The "Bonanza Bulldozer" Dual PhaseRunner 2WD eMTB

General Discussion about electric bicycles.
Post Reply
User avatar
Alan B
100 GW
100 GW
Posts: 7025
Joined: Sep 11, 2010 7:43 am
Location: San Francisco Bay Area, USA
Contact:

The "Bonanza Bulldozer" Dual PhaseRunner 2WD eMTB

Post by Alan B » Sep 12, 2010 9:47 am

REI Novara Bonanza Aluminum Mountain Bike Before

Image

In Progress (working but not completed)

Image

This Bike's Photo Album

https://picasaweb.google.com/1158081452 ... directlink

Details

https://docs.google.com/spreadsheet/pub ... utput=html

How we got here:

Every year or so I get interested in assembling an e-bike for my commute. But with a 13 mile each way route with lots of climbing it has never appeared to be practical. However that seems to be changed now due to better batteries (lithium), controllers (FETs) and motors (magnets). So now I'm contemplating it again and have read a couple thousand posts on here in the last few days (thanks for all the info!).

I'm a Software and Electronics Engineer who used to ride motorcycles and recently designed and built a microprocessor based high power (15A 60V) flashlight controller using A123 and LiMn cells, so the technology in this project is somewhat familiar, but this is my first e-bike.

So I would love to get some comments on the practicality and specifics of doing this project.

On to a few details. I have a pristine aluminum mountain bike that is a few years old from REI (found the receipt, it is a 2000 Bonanza AL, and I estimate it has less than 50 miles on it - I didn't ride it much). It has aluminum forks with Zokes front suspension, SRAM 5.0 9 gear rear cluster and twist grip SRAM 7.0 shifting. It has V brakes but it looks like there are mounts for a disc on the front forks but not the wheel. No apparent disc brake mounting holes on the rear frame.

I found the Bike's specs online here: http://www.rei.com/product/646002 (no longer valid)

I don't have a lot of free time so will probably not build much to start with but use good quality existing modules and kit parts. Though I do like Anderson Powerpoles a lot more than some of the other connectors out there and I have the crimper.

I would like to commute to work via e-bike a couple days per week, weather permitting. But here in this part of California the weather is pretty good a lot of the time.

It would seem to me that with my hilly route (about 1500 feet of climb in 13 miles up to an almost 15% grade, rough pavement, lots of curves (25 mile speed limit for almost half the ride), desire to get some exercise but not be a sweaty mess when arriving at work, being out of shape, and desire to be able to go 20 mph or so over most of the trip that I should probably:
  • use a rear geared hub motor perhaps 500W (something that climbs well)
  • which would require that I convert shifting to 6 speed rear (to have room for motor)
  • use a thumb throttle to clear the twist shifter (but would prefer half-twist throttle and change the shifters)
  • use new brake levers with cutout switches (separate control for regen?)
  • use a paralleled pair of 36V 10AH LiFePO4 batteries for balance and flexibility and 20AH on board (not planning to use 72V but that would be an option)
  • have a charger at work and at home (might need two at each place)
  • convert to disc brakes (in front at least) (may not be practical in rear)
I look forward to your comments on my project plans. Suggestions for specific motors, controllers, kits, etc would be appreciated.

Thanks in advance,

Table of Contents
  • First Test Run (Rear Wheel Drive) page 6
  • System Weight 63 lb page 13
  • Marin stress test ride, First Commute run page 18
  • 2WD Upgrade planning begins page 21
  • 2WD goals, fork selection page 22
  • Throttle Manager, changing to PhaseRunners page 23
  • New Shifters, PhaseRunner RWD Testing page 24
  • 2WD First Run, Configuration Summary page 25
Last edited by Alan B on Sep 11, 2016 6:02 pm, edited 64 times in total.

RICK
10 mW
10 mW
Posts: 30
Joined: May 02, 2010 6:35 pm
Location: eastern ma

Re: Planning a Commuter build

Post by RICK » Sep 12, 2010 10:44 am

My only experience is one year with a plain vanilla 9C 2807 run with a 48V Ping. The motor has been on 2 bikes, a older Schwinn Passage and Kona Worldbike. I have about 1600 miles this year on the motor. Used on a 16 mi commute for exercising my nearly 50 yo carcass.

