Critique my commute bike plan, if you please.

[Rusty123]

Hello - first post here. Yes, I updated my profile to reflect location (near Seattle) :wink: Below is my background and planned build - please fire away.

Me: I'm 47 years old and 205 lbs, although fairly fit, having been bike commuting to work 2 or 3 times per week (8 miles each way) for the past several years. I'm a pretty good bike mechanic, having built a few bikes from parts, built wheels, etc. I have a background as an electronics technician (many years ago), and more recently as a civil engineer. So I'm fairly competent with mechanical and electrical stuff. Also, I favor bikes that are "clean and neat". No duct tape, floppy wires, hose clamps, etc.

My commute: Pretty flat, except for a couple 8%+ climbs on the way home (see attached commute profile). I can recharge at work. Rains a lot here, so water resistant components are important.



My bike: mid 80's vintage (brand unknown), non-suspension steel mountain bike. V brakes, 8 speed Mega-range cassette, triple chainring (48 tooth large), friction shifting. Front and rear racks, touring tires, fenders, Brooks saddle. Nothing fancy, but a solid, high quality bike that I've put thousands of miles on. See photo below. (Incidentally, I also have a long wheelbase recumbent, with a 26 inch rear wheel. It's possible that I would convert it too, but that's for another day).



My objectives: As I get older, I'm finding it more and more difficult to climb on the bike for my commute (instead of driving), particularly in the evening, when I'm facing those hills, I'm tired, and it's often dark and wet. So I'm seeking a system that will give me some assistance on my commute, particularly the hills, but not replace pedaling (since I need the exercise). I am definitely not interested in an "electric motorcycle". For those reasons, I would like to minimize freewheel drag, and since I have V brakes, also keep the weight down. 20 MPH, and enough range for my commute seems like plenty, but I can certainly envision lengthening my ride to accomplish some errands knowing that the battery can get me home faster.

My budget: $1,500.

My plan: Based on my research so far, I'm leaning towards a geared hub motor, probably rear wheel (partly so I could potentially swap it over to my recumbent someday). One of the BMC models (V4C?) seems about right. Ping LiFePO4 battery, probably 36V/20AH or 48V/15AH. Not sure about a controller yet (suggestions?). Thumb throttle, Cycle Analyst. I'm a little worried that this setup would be overkill for my objective, but I suppose it's better to miss high than low.

Any advice appreciated. Thanks!

 

[deffx]

My opinion is a Bmc/Mac motor is quite heavy and powerful and all that battery will make the bike heavy and you'll find yourself riding under power constantly even though you'll assist slightly. Not that there is anything wrong with that, it's the choice of most commuters unless they go for a 9ç DD hub, even heavier

You may want to look at a lighter motor with a better quality cst freewheel and a smaller/lighter battery to keep it a bit more bike like

Hard to explain Really

. I like the look of em3ev's new frame mount battery packs and maybe a q100cst or bpmcst would be lighter


Or the new bafang bbs02 mid drive for a clean and simple install. No wheel building, Dropout alterations, or mounting a controller somewhere as it's built in

On second thoughts I guess the BMC is perfect really just get your battery in a frame bag in the triangle or one of em3ev's frame mounted batteries

It was the the "I still want to pedal"that threw me, but hey I still work a sweat up pedaling my Mac 8t

Kudos for riding that fine looking steed though on your commute

 

[chvidgov.bc.ca]

Personally, I would go with a 48V 10Ahr Ping battery, with a smaller geared hub motor like a rear Cute 100. They are about right at 48V 15amp controller (like an ECrazyman on EBAY), surprisingly gutsy for a small freewheeling motor. And well matched to the battery. If you used say 15 watthours per mile, that should get you 30 miles no problem.

 

[Rusty123]

You're right, those q100CST and bpmcst hubs look sweet. Light is definitely better, so one of those plus a smaller battery might be more appropriate for my needs.

