DIY build prep shopping list advice

General Discussion about electric bicycles.
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casemon   10 mW

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DIY build prep shopping list advice

Post by casemon » Jul 25 2012 8:07pm

Hey all, first post, long time reader. Great site & community here! Really great to see the openness & DIY spirit alive and well! :)

Currently have a chinese ebike, and after a year, have decided to do my 1st electric conversion build! Woo hoo!

After scouring numerous online resources for a few months, would appreciate some current advice from those of you "in the know" to help me from making silly choices? Is that ok to ask here? Ebikes are fast growing & moving, and unfortunately that means there is also a lot of outdated info out there; I don't think i need to learn the hard way! haha

Myself, am technically inclined, within a diverse array of disciplines, but don't have a machine shop at the moment, so prefer something I can put together with common tools on a Saturday (as cool as those months-long DIY projects are, prefer to be up and running sooner!)

Here are my build parameters:
  • will be riding 99% in urban areas; live in a flat hot place in the US.
  • desire good-to-great speed; i know the law ;)
  • desire good distance; +25miles at very least.
  • desire having some sort of regen system, where i can just peddle and recharge the battery.
  • need some space somewhere for pannier / basket / rack; will do most of my shopping with this.
  • form & function are both important; so likely won't see any duct tape or garish wire ties, etc.
  • prefer modern & well-designed parts whenever possible (mac user here); the Cycle Analyst is very cool functionality wise, but visually is painful with that outdated dot matrix screen! :) (still will get one tho! haha)
  • have some money to spend; would rather spend $2k and build a superior machine than buying a pre-built for the same price. To say, don't mind to pay for quality goods, but prefer to not get my pants pulled down on prices, ahem.
  • am 6' 175lbs so taller bike / bigger wheels is preferred (if it helps!)
So given the above parameters, some questions, if you have answers & feel like sharing:
  1. Recommend off-hand some quality bike brands / models to use as a base? A light, but strong frame & prefer something sleek / unique that speaks to the future, but without a hefty price tag (prefer to spend the $$ on quality conversion parts!). Being able to route wiring in the frame is a big plus!
  2. Which motor would you recommend? Are eZee kits worth the price (seem underpowered). Thought maybe get eZee or Bionx; good idea? Or 9C, BMC, Crystalyte? See some geared motors at 350W but shouldn't i go with at least 500W given i desire speed? Also, prefer front motor, so i can later upgrade to a nice Rohloff! :)
  3. Battery am thinking 48v min. (for the extra push) or maybe 60v? (saw these on ebay) why so little talk of using 60v? (no motors available?) Also why do most use @10ah and so few use superior 20ah (is it the cost alone or other reasons?). Thinking LIFePo4 or LIPO (which is preferred in my case?)
  4. Any other "latest best-practices" tips or add-ons to consider? Will be getting a Cycle Analyst (is there an iPhone app yet? ;) ) Are torque arms supported / needed for front mounted motors? Etc.
Let me know if this is all too much to ask :) Just figure most of you frequent posters (you know who you are! haha) have quick-access answer to most of these questions, and it would save me headaches and mistakes.

DIY 4EVER! :)

UPDATE1: Narrowing some of this down from everyone's excellent contributions!
Have decided to go with a Cruiser base if i can find a strong one (they look cool to me haha), rear DD motor + disc brake + torque arm + CA, likely Lyen's 12FET controller, and still undecided on LiFePo4, Lipo, or the A123s (conflicting info), and balloons + seat-suspension due to lack of FS on Cruiser.
Last edited by casemon on Jul 26 2012 2:35pm, edited 2 times in total.

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fractal   1 kW

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Re: DIY build prep shopping list advice

Post by fractal » Jul 25 2012 8:56pm

welcome to the sphere! i'll be brief (its getting late) so here it goes :
1- get a mountain bike with a large triangle in the middle for the pack. you can put your pack in a back rack but they tend to break easily. i know a member who is on his third already. mountain bikes seem to be pretty good for urban riding. if you decide on a hardtail, you can use those big fat schwalbe tires to help with the cracks and potholes. a decent mountain bike only costs a couple o hundred bucks. You need good disc brakes though, trust me on that.

