Faddy Daddy

As a preface, I am only considering this so please formulate your responses accordingly, i.e. please don't spend too much time as of yet

Anyhow, I have a Novara safari (2008 ish I believe) touring bike that I thought might be interesting to transition to an ebike, more or less for a fun project. On one hand I still feel a bit like it would be cheating somehow, on the other if I'm thinking about towing our littlest in the wagon it would be a huge assistance. I ride some roads but mostly try to stick to certain bike paths in our area. And one might not think it but some of these can be quite hilly, switchbacks and all! There are also some rails to trails paths, such as banks to vernonia if anyone lives in Oregon which are a lot of fun, it's 21 miles one way with a nice gradual slope, but still, pulling a wagon gets tiresome! If I do embark on this project I'll probably loose the touring bars and go for flats as it looks like I might need to loose the twist shifters.

So first, and I feel bad asking this as I'm sure it's been covered 1,000 times but either a hub or mid drive. More specifically I'm curious about the throttle on a mid drive motor. Does it automatically give full output? I mean say you are pedaling along at whatever, say 50% boost. From what I can tell the motor is already engaged at this point, so what does the throttle do? And because the power goes through the bikes existing chain and drive, it's obviously useless when coasting, (one reason I think a hub motor would be fun, to have that sensation of power when just coasting). On some could you perhaps program it for an added boost in power? I do love the idea though of easy tire changes and wheel maintenance, not to mention using the bikes gearing for good power on a slow climb with switch backs. My understanding is hub motors need to be turning at a decent clip or you'll really stress them going slow. Difficult to do on slow switchback climbs maybe not even reaching 5mph. So I think a mid mount is probably a good way to go for me, but I still want to know about the throttle and it's purpose. Also, a kit I looked at, and from other reading, they come with their own brake levers to cancel the motor when braking. This also confuses me, I mean if you stop peddling doesn't the motor stop as well or is it not instantaneous creating lots of heat or something? I'm probably missing something here, but as of now I don't see the need or understand?

Further, can anyone recommend some shops or nice places to get kits. I came across Luna cycles, I still can't figure why they are almost half the cost of E-Rad? (For a BaFang BBS02 750W for instance). One article I read claimed because E-Rad has shift sensing, but I see Luna cycles also has a sensor for this, ($45). And from what I can see 750 watts looks like the least powerful Luna cycles is selling now, isn't this massive overkill? Of course they do look rather set up for speed freaks, ha ha, claiming right on their site they can hot rod (reprogram the firmware) in the controllers for much more speed, (off road only of course). And they seem to emphasize 48 or even 52V batteries. I also find this confusing because lots of the prebuilt bikes, at least on the lower end seem to max out at 500 watts and maybe 36 volts, (on the little bit of looking I've done).

Well, I guess that's a start if anyone cares to set me straight on some of this stuff. Oh, not sure if it matters but a $1k budget is what I was hoping for, (if I even choose to go this route), that's what attracted me to Luna cycles.

NoPhart

I just happen to be checking in this Sunday evening to see what's new here, so I'll get you started with a little BaFang Mid-Drive knowledge as I have a 350W/37V model on my E-bike.

"Well, I guess that's a start if anyone cares to set me straight on some of this stuff. Oh, not sure if it matters but a $1k budget is what I was hoping for, (if I even choose to go this route), that's what attracted me to Luna cycles."

BaFang and battery come in right at your price point if you install it yourself. I "think" the E-Rad are BaFang's with their own case cover. Personally I'm not aware of any differences (?).

"More specifically I'm curious about the throttle on a mid drive motor. Does it automatically give full output? I mean say you are pedaling along at whatever, say 50% boost. From what I can tell the motor is already engaged at this point, so what does the throttle do? And because the power goes through the bikes existing chain and drive, it's obviously useless when coasting, (one reason I think a hub motor would be fun, to have that sensation of power when just coasting)."

"My" BaFang is set to use the power level (1-5) that you are using when you hit the throttle, but it appears to take the motor to peak output at that level. The 350W/37V/18-20A built-in controller can put out about 680W's of peak output even though it is a 350W motor. I've been told that the throttle level is a setting within the controller and that you can set the throttle to always go to maximum peak power (IE: level 5) no matter what setting you are in, but have never looked into confirming that (?). I work around it by just clicking the "+" button up to level 5 if/when needed.

