » Apr 08 2012 7:25pm

Ok, so now I've been trying to understand ebikes.ca's simulator. The BMC seems to give great high torque at low speed, but the power level is weirdly low (I'm trying a 16% grade), does that make sense? And what is "load" and does it matter?

Also, would I be looking at a 20A controller or a much higher one?

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Re: Someone needing e-bike help on bike forums

Post by MadRhino » Apr 08 2012 7:51pm

Should be working wrote: Also, would I be looking at a 20A controller or a much higher one?
To make a climber, you have to feed as much power as the motor actually can take without frying. 20 Amps with a slow motor makes a safe climber for moderate hills. To climb 15% it would be OK, but for 30% you need much more. All my bikes are good climbers with upgraded DD hubs, and all my controllers are set 100 to 150 Amps. They are mountain sport aggressive machines, not something I'd recommend for you. If you have the power to climb 30% incline with a hub motor wheel, your bike will lift the front as soon as you give it a little too much throttle. With a Stokemonkey setup, you could have a very good climber that will not need a lot of brute power, safe and comfortable to ride.
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

Should be working   100 mW

100 mW
Posts: 38
Joined: Apr 07 2012 2:25pm

Re: Someone needing e-bike help on bike forums

Post by Should be working » Apr 09 2012 12:21am

Stokemonkey seems to have gone out of existence for now, at least by Grin and Clevercycles. It looks like it's a mid-line motor like Ecospeed. There is something called an E-4 that seems to be similar. And that is what the non-hub motor forum is about that I haven't studied much yet.

Controllers" So the motor has a certain amount of power it can take without frying, I guess that's determined by the motor, so you pick a controller depending on what the motor's safe intake is. Got it. Thanks. Now when I look at motor descriptions it looks like you can pick out different controllers, where does it say how much power the motor can take? Or I guess this is where the ebikes.ca simulator would be used to show after how long the motor would overheat. Or is there a standard way to know this?

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