2-get your motor and other parts from reputable vendors. there are some respected and trusted vendors on the forum that are easy to find (i've heard a lot of bad stories about motors and batts bought off ebay). i would get something like a rear 9c. front is not a good choice in my opinion but thats me. the rear dropouts are stronger on a bike. you will also need good torque arms, they have those at ebikes.ca and methtek.com. volts = speed so 60 volts will be faster. a 9c motor can easily take 60 volts and a decent amount of current for good power. bionx is not very powerful and is really expensive.

3-48 volts is pretty decent if you dont want to go faster than 45 or 50 kph. 10ah or 20ah is just one figure, you need to think in terms of watt hours, there is a lot of info on this subject here. go to ebikes.ca and check out the simulator, its a very good tool. lipo is lightweight, compact and very dense in energy BUT unforgiving, not newb friendly and does require extra attention. lifepo4 is a bit heavier, easier to handle in terms of charging and a bit bulkier.

4-the cycle analyst is an absolute must! its an awesome tool!!! lastly, i beg you to get your stuff from reputable vendors, dont be tempted by those deals on ebay that sound too good to be true. and make sure all you components are compatible, matched and fit together.

have fun and good luck!!!
Norco A-line DH bike with :
«cromotor/hubzilla» from http://www.greyborg.com/
24s 3p Lipo (100v, 15ah)
Methods LVC/HVC cell level protection system http://www.methtek.com
24 fet infineon controller made by Lyen, heavily moded by Methods
8awg harness by Icecube57
17 inch moped rims with Michelin Gazelle tires by John Rob Holmes http://www.holmeshobbies.com
other stuff http://www.ebikes.ca

details
http://www.helicamguide.com

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casemon   10 mW

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Re: DIY build prep shopping list advice

Post by casemon » Jul 25 2012 9:21pm

Thank you for the welcome & detailed reply; will check out the simulator.

Bionx is now out of the question, for sure; seems overpriced AND underpowered (what!? haha).

Lifepo4 is probably what i'll go with, but read somewhere it is being phased out for LiNMC or something. Haven't seen a lot of sources mention this though.

Looking at other bikes more, wonder if i shouldn't go with a cruiser frame? Am not going to be off-roading, and those Fat Frank Schwalbe's sure look nice on a cruiser! Any reason not to (given my build params)?

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spinningmagnets   100 GW

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Re: DIY build prep shopping list advice

Post by spinningmagnets » Jul 25 2012 9:26pm

Plan on getting a Cycleanalyst, use it (at the minimum) to limit the amps going to the motor. Make sure the controller you get supports a plug-in Cycleanalyst so you can benefit from this feature. As soon as you get whatever motor you select, add a temp probe immediately (dirt cheap), whether you buy the screen readout sooner, or you decide wait till later to add a screen.

Your $2000 budget will certainly allow you to get a system that will satisfy you. I'd recommend using 48V, and also plan on getting at least a 15-Ah size. for 20-Ah I'd suggest two 10-Ah packs.

Flat land gives you many options. Above 30-MPH on a regular basis (48-KPH), I'd recommend a direct-drive hub. If you have a lot of starts and stops, and will stay under 30-MPH, you may like the efficiency of a geared hub like BMC or cell_man (geared are smaller, stealthier appearance, freewheel when unpowered, and lighter). Geared-hub doesn't have as much copper mass as a DD-hub, but there has been a lot of experiments recently concerning the cooling of both geared and DD-hubs.

I keep hearing good things about the 12-FET controllers. I've read that raising the amps from 20A to 25A provides a real boost during acceleration that you can feel, but going to 30A will cause a LOT of heat (watch temp probe readout).

Avoid Bionx, they have proprietary components that are hard to repair/upgrade.

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Re: DIY build prep shopping list advice

Post by mark5 » Jul 25 2012 9:43pm

casemon wrote:Looking at other bikes more, wonder if i shouldn't go with a cruiser frame? Am not going to be off-roading, and those Fat Frank Schwalbe's sure look nice on a cruiser! Any reason not to (given my build params)?
Several nice examples of others cruisers to maybe give you ideas of what you could do. A couple have front wheel motors. You can get a Hightekbikes Aotema or Yescomusa motor for the front wheel.