THE THROTTLE IS NOT USELESS WHILE COASTING. In fact, you can use the throttle like a moped or motorcycle when coasting at all power levels. The throttle overrides the magnetic speed/cadence sensor on the rear wheel spokes. It is worth noting that this feature is very useful when climbing a steep hill and your cadence slows to the point of cutting power; just hit the throttle and power assist continues (and in my case at a higher peak power output - My system was setup by Tim at BM E-Bikes, not by me).

It is also worth noting that BaFang Mid-Drives don't have torque senors. "IF" they had a torque sensor, the power would never cutout, because the pressure on the pedals theoretically would tell the motor your are trying to pedal. Rumor has it that BaFang is working on a torque senors for their mid-drives, but again I can't confirm that or if the aftermarket torque sensors can be added if desired. Like I said, the "easy" work around is just hit the throttle and keep pedaling!

"Also, a kit I looked at, and from other reading, they come with their own brake levers to cancel the motor when braking. This also confuses me, I mean if you stop peddling doesn't the motor stop as well or is it not instantaneous creating lots of heat or something? I'm probably missing something here, but as of now I don't see the need or understand?"

The motor stops when you stop pedaling after the time period "SET IN YOUR CONTROLLER." This is another area I have not explored. There is a known "TUNE" out there that many people use and claim is optimal from their personal experience that can be downloaded. If interested I'd try Googling it.

I've never had any heat problems even with throttle only use. Heat problems usually only arise when people start over volting/watting/amping their motors to add power. At the BaFang stock settings you shouldn't have any issues. Others can tell you where to look for those heat related bounderies, but frankly I don't need anymore than level 3 on a 350W/37V motor for normal flat riding or more than 680W's with throttle and pedaling on the steepest of climbs off-road. I imagine a 750W motor with about 1200W (guessing) peak power will be more than you will need as well. I think the reason the 750W BaFang has become the norm is the 250W-750W BaFangs are all the same price, so Americans go for the maximum and find they use even lower assistance levels for normal pedal assist. IIRC you can set up as many as 9 levels of assistance.

The brake sensors instantly cut power when you hit the brakes; overriding the preset delay in the controller. There are manual cable ones and hydraulic ones available, as well as, shifter cable sensors if you desire them (I do not have shifter sensors and don't need them). Many BaFang E-Bike riders don't even use brake sensors at all. They feel less-is-more and don't want the additiional wiring; some don't even want the LED readout screen and put it in their battery pack bag out of site. What they do is set the speed/cadence sensor at the fastest optimal time cutout that they prefer. Once again, I haven't tried this, but want to in the future, because I hate all the wires and even at my current setting it cuts out pertty quickly. I am all for the less-is-more concept.

That should get you started. I'm sure others will chime in too. Good luck in your hunt and research. Be sure to get out and ride one if you have access to test rides. Wow-Zer!

Faddy Daddy

Thanks NoPhart, you did indeed provide me a ton of useful info. In fact, I think I was reading your post about your build (very nice write up by the way!), when I got some of the throttle questions, (or perhaps I was mirroring some thoughts you pointed out in your post, either way...). I could be wrong but I think you had mentioned that the throttle typically only outputs what "step" it's set on, and your description here helped me visualize it a lot better. It would make sense to me if it were an adjustable setting. I would assume it would be useful if you could set the throttle to exert the max power, say to help over a short hill. Of course I might just be trying to avoid pushing a lot of buttons quickly, ha ha, I could see myself fumbling with that for sure, a quick throttle kick might make it easier for me.
OK, now the coasting part, but you still have to peddle don't you? (even if very lightly?). I guess what I am getting at, is if you pick your feet up completely off the pedals, (perhaps crossing a shallow stream for instance), will the mid drive continue to rotate your cranks? If so, that would be awesome but I had initially pictured it differently, that you still had to rotate the crank, no matter how lightly. This is one of the few advantages I saw about a hub drive, but I might be visualizing it all wrong.
Finally, on the brakes, again it makes better sense that there is a cut out delay which can be programmed. I would imagine if I accidentally stuttered, or going over a bump or something that I might not wish to loose power. However, I still have the premise of the crank continuing to turn. Let's say I programmed a 2 second cut out delay, (I don't know why, just as an example). Then let's say I'm peddling through some weeds and perhaps some burs or stickers get on my shoe lace or sock. Obviously if I wanted to play it safe I should stop and remove them, but lets say I'm falling behind my buddies as it so, so I just want to reach down and remove them, if I stop peddling the crank would it continue to rotate for the 2 seconds? (unless I hit the brake I guess), thereby rotating my foot out of reaching distance?
Huh, I'm getting too wordy, sorry. I guess I'm asking is do you ever find a time where the crank continues to turn under the motors power when you weren't expecting it too?
Again, thanks so much for your reply. You've really helped me start getting a better mechanical grasp on these mid drives. I'm probably best to try and find a demo somewhere, but heck, I think I would have fun just installing it regardless.

