Electra Amsterdam, City Riding, New Build Suggestions Please

[Lego]

I live in San Francisco and I picked up a fresh Electra Amsterdam and I'd like to convert it to electric. I'm a newbie, yet I have 'skills' This is an ideal project for me..
Considerations
-Acceleration
I live downtown, so riding a bike in this realm is much more about getting from 0-15 fast, earning/owning the lane so that I'm not stuck riding between parked & moving cars - with the threat of getting doored. I'm thinking about a geared or a non-hub system for this reason - but I'm not sure. (Think urban taxi driver:10 or 20 seconds later, after braking for the next light or obstacle, I'll have to accelerate up to 15/20 MPH again, rinse and repeat). There is also at least a hill or two in SF, so 'low gearing' would be beneficial there too.
-Batteries
Part of the inspiration for this project is that I inherited 4 new 7.0 amp SLA batteries. I know that they are not the hottest out there, but i want to work with them (probably 3 of them) I don't need a lot of range or runtime. 7-9 miles (actual) is ok.
-Aesthetics
Clearly this bike has a flavor, and I'd like to retain it's 19th Century appearance even while grafting 21st C. technology onto it. I was thinking of attaching the SLAs along the top tube as they are black and narrow.
A front hub motor appeals to me, because i'd like to keep the 3 speed-hub pedaling functionality in the rear (and possibly brake with the front hub motor?) However a rear hub (perhaps a small diameter?) may be the most elegant and may have other benefits. Again, there is a priority on fast acceleration off the line, so if a hub design is engineered for that, then I'd go that way- despite the aesthetics

I'm overwhelmed by the choices though I've been reading about these systems for about a dozen hours. I'm hoping i can get some suggestions from y'all since there is such a great body of knowledge here.

I haven't found any Amsterdam conversions anywhere, so I'd be happy to be the first and share my progress with you in pictures, etc. THANKS!!

 

[deVries]

If you plan to ride much in damp-wet or foul weather, then I would avoid a front wheel install... doubt you could safely do torque accelerations off the line & SF has steep hills. :wink:

For lowest cost & DIY (alone no local help) go with Cellman DD or geared MAC (my preference MAC), or if you want help/advice in SF area check with ilia on ES. He has quality geared & DD motors & lots of experience doing this. You'll pay more $$, but you'll get local help, service, and advice. I'd recommend him for SF. Another nearby awesome dude on ES is Methods... he has quality DD set-ups for sale too. I think he lives near Santa Cruz? All three of these people can be found on the For Sale section of ES.

Here is ilia's website in San Francisco: http://www.ebikessf.com/

 

[Lego]

Thanks.. not too much wet weather here actually. What do you think is the bottleneck for not getting torque off the line? If it were a non-hub solution, I could see that i could possibly gear my way out of it.

 

[deVries]

Thanks.. not too much wet weather here actually. What do you think is the bottleneck for not getting torque off the line? If it were a non-hub solution, I could see that i could possibly gear my way out of it.

You seem interested in keeping a clean look w/frame. Plus, wanting to whip around w/faster acceleration rather than top speed. An eBike geared hub or DD would best be placed in the rear wheel to avoid any spinning/traction issues & allow for higher acceleration off the line.

Any mid-drive solution will be much more costly time & money wise and is not needed based on what you want to do. Get a decent DD motor & 48v or more... no prob. Geared hub will do even better for off the line & acceleration but can make more noise. Contact ilia since he sells both types of motors & demo ride to feel & hear the difference.

P.S. I hope that frame is Chrome Moly steel. I would consider bracing the rear drop-outs with longer dual torque arms. Let ilia look at it for on the spot advice.

 

[wesnewell]

Totally wrong bike and setup for what you want. Get a cheap 26" steel frame bike. put a 48V 1000W hub motor on the rear. And get some real batteries for it. That 48v 7ah sla crap won't do squat for you except add a lot of bulk and weight to take you maybe 7 miles if you're lucky. I started with the exact same ( 4 7ah sla's) and it sucked. I used them for 2 weeks only because it took a little over a week shipping time to my lipo batteries. The crappy sla's are back in the UPS's where they belong.

 

[Lego]

Thanks.. I can imagine what you mean about the SLAs - point taken. I am looking at myself, as a newbie, wasting a lot of time soft-pedaling into this project - when I should just be doing it properly from the start. What is it about this bike frame that you find inappropriate for conversion*? It's hi-ten steel, btw. I really don't want speed - there's nowhere (in terms of linear miles) to go! I live right next to Chinatown. So i thought that going with a low/moderate build geared down would do the trick. 7 lucky miles is about all i need The game is to stay ahead of slow moving cars moving at 10 mph or 15 max!! - All my regular bikes are custom geared down and i keep ahead of cars habitually.
Btw, the SLAs are inching their way towards the UPS - especially if more people agree that's where they should stay. thanks!

*for a number of reasons, too many to list - including safety/visibility of upright riding posture, I'd rather be rolling around on this than some dept store quality MTB.

 

[amberwolf]

You may want to read up on KMXTornado's build, as he is also in SF, and has posted some of his experiences with what he picked, and is thinking of upgrades now.

If you don't have the budget for better batteries, then SLA is at least usable, but I definitely recommend almost anything else, after having used various sizes myself. (and I'm on the flats, no hills, so I probably got better performance out of them than you would becuase of their weight, especially since you need quickness out of your setup, and weight works against that).