 

[chvidgov.bc.ca]

If you do use the Cute100 on 48V, I'd get the ECrazyman controller, rather than the KU63 or KU65 which is what is bundled with the Cuties in the bmsbattery.com kits - K63/65 are's 36V V controllers...those will hold 48V for a few months but will gradually burn out. I tried the KU93 which is rated at 48V, but at 22 amps the shunt needs to be cut (one of the shunt bridges, which gets it down to 11 amps - too much power for the Cutie otherwise. The ECrazy controller is perfect, rated at48V/ 15 amps with no shunt mods, and also runs the Cuties well - also considerably smaller than the KU93. The ECrazy is thus about 700 watts max into the Cute, which is about the upper power limit on those I think. Next step up is perhaps an EZEE kit, from ebikes.ca, but that will run you more coin...Somewhere between a BPM and Cute, closer to the BPM. The BPM is a torquey beast and way bigger/heavier than a Cute.

 

[deffx]

Yes its all a tough decision first time around, thats why most on here end up with several ebikes/rebuilds

Best to keep studying ES and find somebody elses build to replicate, or question

Probably buying a good quality and fitting battery would be my highest priority as it is the most expensive purchase, something like 48v 12Ah, i like the look of these, not that i have one

http://em3ev.com/store/index.php?route=product/product&path=35&product_id=161

Motors and controllers are a lot cheaper to chop and change down the track

 

[friendly1uk]

I don't think you need the bafang cst. I have one, using just 44v and 15 amps it is doing 27mph and 10Ah would make your round trip with perhaps 30% still left. I use the tidy little ku65 which can fit in a nice $3 frame box designed for the job. Should keep things tidy and dry. No other controller has a box to cater for it.
The ku65 is rated 36v which is a better target than my 44v as the led display has a battery meter that just says full all the time using 44v not 36. Also using 36v would trim that top speed down. It is a 4.5kg motor though. It could eat up 48v and 22amps. It is a bit big for your needs(perhaps future proof)

Back to that tidy controller and box combination, it won't hold 48v because some electrolytics in there are rated 50v instead of 63v which the pack is close to when hot off the charger. Not a big issue to swap them I'm sure. Also it is 15 amps but can be modded by thickening up the shunt with solder, to produce 18 amps. Or you can get in there with resistors and go a bit further but it will run hot.

D8veh has built quite a few bikes in this target area. Is your bike cassette based or screw on? It sounds like a good bike, and I'm thinking the 350w mxus at 36v 15amp about right. It is around 3.5kg but I advise waiting to see what D8veh thinks.

 

[d8veh]

From your requirements, a 250w geared motor would probably have enough power. A 10% grade would be easily manageable with light pedalling. A 36v 10aH battery would then be more than enough for the return trip. The one thing not mentioned so far is the speed you want to go. If you're happy with 15 mph, there's some very nice kits from Xofo and MXUS that have the plug-and-play harnesses. You won't find all their stuff on the website, and they don't make it clear that they sell single kits. The price is low and the quality is good. Xofo now do the new-style high-discharge frame-mount battery as well:
http://www.szxfmotor.com/display.asp?id=796

Both MXUS and Xofo sell a clone of the Bafang CST. I'm not sure about the MXUS one, but the Xofo does 19mph (on the road) at 36v. One of those with their 9FET controller, LCD, PAS, waterproof harness,throttle, brakes and that frame battery would be very nice kit with more than enough power for the requirements:
http://www.szxfmotor.com/display.asp?id=780
or 1Kg less is the smaller less powerful cassette motor, which i haven't tried:
http://www.szxfmotor.com/display.asp?id=783

Apart from those, there's loads of 250w kits with bottle batteries and LCDs. At 250w, a front motor would be OK.

Then, there's the Bafang BBS01 crank-drive, which is very tidy and easy to fit.

There's too much choice these days, which makes it difficult to decide.

 

[dogman dan]

Lots to agree with above. Though steep, those hills are relatively short and not that huge elevation.