NoPhart

Let me try to make this simple. On a normal bicycle, if you stop pedaling the bike continues to roll forward and you can even backpedal. It's the SAME on a BaFang Mid-Dirve. If you stop pedaling the bike will continue rolling with assist (you can backpedal while the assist is on) only as long as the shut-off delay setting. After the motor stops assisting, the bike will continue rolling and you can even backpedal just like a normal bike.

The brake shut-off only overrides the preset delay setting. If you are already past that time period, the electric assist has already stopped. The brakes will just slow the bike like a normal bike, because the electric assist has already been cut by the shut-off delay.

If you want the bike to continue "powering" forward with the electric motor, just hit the throttle. This is an example of how the throttle can come into play; a circumstance in which you want to continue powering forward while you pick the thorns out of your shocks or check the kid or avoid a pedal strike or etc... And while you throttle you can even backpedal if that's your thing or you want to get that leg cramp out.

The BaFang Mid-Drive kit is a really neat setup. If they added a torque sensor option, well even better, but not really needed.

Take a look around the electricbike-blog.com site for some real world in the outback testing until it breaks analysis. He's leans hard towards the high powered bikes, but his testing and findings are very helpful even for someone like me that has no desire for anything bigger than a 750W California Legal E-bike.

As you can see by my new custom build in progress, I've moved to the less-is-more approach with 3spd IGH and 33% gaps between the gears; really being used as a 2spd with granny gear for climbing when needed. I want to try resetting the brake shutoff delay to what others are using and disconnect the brake shutoff senors to see what it's like. I haven't decided if I will run the proven trouble free Avid BB7 cable brakes or hydraulics yet. Belt drive will eliminate chain maintenance too. Fun project, but steep learning curve on the electric side of things. All well worth it IMHO.

Faddy Daddy

NoPhart,

Thank you, thank you, thank you. I THINK I just had a revelation thanks to your patient explanations.
I think where I have been going wrong, and it's hard for me to tell from the pictures I can find of a BaFang, but I had ASSUMED that the crank arm is permanently attached to the drive sprocket, as on a standard bike. If the sprocket is turning, so is the crank arm I kept telling myself, ha ha.

But from your explanations and looking again and again at the picks I am thinking the crank arm can turn independently of the front or drive sprocket, if so, just as you have been saying, this is awesome! So just as you've been saying, you can use the throttle while you coast, etc etc.

Wow, that just eliminated my last thought about a hub drive, sorry about all the difficult questions and I hope you can see where I went wrong... I just had it fixed in my mind that the arm and sprocket were permanently attached as on a standard bike, jeez!
Well, thank you though, my questions have been quite happily answered!

slomoshun

You are in Beaverton, Oregon. Try Portland Electric Cycle hub motors in Portland.

Doc_Wui

I have the Bafang BBS02 on my old Diamond back. The pedals free-wheel with throttle. You can even pedal backwards and nothing happens. Of course, this obviates the use of a coaster brake hub.

I don't have anything other than my own feeling to prove it, but I believe this bike pedals like a normal bike when the pedal assist is turned off, or if the battery is disconnected. In fact, I had to pedal it 18 miles when the battery connector fell off (didn't figure it out til I got home). Other users say there is some pedal resistance.