Some thoughts:
Power - To climb 1000 ft you'll want power, and 500W will be marginal. This leaves dragging more power out of a gearmotor (recipe for breakage it seems) or a larger DD. I can say that its a rare hill that slows me to less than 20 mph, though it really depends how steep. Maybe one of the slower winds on a DD? Consider regen, it might be useful for your route.
Battery - A 15 AH Ping is good long term for a 20-25 A discharge. If you need more power you'll need a bigger battery, very likely with your route I think. I'm presently using 7-9 AH on my 16 mi, moderately hilly route cruising at 26-28 mph.
General ruggedness of build - Going fast on rough roads with a big battery is really tough on your bike. Get a good rack (maybe steel). Keep an eye on any aluminum pieces holding up the battery (I ended up fabing some steel brackets). Check your spoke tension and hub nuts, particularly as you're just starting out. Torque arms. Consider getting the motor laced into a high quality rim (John Rob Holmes).
Safety - Get good lights and a large mirror.
Comfort - I ended up getting a fancy Thudbuster suspension seat post, as my back could not take the pounding. It works very well.
Cost - You'll spend something like $1000-$1500 (minus the bike itself), and may end up just starting over at some point. Think of it as a hobby with good health benefits and reduced gas usage to defray some of the cost.
Vendors - Going with known, trusted vendors is definitely worth it. My experience with ebike.ca (aka Grin), Ebike.kit, John Holmes, Ping, has been very good. There are many others spoken of highly in these forums.
rick

front 9c,48v ping, plain vanilla commuter

User avatar
dogman dan
100 GW
100 GW
Posts: 34315
Joined: May 17, 2008 12:53 pm
Location: Las Cruces New Mexico USA

Re: Planning a Commuter build

Post by dogman dan » Sep 12, 2010 12:50 pm

That's exactly what you want. Get the E-Bikekit 9c motor and pair it up with a 48v 15 ah pingbattery, or go for the even lighter lipo. Very nice, 48v gets up the hills just a bit better, and if you need speed at times, you get 27 mph. Peak watts with a 48v battery is 1200 watts. And you want a cycleanalyst.

It works good for me, I climb 1000' of vertical over 14.5 miles to get home everyday. It'll do it even if the temp is 105 F without frying. With some brisk pedaling, grades up to 10% are no problem, and 7% grades won't even require pedaling, even if they are for a mile or two. Here's my review of the motor, which I now run at either 36v or 48v. https://endless-sphere.com/forums/viewto ... 58&start=0

User avatar
Alan B
100 GW
100 GW
Posts: 7025
Joined: Sep 11, 2010 7:43 am
Location: San Francisco Bay Area, USA
Contact:

Re: Planning a Commuter build

Post by Alan B » Sep 12, 2010 4:05 pm

Thanks for the suggestions. 48V does sound interesting.

Not sure I can use a front hubmotor. I believe the front suspension forks are aluminum. Zokes System Z Port. Novara Bonanza AL frame.
Last edited by Alan B on Mar 13, 2011 7:41 am, edited 1 time in total.

User avatar
dogman dan
100 GW
100 GW
Posts: 34315
Joined: May 17, 2008 12:53 pm
Location: Las Cruces New Mexico USA

Re: Planning a Commuter build

Post by dogman dan » Sep 12, 2010 5:04 pm

Yeah, I have alloy forks on my commuter, and installing a frontie on them was not for a first timer.

They have rear hubs on the websites for sale, At E-bikekit, or Ebikes-ca . The 9c motor is a solid motor for a commuter or even cross continent bike. It's doesn't freewheel like the gearmotors so real pedalers don't like that as much. But a 1200 watt 9c outclimbs the crap out of a 400 watt gearmotor. The freewheel in a gearmotor is not really needed, with a DD motor it only takes a tiny tiny bit of throttle to make the motor drag go away. This uses almost no power if you want to pedal a lot to extend your range.

You may have to get a 7 speed shifter and rear derailur on ebay to use the rear hub, that usually comes with a 7 speed cluster. Yours will use skinnier chain so I doubt they will be compatible. It's ok though, you'll only use 2-3 gears once motorized.

User avatar
Alan B
100 GW
100 GW
Posts: 7025
Joined: Sep 11, 2010 7:43 am
Location: San Francisco Bay Area, USA
Contact:

Re: Planning a Commuter build

Post by Alan B » Sep 12, 2010 5:50 pm

Thanks for the info.