Beachcruzer's Stealth Cruiser
http://endless-sphere.com/forums/viewto ... =6&t=34030

nonlineartom's MAC beach cruiser, through the eyes of a n00b
http://endless-sphere.com/forums/viewto ... =6&t=33920

DervAtl's Trek Pure Comfort Bike
http://endless-sphere.com/forums/viewto ... =6&t=16240

and several more:

nonlineartom Kona Joe - the cruiser
http://endless-sphere.com/forums/viewto ... =6&t=36245

HornetB BL36 Felt cruiser
hides wiring under angled aluminum tied to downtube
http://endless-sphere.com/forums/viewto ... f=6&t=7143

Magic Pie Felt cruiser by modebikes.net
http://endless-sphere.com/forums/viewto ... 15#p540318
Last edited by mark5 on Jul 25 2012 11:24pm, edited 2 times in total.

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casemon   10 mW

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Re: DIY build prep shopping list advice

Post by casemon » Jul 25 2012 10:17pm

Those cruisers do look very nice... in fact, feel it coming together... YES, shall build a cruiser!

But not a fruity one :P Maybe with a cool matte black / bat mobile - tumbler style... yes! :)

Will likely pack the cells in the center frame (in lieu of taking over basket / rack), so will go with a central mounted secure pack or similar (good for weight distro too).

Looks like v3 Clean Analyst has option for temp sensor, cool!

Yeah, since am not getting a conversion kit, will need a good strong controller. Any brands to recommend?

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spinningmagnets   100 GW

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Re: DIY build prep shopping list advice

Post by spinningmagnets » Jul 25 2012 11:07pm

Heres the link to order a Lyen 12-FET controller ($130), lots of satisfied customers so far, many customization options. Capable of 45A continuous, at 25A it will run cool and last a long time.
http://endless-sphere.com/forums/viewto ... 31&t=17683

The $140 Thudbuster suspension seat-post can be a later upgrade, but here's my favorite cruiser style E-bike. Nicks black eTownie. The cruiser frame geometry allows you to have your feet flat on the ground when at a stop.
http://endless-sphere.com/forums/viewto ... =6&t=23701
Image

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AussieJester   100 GW

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Re: DIY build prep shopping list advice

Post by AussieJester » Jul 26 2012 12:17am

I ride a cruise style E-bike, the seating position is very comfortable, long as you have decent roads not full of potholes and patches, the lack of suspension isn't much of a concern that said, I would recommend and have myself, on my own bikes opted for font suspension....best of luck with build anyways and welcome to ES.

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dogman dan   100 GW

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Re: DIY build prep shopping list advice

Post by dogman dan » Jul 26 2012 6:39am

Am I the only one that sees a potential conflict between a low cost cruiser frame and highish speeds?

Now a good quality cruiser is a different story, or if the speeds will be not more than 30 mph. Above 30, you really do start to need disk brakes, and above 30, rims will take quite a pounding on a 25 mile ride at say 35 mph. That's when FS starts to pay for itself.

I dunno, it's the old you can have two of three things syndrome again.

Given the need for speed, hot place, and long distances to cover, I'd be saying go direct drive humbotor for sure, for the better ability to ventilate and radiate heat. 12 fet lyens controller, love mine. But depending on your definition of fast, a stock 22 amp kit controller may be all you need.

If 27 mph is enough speed, then it's pretty simple to me, Mac kit from cellman, and either 48v 20 ah A123 battery from cellman (emissions free) or 48v 15 ah pingbattery. Either battery should fit in the huge frame hole of a cruiser.

If back in stock, another option for a good but affordable motor kit is Yes Com USA, the 48v 1000w kit is known to go 30 I think.

No need to blow $$ like mad to go 25-30 mph. So that makes your budget able to do a better cruiser like a townie, instead of a huffy with crappy brakes.

If you are talking 40 mph club, then everything is going to cost a lot more, and it gets even more important to be riding a strong frame with very good brakes. To ride 40 mph for any real distance you will be looking at hubzillas, and a LOT of battery.