I ride my ebikes 100% in pedal mode, and often with the pedal assist off, but a spurt of throttle can always be applied for a little help up hills, etc when assist is off.

I have the lunacycle kit. The number of PAS levels is user adjustable. At 5 levels, I found level 1 would get me to 18 mph, so I switched to 10 levels, and it's more like 12 mph. My description of PAS is that it's like power steering. Pedals are just easier to turn. If you want to treat the motor nicely, use the gears like you didn't have a motor. Just as you will kill yourself going up a hill slowly in top gear, you can overheat the motor doing the same thing.

The BBS02 is relatively easy to install if you have ever removed a BB. I had to use a rotary file to take some casting imperfections in the frame.

I have towed an easy step trailer with my grand daughter in it. With or without power on the flats, it tows so easy that I need to mount a mirror to make sure my little passenger didn't bail out. I cannot feel the weight.

Now, if you want to get into a hub motor, you can save a couple of hundred dollars on the total package. I've got that kind too, albeit they are lower power geared motors. I feel that a 500W geared motor and 48V battery can handle any hill that a suburban rider can handle.

Faddy Daddy

Thanks Slomoshun, I will give them a look but I'm thinking at this point if I do decide to pull the trigger I'll go with the BaFang BBS02 (750W) from Luna cycles. Their prices seem decent from what I've seen.
Also thanks for the recommendations Doc Wui, I was thinking the 500w as well, but Luna only has the 750 or 1000 watt at this point, certainly should be sufficient!

Yeah, my wagon, a Burley pulls really well too. It's only on hills that I begin to notice the weight. That's where some assistance would be nice, but I'm really just wanting to try it for the fun, or to make further destinations more accessible.

And ... I also want to take this opportunity to apologize to all, (especially those that read and tried to understand my earlier questions, like NoPhart!). I'm a tad embarrassed to admit, but I honestly thought on the mid drives the crank arm was affixed to the drive sprocket! This is why I had such a hard time understanding the coasting and throttle thing. If I go out in my garage right now, I've got my 26" safari, my wife's specialized crossroads, a tandem, a kids 20" and 2 kids 24 inchers and on each and every one the right side crank arm is affixed (more or less permanently) to the gear, go figure! So I assumed the mid drives were the same as I've never seen one up close. Anyhow, again thanks to NoPhart for helping me figure that out, that the crank arms, or peddles one might say, actually can spin independently of the drive! Doh!

dilkes

I have a BBS02 750 watt on my fat bike and it works well. However, if the BBSHD had been available at the time, I would have gone for it. It is 3 lbs heavier and costs a little more, but is reported to be much more robust and tolerant to high loads.

You can see one analysis on this at What is the difference between the BBSHD and the BBS02 and is it worth the extra cost? - Electricbike.com Forum

If you haven't visited it, that Forum - Electricbike.com Forum has a lot of info about Bafang builds, tuning, troubleshooting, etc.

Faddy Daddy

Thanks for the info Dilkes, I will confess it is mighty tempting to upgrade. I was originally thinking though that I would be ok with a 500 watt and going with the 750, which Luna has on sale for 499 vs 669 for the BBSHD is a pretty decent savings. I'm also thinking of just going with a 48 volt batt as well, (such as a shark), but again, I keep reading to go 52 volts, hmmm. Looks like I'll have to do some more reading

chas58

Good questions.

Luna Cycles was started by a guy on Endless sphere, and has a very good reputation. Yeah, you can probably buy direct from China for the same price, and get no customer service and poor communication (likely because of language difficulties, and the fact you are not buying in bulk.)

The other well regarded vendor is EM3ev.
Bafang BBSHD 48V 1000W Mid Drive Kit

(I have worked with both owners of these two shops, and they are great (unlike some of the more random ebay people and other shops).

Good question about freewheeling under power. It never occurred to me you could freewheel (or backpedal) while accelerating under power with a mid drive, like you can with a hub motor.

Hub motors tend to be a little simpler in some ways, and are maintenance free. And mid drives are great to put the weight central and down low in a compact package. Certainly, changing a flat on a wheel with a hub drive can be a pain...