Not for one used to pedaling them. I'd give different advice if you were not already quite used to spinning those feet. Somebody less athletic, I'd point to a large heavy motor, and large capacity battery. You need less raw power, and will like a quality gear motor and battery that weighs less.

Since budget is not so limited, you might look at various gearmotor kits. Lots of choices. Where you live, you should actually make a road trip in person to look at the stuff at Grin Cyclery. Ride one and see what you think, then buy this. The Ezee kit, and a 9 ah battery.

http://www.ebikes.ca/store/store_ezee.php

You will be giving your money to the best Ebike Kit vendor in the world, who pays for you to learn about ebikes on this website. Notice the lack of ads? Justin pays for that, and won't even put up an ad for his store.

But, the Ezee is not the lightest gear motor out there, so you might end up preferring the smaller motor and 48v battery approach. I point you to Grin though, because you mentioned wanting a quality setup, with no kludged together batteries and such. With a larger gearmotor, like the Ezee, you won't even notice the hills.

To keep up the exercise on an ebike, it's simple. Use only as much throttle as you need, to keep your heart rate at your desired bpm. So get the heart beating well, but at a pace you can maintain for all day. Then use whatever amount of throttle keeps you at that brisk but comfy pace, even on the steep hills. You will end up needing only about 250w of electric to go 20 mph with brisk pedaling, But wont mind having 800w on tap for those steeper hills.

 

[Rusty123]

Great replies, thanks much to all.

I've been corresponding with lectric cycles about the Bafang BBS01, which seems very well suited to my goals, for the reasons described by you all.

Lots to choose from, that's for sure!

Thanks again,

Russ

 

[dogman dan]

Whatever motor you choose, you might still want to run it on the stuff from Grin. Then you get their good controller, DP cycleanalyst, and can use the Ezee battery even if you get the whole kit elsewhere.

In any case, you want the CA, even if just the stand alone kind. I resisted this for years myself, since I was on a tight budget. Boy did I feel dumb when I finally got my first CA.

Plan on a weekend in Vancouver, seriously!

 

[deffx]

Great replies, thanks much to all.

I've been corresponding with lectric cycles about the Bafang BBS01, which seems very well suited to my goals, for the reasons described by you all.

Lots to choose from, that's for sure!

Thanks again,

Russ

If you go the bbso1 route you may wish to purchase of "Icrewes"

http://endless-sphere.com/forums/viewtopic.php?f=31&t=50188

As he is state side i believe and offers good programming, and a gaurentee

 

[Rusty123]

Whatever motor you choose, you might still want to run it on the stuff from Grin. Then you get their good controller, DP cycleanalyst, and can use the Ezee battery even if you get the whole kit elsewhere.

In any case, you want the CA, even if just the stand alone kind. I resisted this for years myself, since I was on a tight budget. Boy did I feel dumb when I finally got my first CA.

Plan on a weekend in Vancouver, seriously!

Although I've lived here for over 20 years, would you believe I've never been to Vancouver? Sounds like I finally have a reason to go

 

[Samd]

I do think a lot of the above advice may be overkill for that commute. I started the same way with a large Ezee and lipo on a similar bike, then downgraded the lot to a q100 201rpm and bottle battery with a single speed for the flat work commute. You can pick up a kit for about a third of your budget.

http://www.endless-sphere.com/forums/viewtopic.php?f=6&t=45570&p=727430&hilit=globe#p727430

Cheers.

