Custom Crank Forward for big guy

unclfuzzy

10 µW
Joined
Feb 13, 2015
Messages
5
I've been reading a lot and have gotten some really good feedback from folks at electricbikereview.com forums, but I'm still not sure what to build or get. I'm 6'2" 310# and looking for my first e-bike. Closest thing I've seen that is ready built is a Pedego Interceptor, but I really want sealed hub gears and more power for the money. I'm not actually that price sensitive, I just don't want to spend a lot of money for a bike that is a collection of compromises from my point of view. So I'll back up and try to describe what I really want and why I think I want it. This combination of things isn't available at any price on the existing e-bikes I've seen, which is why I've been thinking about buying components and building it myself.
o Internally geared hub in the rear. Needs to be more than 3-speed so I have a reasonable granny gear on the low end. Even if I wasn't looking at crank-forward frames, I'm not a stand-up-and-pedal type of guy.
o Crank-forward frame. I rode a Linear recumbent for a while but it's too long and weird. I like the idea of semi-recumbent comfort in a "normal looking" bike with standard components.
o Lots of torque and extra power that I may never need or use. This and the facts that I weigh over 300# and I want a sealed internally geared hub (see bullet 1) lead me to mid-drive, specifically Bafang 750W. And as big a battery as I can afford.
o Multiple levels of pedal assist. I intend to ride a century on this every once in a while. I want to make sure I can ride it like a real bike as long as possible and only dial in the assistance as I need it (see gears and extra power above). I want to be able to make it last all day.
Ideally I'd also like the e-kit parts to support:
o Power feeds for front and rear lights and phone. Should I get a dynamo in the front hub too?
o I don't know if I care about crank vs. torque sensors never having tried the latter, but I'll assume there's a reason to want both.
o A thumb throttle that works while in pedal-assist mode so I can goose it a little when I want. Not sure why I think I want this. At most it's a very low priority.
o Bluetooth connection to my phone with all the data I could care to consume about the system.
o Interface between the gears and motor so I don't have to think about shifting. Maybe an automatic transmission like the NuVinci with H|Sync.
Probably several other things I've forgotten or haven't thought of yet. I think I can get most of this today, with the possible exception of the last two.

Frame: sounds like I probably want to stick to steel for strength if I'm converting a regular bike to an e-bike. I could buy a RAMS crank forward aluminum frameset for $1200 if someone can come up with a convincing reason why it's worth 5x the price of an Electra Cruiser 1. The Cruiser doesn't look quite as beefy as the Townie frame, but it has the right geometry and not many extras to throw away. It's certainly cheap @ $275 MSRP. I'd love to hear other frame suggestions. I'd really like to make the limited edition Mickey Mouse Huffy work, but am not sure it's crank-forward enough even if the cheap aluminum frame would hold up.

Gearing / wheels: it seems I probably want to avoid the Shimano Nexus because V or roller brakes may not be ideal. Rohloff is almost certainly overkill for me. So, Alfine. On the fence if I'd want more than 8-speeds to sustain pedaling over 20mph. Alfine 8 apparently cruises at about 20mph in 8th gear, Alfine 11 up to 27mph in 11th. Both seem geared about the same in 1st. Probably better off getting the 11 and not using the higher gears than the 8 and wishing I had them. Looking on Amazon I can get a German-built 26" 36 spoke wheel with Alfine 11 for about $600. For another $200 I could get a matching front wheel with a Shimano dynamo hub.

E-kit: $1670 shipped for a BBS02 kit with 50V 24.8Ah battery

Other: assume another $700 or so for disc brakes, fenders, cables, kevlar tires, other random missing parts and beer.

Somewhere in the $3500 range, which is about what a new Pedego Interceptor with fenders and the 48V 15Ah battery would cost me.
 
The cruiser brake won't work with the BBS02 and the Electra Cruiser 1 has no front brake so you will need to add brakes to it.
 
Trek and Raleigh are reported to be introducing bikes with Shimano Steps mid drive plus an Alfine rear hub with electronic shifting (about $3500) be June or so (possibly later the way these new products are delayed). Doubt that the initial products will be "laid back" though.
 
OK. I like that CA-520 even better than the Electra Cruiser 1. It looks like it has a slightly more aggressive feet forward geometry and it already has gears and brakes. I can start with that and then buy a new set of wheels with the Alfine 11, dynamo, and disc brakes after I prove the concept. Looks like I need to buy a bottom bracket adapter to fit the BBS02. Anything else I would need besides the bike, the BB adapter, and a BBS02 kit with battery?

Thanks!
 
Maybe you are overthinking this?

Nice frame with two sets of v brakes minimum, ideally disc as an option too, so both kinds of mounts on the frame.

Whatever you prefer for rear gear shifting, but seriously man, you will be in your highest gear forever once you have the motor on it.

Nice powerful front hub. Cruiser bikes are great with a front hub. HT crystalyte perhaps.


http://www.ebikes.ca/shop/conversion-kits/crystalyte-front-hs-kit-advanced-pas.html

But what you really should look at is THIS. If the pedal is not forward enough for you, get a seatpost that shifts the seat back a few inches.
Possibly that would be custom made, and of course your handlebars would need to get longer so you can reach them,, like cruiser bars that sweep back.

The stokemonkey is the original and proven bad ass mid drive, for those that need cargo bike and tandem weight carried. You can run it all day at power levels that a bafang might not like.

http://www.ebikes.ca/shop/edgerunner/edgerun-stoked.html
 
CA520 came yesterday and looks pretty good. Wheels are true and no damage from shipping around the world in the flimsy box. I just had to put on the front wheel, stem, seat post and pedals and adjust the brakes and inflate the tires. Took it out for a quick spin around the block and it's definitely going to take some getting used to. The front wheel hits my toes when I turn. Probably just need to spend some time on it and figure it out. That will have to wait until it gets above 10 deg F.
 
Fix that problem by shifting your foot position on the pedals. Even on a crank forward cruiser, you pedal better with your ball of the foot on the pedal, vs the arch.

But if you prefer the arch, then just learn to stop pedaling in the corners.

Looks like that will be a great choice, no need to modify much, brakes will be fine.
 
I have read that for dual rim-brakes, the Salmon Kool-stop pads have worked quite well for many riders. I haven't had the pleasure of a test yet, but it is on my list of things to do, since I feel rear rim brakes are adequate up to the popular top-speed of 28-MPH.
 
Since it is steel though, modifying to have one rear disc brake is quite easy if you can weld. And not a huge task to hire out if you don't.

Right now my new longtail cruiser is sporting only one rear disc brake, but it only goes 22 mph.
 
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