NoPhart

No problem. I can easily see how that would be confusing. It is what keeps me from easily mounting a front hub motor within a bikes triangle with a chain to a right crank arm mounted on the left side and keeping the standard bicycle BB assembly. In that setup you could pedal without the motor on and the hub will freewheel, but when you apply the power the standard bicycle crank has to always be turning. The BaFang worked all that out in a simple compact slide into the BB package.

As for going larger than BBS02 750W/48V, well... I don't really think you need it. The BaFang system is designed for the way it comes. Sure you can up watt/volt/amp the thing, but that's when issues arise that the average operator that isn't a builder can get into trouble with.

I can see why many people get addicted to the more powerful electric assist and even the throttle only at high levels (taking the bicycle into a whole new category of moped/motorcycle), but that doesn't sound like what your end goal is. 3lbs. is a lot of weight and if you don't need it, why add the extra weight and power? On the other hand, if you think you will gravitate to the electric motorcycle-bicycle world and don't have legal issues in your area, then go big or go home (as that crowd would say).

Honestly the 350W/37V model I have suits me fine at 6'2" 230lbs. It really is personal preference when it comes to power levels. All the modern BBS01/BBS02 are the same price, because they use the same basic components and each has to have them all, albeit slighly different in specifications.

Faddy Daddy

Thanks chas58, I wonder if any others might not know you can freewheel under power with a mid drive? I mean wow, that's a game changer in my book. Before I was pretty certain I wanted a mid drive over a hub drive but now I'm positive, no doubt what so ever.

Also thanks for the link to EM3ev, they appear to have nice prices as well, certainly a little cheaper for the BBSHD but not positive on their batteries, (haven't compared their prices on those yet), but once I pull the trigger I'm hoping to get a complete package from one vendor in case of any warranty issues. And yeah, buying directly from China is a non starter for me, at least for something this costly!

Faddy Daddy

Interesting idea on a front hub motor mounted in the triangle ... you know what you could do is get a BB set from one of the newer tandems that allow the stoker to "freewheel" (my new catchphrase, hehe). But like you said, BaFang already has it all worked out in a very nice little package.

Yeah, I'm sure once I got one I'd probably at times wished I gotten more more more - kind of like any car or motorcycle I've had but I agree, I'm thinking a 750w with a 48v batt would do quite well for me and still give me some exercise. And, it saves on the budget as well. I've never ridden and ebike but I imagine I'd be blown away (at least for the first half hour) by a 750 watt. Oh, and as you also point out I'd worry about too much power tearing up my bike components, it's a lot of money for me and I want it to last.

chas58

when comparing prices, be sure to include shipping. In many cases, that can double the price (especially with lithium batteries). It can also make returns prohibitively expensive, so make sure you know exactly what you need (with help from your friends here)

Paul, at em3ev is in China, but they have excellent customer service (unlike, BMS Battery, which has good products at great prices, but no help or instructions).
Tom, at Luna Cycles, is US based. He is going to source the stuff from China, but isn't going to mark it up as much as many of the US stores. He is an enthusiast just like the people here and is the first real alternative I have seen to buying direct from China.

They are the two stores I highly recommend.

Faddy Daddy

Well, just got back a few days ago from a nice end of summer vacation with the wife and kids, time to start moving forward with my ebike conversion.
First of all, when I started this post I was considering converting my Novara Safari but I think I've given up on that idea. For one, I love that bike, it's my do everything exercise bike and it actually makes me feel like a kid again It's a relatively aggressive geometry so does ok on the road, (I'm certainly no speed demon), but I never have any qualms about crossing a field, dirt road etc.
It's when I started trying to decide what size front sprocket to get that it really sunk in for me that it won't be the same bike anymore. It's pretty hilly where I live and I love having the 26/36/48 joined up with the 11-34 x 9 rear set, (I think that's right). It does have a pretty decent variety.
Also I would most likely have to loose the trekking bars, (simpler that way), possibly twist shifters (I've gotten used to these), and various other things. Oh, plus it has no suspension, not that that's needed of course.
Anyway, I was out in the garage and saw my wife's (seldom if ever used anymore) Specialized Crossroads deluxe and the old light bulb lit up, that would be the perfect bike for me to convert! It's a 700, has a suspension fork (likely not very great but better than nothing), a super relaxing upright position, cushy spring seat and all I can think of that I'd need to replace is the right shifter, (currently has a brake shifter combo).
It ought to make an excellent dedicated ebike, and I can even use it to tow the kid wagon.
I'm going to get the BaFang BBS02 with either a 48 or 52V battery. The one issue is it's a step through sort of frame so minimal space to mount the battery. I'm thinking of getting a rack battery from Luna cycle but dang I'm having a hard time finding an adequate rack online. One of the double deckers would be awesome but after some google searches all I could find are a few from China. Even the single level available locally seldom list the dimensions, ugh. I wonder if I could get one from a company such as Prodecotech, they don't seem to list them for sale separately on their site though. Anyone have any ideas?