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hjns   100 kW

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Re: DIY build prep shopping list advice

Post by hjns » Jul 26 2012 7:21am

dogman wrote:If you are talking 40 mph club, then everything is going to cost a lot more, and it gets even more important to be riding a strong frame with very good brakes. To ride 40 mph for any real distance you will be looking at hubzillas, and a LOT of battery.
To drive home dogman's last sentence, Hubzilla at 20S lipo 74V nominal will get you to 40mph at 65Wh/mile. For a distance of 20 miles, you would need a pack of 1.3kWh. With lipo, that would weigh about 15kg / 33 pounds. Think 20S 4P.
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spinningmagnets   100 GW

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Re: DIY build prep shopping list advice

Post by spinningmagnets » Jul 26 2012 9:09am

I read a lot, but dogman has a lot of hands-on experience with a variety of kits. "real world" beats theory every time. Only thing I would like to add is, aluminum frame is OK for an unpowered pedal-bike, for an E-bike I suggest staying with a steel frame, with chromoly being the best choice. Also, don't skimp on the torque-arm. They are typically $30, an absolute must-have.

6-page "torque arm picture thread"
http://endless-sphere.com/forums/viewto ... =2&t=26444

Justins new torque arm tutotrial, from ebikes.ca
http://ebikes.ca/torque_arms/

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Re: DIY build prep shopping list advice

Post by cbr shadow » Jul 26 2012 10:22am

I'd make things easy on myself and buy everything from cellman. Tell him your needs and he'll get you there. His batteries are A123's and allow for you to plug it in and forget it. With Lipo it's not as easy. If I was in your shoes I'd get a 52v 11.5Ah triangle battery (made to fit in the triangle of a bike frame. He also sells a bag that you can put it in which has a nice clean look), Infineon controller from cellman, throttle/3spd switch, Cycle Analyst, etc.
You'll get more specific answers if you're more specific about the speeds you want to achieve, and for how long you want to go that fast.
Have fun and welcome to the board!

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casemon   10 mW

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Re: DIY build prep shopping list advice

Post by casemon » Jul 26 2012 1:47pm

@spinningmagnets
Thank you for the continued advice; excellent! And Nick's eTownie looks slick but has more of a BMX feel than a cruiser IMO; a great build just the same!

Will likely pickup Lyen's 12FET; looks like a nice bit of kit and clearly he's in touch with our values :)

And since i've resigned myself to rear-wheel motor, yes, torque arms are a must!

@AussieJester
Thank you for the welcome :)

Good advice, though the roads here are fairly new and well maintained (red state haha). Likely will go with a seat-post suspension (to help protect my bits) and with the battery pack in the middle, should have plenty of throw for any bumps.

@dogman
Great advice; indeed if going for balls-out speed on a build with no suspension, need to be prudent.

As to frame strength, which Cruiser brands are "good quality"? Looking at the spread of available cruisers, thinking maybe a Micargi, Firmstrong, Greenline or even an older Nirve. Are any of these strong (enough)? I don't know which are aluminum and which are steel or chromoly.

My build params say +25mph but if i can get closer to 40mph for marginally higher costs, I won't say no! haha. It all comes down to balance of price / value, engineering & aesthetic; example: if cannot fit all the battery for 40mph in the triangle, then i'll probably stay closer to 30mph.

As for brakes, yeah thinking disc for sure.

@hjns
Offhand, think a 1.3kWh pack fit in the mid section triangle of your average cruiser? :)

@cbr shadow
Thanks for the welcome. Cool, looks like Cellman has a lot of what i need. Though, will likely go with Lyen's custom controllers; reading his description, it just feels right :) haha

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Re: DIY build prep shopping list advice

Post by mvly » Jul 26 2012 2:01pm

Hot Area?: get a Crystalyte
Flat Area?: Get Crystalyte HS3540
Good to Great Speed?: Get Crystalyte HS3540
Peddle to Regen?: Don't do it! Use Regen to save your brakes and not to recharge battery... unless you plan to use your bike for a stationary generator. Get Lyen controller for ability to do Regen.
Going over 25miles range? You need at least 1KWh battery. Preferably a 72V battery. But seeing your budget as bing 2K, I would recommend 48V11.5Ah
Good-to-great speed?: > 25mph, 48V is ok. > 35mph, you will need at least 60V or 72V.