 

[torker]

Hello welcome to ES I just skimmed and it is in the used section. http://endless-sphere.com/forums/viewtopic.php?f=9&t=56346

 

[aniken]

Although in the UK I am in a similar position and ride a winterised road race bike equipped with BBS01 having previously used a hub motor bike bought from a local dealer. Both did the 6.5 mile each way trip fine but the Bafang is streets ahead in both performance and ride satisfaction.
My hub motor bike is a mountain bike style frame not too dis-similar to your current mount but with heavy duty spoked wheels and steel tubing. With battery, motor & luggage you wont want to pedal it unpowered or with low assistance for very far unless you like the sensation of riding in Treacle! The benefit of the Bafang is that you can build it onto a lightweight bike of your choosing without having to mess about with the wheels although factor in a rear cluster/freewheel change as I found this essential to take full advantage of the added crank power. You feel like you can maximise the output & speed of the motor to both preserve battery range & best tackle undulating terrain, this is the same thing you do with your legs on a normal bike so its very symbiotic and therefore rewarding.
The hub bike is a tank and after 5000+ miles is still going strong so cant knock it, it is comfortable as hell with dynohub lights etc. huge seat, upright riding position. But I choose to forgo those comforts for the sheer speed and feeling of efficiency granted by my Bafang build. Its whatever you are into though. I was happy with my newly shop bought hub bike for 2 1/2 years before the novelty wore off and I hankered after something different. That said I still have both available to use, I built the Bafang crank drive so it accepts the same slide in lipo battery from the hub bike. I only have the one battery to worry about then and it lessened the initial build cost of the Bafang.

 

[Rusty123]

I decided to go with the BBS01. Should be here this afternoon. Looking forward to giving it a workout this weekend.

 

[d8veh]

Although in the UK I am in a similar position and ride a winterised road race bike equipped with BBS01 having previously used a hub motor bike bought from a local dealer. Both did the 6.5 mile each way trip fine but the Bafang is streets ahead in both performance and ride satisfaction.
My hub motor bike is a mountain bike style frame not too dis-similar to your current mount but with heavy duty spoked wheels and steel tubing. With battery, motor & luggage you wont want to pedal it unpowered or with low assistance for very far unless you like the sensation of riding in Treacle! The benefit of the Bafang is that you can build it onto a lightweight bike of your choosing without having to mess about with the wheels although factor in a rear cluster/freewheel change as I found this essential to take full advantage of the added crank power. You feel like you can maximise the output & speed of the motor to both preserve battery range & best tackle undulating terrain, this is the same thing you do with your legs on a normal bike so its very symbiotic and therefore rewarding.
The hub bike is a tank and after 5000+ miles is still going strong so cant knock it, it is comfortable as hell with dynohub lights etc. huge seat, upright riding position. But I choose to forgo those comforts for the sheer speed and feeling of efficiency granted by my Bafang build. Its whatever you are into though. I was happy with my newly shop bought hub bike for 2 1/2 years before the novelty wore off and I hankered after something different. That said I still have both available to use, I built the Bafang crank drive so it accepts the same slide in lipo battery from the hub bike. I only have the one battery to worry about then and it lessened the initial build cost of the Bafang.

I don't know what hub-motor you have, but I have three crank-drive bikes and four bikes with geared hub-motors. I haven't noticed any difference in riding without power between the two types. I once rode my Bafang BPM hub-motored bike 43 miles before I switched the motor on for the remaining 41 miles home.

 

[d8veh]

deleted duplicate

 

[Rusty123]

Whatever motor you choose, you might still want to run it on the stuff from Grin. Then you get their good controller, DP cycleanalyst, and can use the Ezee battery even if you get the whole kit elsewhere.
In any case, you want the CA, even if just the stand alone kind. I resisted this for years myself, since I was on a tight budget. Boy did I feel dumb when I finally got my first CA.
Plan on a weekend in Vancouver, seriously!

As mentioned in a previous post, I've ordered the BBS01, and I'm hoping it's just what I'm looking for. Time will tell.

But I must admit that I really like the Grin product line -- it's clearly very well thought out and well documented, which seems to be a rarity. Aside from the eZee motor, they also sell a very nice little kit based on a small hub motor (250W?) for $395. http://ebike.ca/store/photos/OR_StdKit.jpg

This will definately be on my short list if I decide to electrify my wife's crossover bike.