Realistically, for the lightest stuff with the best power capability, RC LiPo is likely to be your most cost-effective choice. EIG or similar, or A123 would be better especially if you could get the 20Ah pouch cells, for performance vs "safety concerns" (especially with charging) and simplicity of pack construction/wiring, but it's not cheap when you can find it, and the EIG seem near unobtainable.


One issue I can see with that is braking. AFAICS it has only a rear coaster brake. I have doubts about it's ability to stop quickly with any weight on there, from any speeds higher than maybe 10-15MPH. You might have to add at least rim brakes to the front wheel. It has no studs for modern brakes, so you might have to dig up some old calipers off a 10-speed; they would be far better than nothing.

If you use a front non-geared hub, you can also use regen braking to help slow you most of the time, from higher speeds, BUT I would not do that with the existing fork--I tried a similar fork on CrazyBike2 at one point and between the thinness of the fork legs and the tinyness of the dropouts, I could barely get the 9C motor to stay on even without regen, using old used saggy 48V 13Ah NiMH. If it werent' for the stubby torque arm and hose clamp, it probably *wouldn't* have stayed on at all, just trying to get me started rolling.

Because of that, I would also recommend a rear hub if you do use a hub, which means you'll lose any IGH that's in that wheel, making it much harder to be a pedal-bike if you have any issues with the motor at some point.


FWIW, there is a build with an older Schwinn bike of similar basic frame design, using a homemade middrive, SLA in rear bags, etc., if you want to read up on how such a frame takes weight and torque and such. I can't remember the name of the poster or bike, but I do recall it was a brown bike. :? Probably been 2-3 months since the last post in that thread that I recall.

 

[Lego]

Awesome advice. Thanks for the referral. And great insight on the braking issue. Yes .. I bought some calipers - and the arms were too short, so I'll go fish again.
I am understanding the desirability of rear drive - but I'll lose the IGH, which does not appeal to me. So the decision is still open.
I suppose if i went with the rear drive -and i desired NOT using a standard multi-gear cassette (included on these kits?), I'd have to do a single gear conversion?
I also pondered the approach of mounting a Blackburn MTF-1 front rack - to hold the batteries, but now I'm considering fork stresses.
I'm also learning that DD motors can be specified for speed or torque.

 

[dogman dan]

You are now pretty much stuck with a front hub. (unless you went non hub) A "regular direct drive front hub kit" will actually accelerate off the line pretty good compared to pedal starts you are used to. But a larger gearmotor would be a tad faster off the line, if you don't buy the fastest winding. I'd avoid the tiny gearmotors. Not enough watts for SF with those.

I'd say 8 t Mac from cellman would be good, run on 48v. Or maybe the 10t since you will have some steeper hills. Traction will only be a problem on the steepest hills when it's wet. Sure, the tire will scratch some as you start, but it's no big deal except for tire wear.

Definitely need a torque arm. Definitely lose the lead as soon as you can afford to.

 

[nicobie]

It's your choice of bike that is causing all the problems. Any chance of returning it for another model?

Check out my Electra in the link in my sig.

 

[dogman dan]

I don't particularly see front hub on dry street as a problem. He's not building a trail bike for mountains and singletracks.

Mostly, he just needs to not make the mistake of thinking 350 watts will get him up San Francisco hills.

 

[Drunkskunk]

I think the MAC motor is about the only real choice you'll have for SF hills, for a hub motor.

That bike is nice, but with its 120mm rear dropout, rear only brakes, and pencle thin front fork with no brake bosses, its not a good bike to convert.

You can convert that bike to have brakes by replacing the front fork and adding the brake handles, cables, ect, but it will cost you more than another bike.

You might check Craigslist for a good used bike to convert, and keep the one you have for pedaling

 

[deVries]

Your bike is well suited for a Kepler or Adrian Friction Drive 'FD' to the rear AND you can keep your IGH. You say you don't want to ride fast... the catch with these FD setups is you need to pedal a few mph before starting the FD motor. Won't work well or at all in wet conditions because of slippage, but you indicated not needing a wet weather requirement.

This setup is super light weight - perfect for less than 10 mile range - and you can remove it easily for theft issues - it is very stealth too!

EVTodd did his own FD too... it is awesome! It can be driven off the line with no pedaling... but it is totally DIY & learning on the forum.

See For Sale section for Kepler & Adrian Friction drive... both well tested... excellent guys to work with too! 8)

Dude, it's friction drive for you with this bike... otherwise, change the front fork with a strong steel fork w/disc brake mount & put on a high torque geared motor... See ilia please in SF... the dude lives there AND will help you... spend the money or do the time learning on ES for DIY.

Man, go with ilia who lives where you do!!! ilia: http://endless-sphere.com/forums/viewtopic.php?f=31&t=11024&hilit=ilia

Adrian: http://endless-sphere.com/forums/viewtopic.php?f=31&t=34586&hilit=adrian#p502695

Cellman for MAC motor on front fork & DIY: http://endless-sphere.com/forums/viewtopic.php?f=31&t=17029&hilit=cellman
He sells a 350w motor... get high torque... and volt ONLY to 36v... and use TWO torque arms... and MAYBE you can keep your Front Fork you have now since it is steel... IF it fails at least will not not likely snap off... Installed with long dual torque arms & it should work. Check with Dogman about the dual long torque arms. If you have a rim brake hole on your frame at fork crown, then put on a front rim brake at least. If you replace the F-fork, then you can get a disk brake mount on the FF & MAC motor... go steel or CrMo steel.

Just search on Kepler Friction Drive to find him too...

And, hell no to SLA.

Best of luck...