Here is what I recommend and hopefully it's short enough.

1) Go on craiglists and find a decent Full Suspension Mountain Bike, if you don't already have one. (~$500?)
2) Get Cellman 48V11.5Ah. Go for Cellman just for reliability. (~$700)
3) Get Lyen's 12FET controller. (~150)
4) Get throttle brakes, etc from cellman that the same time. Make sure to get CA from him too. You will need it. (~$200-$300)

This will get you started and should be pretty decent ride. As for the 25miles unassisted, you might get it with the 48V11.5Ah battery. But in my experience, you won't get it without pedal assist or going < 25mph.

Best of luck.

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casemon   10 mW

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Re: DIY build prep shopping list advice

Post by casemon » Jul 26 2012 2:12pm

@mvly
Thanks for the detailed and concise advice; lot of good info!

Funny you mention Crystalyte; got notification of your reply while on the simulator plugging in values for a Clyte i saw on eBike.ca.

Here is the output:
Image
(looks nice eh?)

(oh and a few posts down in the thread, decided to go with a cruiser base... will update the OP with latest after replying)

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dogman dan   100 GW

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Re: DIY build prep shopping list advice

Post by dogman dan » Jul 26 2012 2:21pm

Well, still harping on the bike till we sort that out.

I know squat about cruisers. Just know the $150 one won't likely have decent bakes let alone disk mount. Mine sure is a dog, with caliper brakes.

25 mph for 30 miles a day, day in, day out. Well, it was only a week or so before I ruined some wheels and went to cheapo full suspension. Big heat cracks, similar to riding across 2x4's every 20 feet on older streets. So FS all the way for me on nearly every bike I have. Even build a frankebike to have FS on a longtail.

So I really don't know what to say. When I sneak my race bike out on the street, and hit a patch or a manhole cover at 40 mph it has me shitting my pants. That's for sure. A hardtail at 40 mph will take superb streets. That bike is fine though, on beautiful race track.

40 mph is cheap. 40 mph for more than 10 miles is expensive. I lean towards saying build your cruiser, but aim for 30 mph max speed on it unless your streets really are that great. I don't believe it, when you say they are, in the USA.

30 makes it easy. Any direct drive kit and 48v battery gets you 25, 27 for most, 30 for some. It's faster on a bicycle than you think.

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casemon   10 mW

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Re: DIY build prep shopping list advice

Post by casemon » Jul 26 2012 4:40pm

@dogman
I lean towards saying build your cruiser, but aim for 30 mph max speed on it unless your streets really are that great. I don't believe it, when you say they are, in the USA.
That's very good advice; might spend more to get 40mph as you say, but won't be able to sustain it. Will aim for 30+ :)

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Re: DIY build prep shopping list advice

Post by mvly » Jul 26 2012 5:08pm

casemon wrote:@dogman
I lean towards saying build your cruiser, but aim for 30 mph max speed on it unless your streets really are that great. I don't believe it, when you say they are, in the USA.
That's very good advice; might spend more to get 40mph as you say, but won't be able to sustain it. Will aim for 30+ :)
OK here is my experience.

26 inch FS Mountain bike
HS3548 (HS3540 is similar)
74V20Ah Lipo NO BMS
CA Limited at 60A
Lyen 18FET modded for 100V. I only had it done so I can regen when my battery is full. If you get the umodded 48V-75V version, you will not regen anything > 79V
~90lbs bike so around 200lbs with me on it.

Daily Commute: 8 miles one way (16.5 miles round trip)
Average Speed: 30-35mph.
Top Speed: 44-47mph. (55mph if I am drafting a Van/Truck/Bus). There is this one section I need to go this fast to be safe.
I use average of 8-9Ah for the 16 miles ride.

Max Range test at 30mph constant on mostly flats: 38.33 miles @ 16.19Ah. Keep in mind I only charge my battery to 4.1V per cell and never discharge below 3.6V per cell.
See images below

Base on this range test, you can get an idea of what battery capacity you need. And you should know, my rig is not cheap either. The batteries and chargers are already $1300 alone. But then again I did get HK nano tech. So to get your range and sustain speed, it will cost you quite a bit. At which point, it might be better to get a lithium scooter capable of this sustained speed and range.