dilkes

Here's a couple of double decker racks from BMS Battery (which is of course from China!)
https://bmsbattery.com/ebike-parts/6...ack&results=24

https://bmsbattery.com/ebike-parts/4...ack&results=24

Here in Toronto, I believe a couple of the ebike stores carry some as an accessory. Maybe there as well?

Faddy Daddy

Thanks dilkes, I appreciate the leads there. It looks like the first one you linked might work size wise. Luna cycle lists both their 48 and 52V rack batteries at 17"x6"x2". The top one from bms battery is 15.56"x6.02"x2.7", (or it says it is for the alloy 07 case which has those dimensions).
Unfortunately, being from China the shipping alone is $52.26, though the rack itself is cheap at $19 for a grand total of $71.26. This still isn't horrible and better than anything I can find state side .... I just hate spending that much not knowing if it will work, or if it's cheap crap, their description is lacking at best
I think before I pull the trigger I will email Luna cycle and see if they have a recommendation.
Again, thanks so much for the info!

Faddy Daddy

Well, I went ahead and emailed Luna cycle asking for a recommendation for a rack, I'm curious if they'll get back to me.
I'm also still pondering which front sprocket to get. They offer a 44, 46, 48 or 52. In their description they mention the 46 is good for off road hill climbing, the 48 middle road and the 52 for mostly flat cruising, (depending on your rear cassette of course). I'm a little thrown off by this as I typically ride mostly on my middle sprocket, a 36, and rarely go over 25mph, even downhills I more or less coast. From the Luna cycle description it makes the 44 sound like a super slow and torque laden sprocket but it's bigger than what I typically run at, huh. I don't care to go super fast, especially if I'm towing my daughter and there are some very steep hills around so maybe the 46 will do. It's just if I'm in my 48 on my safari it's lowest gear (I know your not supposed to cross the chain like that, but I had to test it, ha ha), it no where near low enough for me to climb some of the hills around here, that's what worries me. Maybe I'm underestimating the power output? But if I loose the motor or batt, I'd most likely be walking. Also some of the paths I ride on are rather narrow and twisty so I don't care to go super fast there.
So, think I'd be going wrong with the 46? (the rear cassette is 11-32 x 8), should I step down to the 44 for the steep hills towing the wagon? Or, might the 48 do it for me? (in case anyone is curious I'm around 225 lbs or so).

chas58

I have a hub motor, but I use 53 front and 17 rear, and pedal about 100rpm at 25 mph.
I also do the same with a 44t front and 14t rear. (both are about 87 gear inches)

I think the biggest problem people have with hub motors is that they bog them down. E-bike motors like to spin.

Yes, if you are pulling weight, and doing steep hills, 44 is probably best. You should have no problem doing 25mph on the flats, and climbing hills with that.
(keep in mind, there is less difference going from 44 to 46 in the front than going from 13 to 14t in the rear - its not a HUGE difference).

Faddy Daddy

Thanks for the reassurance chas58, the 44 does sound about right to me. From my normal riding I would think of even a 38 or 40 but per Luna's description they make the 44 sound like an absolute granny gear for the most extreme hill climbing!

chas58

Yeah, 44x14t puts me at 100rpm at 25mph (13t is about 90rpm) Most e-bike people are not road bike riders, and would rather pedal around 60rpm or so. For wear and tear, its best to stay around 14t or bigger in the rear (so a smaller chain ring is good for that). 11t is going to wear pretty fast and give your chain less of a bite.