Hope this helps and discourages you a bit from sustaining more than 30mph. Anymore, you are really just fighting wind. Also it's dangerous for you and your motor! : )
Attachments
IMG_20120622_163049_range.jpg
Range
IMG_20120622_163050_energy.jpg
energy used
IMG_20120622_163050_energy.jpg (246.65 KiB) Viewed 557 times

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casemon   10 mW

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Re: DIY build prep shopping list advice

Post by casemon » Jul 26 2012 5:27pm

@mvly
That's a beast! I plugged your specs into the simulator and the results are insane! :)
Image

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Re: DIY build prep shopping list advice

Post by mvly » Jul 26 2012 5:36pm

casemon wrote:@mvly
That's a beast! I plugged your specs into the simulator and the results are insane! :)
Image
Actually the Simulator is not quite right. It's a bit more conservative than real life. So if it shows like 25miles range, you can probably get 27 or so. If it say 40.7mph max, you can realistically get 42mph. As for the battery capacity, you need to use 16Ah for my rig as discharging Lipo from 4.1V to 3.6V is really using only 75%-80% of the battery. For my 20Ah, this means 16Ah. Hence why I stopped at 16.19Ah. The cells were starting to get really out of balance anyways at the end of the range test.

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casemon   10 mW

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Re: DIY build prep shopping list advice

Post by casemon » Jul 26 2012 5:48pm

mvly wrote:might be better to get a lithium scooter
And am going to pretend I didn't read that :P

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casemon   10 mW

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Re: DIY build prep shopping list advice

Post by casemon » Jul 26 2012 10:39pm

@dogMan
My father (a retired NASA engineer) says that quality aluminum (like the 7005 aluminum used in Electra cruiser frames) should be more than sufficient. Is the weight gain from steel really necessary? Can go further-longer with a lighter bike...

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casemon   10 mW

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Re: DIY build prep shopping list advice

Post by casemon » Jul 26 2012 11:22pm

A quick update, likely going with either an Electra Straight 8, Firmstrong Rebel base, or Micargi Jaos 3... That cruiser-almost-chopper mix is so... Yes!

Let's see... Crupper, Crosper, no. Hmmm Cropper? :)

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Re: DIY build prep shopping list advice

Post by john7700 » Jul 27 2012 12:03am

casemon wrote:@dogMan
My father (a retired NASA engineer) says that quality aluminum (like the 7005 aluminum used in Electra cruiser frames) should be more than sufficient. Is the weight gain from steel really necessary? Can go further-longer with a lighter bike...
With all due respect to your father, dozens of engineers signed off on Sally Rides space shuttle and that thing blew all to hell didn't it. I will venture to guess your father has never built a higher powered E-bike. Many of the people here are THE cutting edge of electric bicycles and have seen a lot. Some of these guys are amazing. Hang around for a little while and I guarantee you will be amazed. I sure have been.

Aluminum is stiff but soft and that starts to create all kinds of problem after it has been used for a while. The big problems usually happens with aluminum drop outs like the one on this front fork.

Image

But what I see as a big problem and I think what dog may have been referring to is the hammering you and the bike will take on a aluminum frame in a cruiser style at high speeds. Aluminum is indeed stiff, as in has no give like a more supple steel frame and with the cruiser style, all your weight is on your arse making it much harder to shift your weight forward to ease the impacts. If you want a cruiser style bike, you should plan on cruising it. If you want a high performance bike go for a Mt. bike style and preferably full suspension.

Oh and... Weight smate, you've got a motor man. Besides we would be talking a matter of ounces here.

Just my $.02

J
Last edited by john7700 on Jul 27 2012 2:06am, edited 1 time in total.
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casemon   10 mW

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Re: DIY build prep shopping list advice

Post by casemon » Jul 27 2012 12:21am

John770, it's not a competition; I was asking about the science.

To my knowledge, none of the great people here were threatened by my statement, as a matter of purpose (am I wrong about this?)

To confirm, from your $0.02, the difference in weight between a steel cruiser and an aluminum framed one is "a matter of announces"?

And yes, the low tensile strength of aluminum is indeed a factor, very useful, thank you.

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