Disappointing that the various solutions are so incompatible with my existing MTB. I only found one rear gear motor that will work with a 9 gear cluster. Don't really want to get into changing either forks or transmission. This bike is essentially new it has had so little use.

The pavement on these roads is pretty rough in spots, really should have a front suspension. And probably a seat suspension as was mentioned.

edit - I did get a 6 gear cluster and shifter and am still using the original skinny chain which seems to work ok.
Last edited by Alan B on Nov 05, 2012 1:08 am, edited 2 times in total.

User avatar
Alan B
100 GW
100 GW
Posts: 7025
Joined: Sep 11, 2010 7:43 am
Location: San Francisco Bay Area, USA
Contact:

Re: Planning a Commuter build

Post by Alan B » Sep 12, 2010 7:42 pm

Perhaps I should consider replacing the front fork. What would be a decent cro-moly front fork with suspension for a front motor, or can a front suspension be used with a motor at all?

User avatar
Ykick
100 GW
100 GW
Posts: 5944
Joined: Nov 26, 2009 6:10 pm
Location: San Diego, California

Re: Planning a Commuter build

Post by Ykick » Sep 12, 2010 8:17 pm

Alan B wrote:Perhaps I should consider replacing the front fork. What would be a decent cro-moly front fork with suspension for a front motor, or can a front suspension be used with a motor at all?
Here's my commuter. Cheap, steel bike and steel suspension fork.
ride2.jpg
Fork is pathetic with regard to dampening/rebound control but at least it springs which does help on rough road. If I had it to do again I would try a rear motor. The front is pretty good and simpler to install (with proper forks) but it can struggle for traction on some surfaces. If that happened during a turn might wash out?

I finally got rid of all my derailers. I'd like to have a 50-52T front or perhaps 11T rear. 48T/13T current gearing is slightly low for my general cruising speed.
Talent must not be wasted.... Those who have talent must hug it, embrace it, nurture it and share it lest it be taken away from you as fast as it was loaned to you.

- Frank Sinatra

999zip999
100 GW
100 GW
Posts: 8142
Joined: Jan 10, 2010 1:40 pm
Location: Dana Point So. Cal

Re: Planning a Commuter build

Post by 999zip999 » Sep 13, 2010 12:37 am

I would save the alumiun bike and buy a used steal frame 7 speed front sup. rear drive motor. If you need to mod. the frame for a 48t front you can mod. a steel bike with a hammer. Plus they have good comp. 70-120.00usd. total and a seat gel up enough for a wife. I like 48v but two 36v sounds like more fun 72v no never.

User avatar
dogman dan
100 GW
100 GW
Posts: 34315
Joined: May 17, 2008 12:53 pm
Location: Las Cruces New Mexico USA

Re: Planning a Commuter build

Post by dogman dan » Sep 13, 2010 5:13 am

Yeah often it's just plain easier, especially with a first bike, to go for something steel, or at least steel in the dropouts. My first commuter was a cheap wall mart mongoose. Just like in the pic above. Crappy suspension, but good enough for street, and steel suspension forks. The rear swing arm on those bikes is steel too. An upgrade from those bikes is the mongoose blackcomb. You can get those at walmart online, and they ship. Big fat beautiful rear steel dropouts on that one.

But a just as good, if not better approach is to find something used, in a bottom of the line bike like a Trek 820. It's a decent entry level bike, with steel frame. It has steel forks too if you want front hub. To use motors on suspension forks you have to do some measuring to be sure the motor will clear the tubes when installed. On the really cheap steel forks, you can squash em a bit to get a few more mm of space. Modify with a hammer literaly.

User avatar
Alan B
100 GW
100 GW
Posts: 7025
Joined: Sep 11, 2010 7:43 am
Location: San Francisco Bay Area, USA
Contact:

Re: Planning a Commuter build

Post by Alan B » Sep 13, 2010 6:43 am

Thanks for the suggestions.

I really like the idea of the cycle analyst and the ability to use it to limit torque and speed. This can be important to keep the system safer to operate especially when starting out, or letting a friend try it.

Did a bunch more research and reading, as well as some thinking about front motors. Since the front forks are not designed for those forces, especially when they are suspension type, I think I will not consider front motors further. The rear forks are designed for these load vectors. Rear motors are more motorcycle like and may be safer and more 'normal', at least for my past experience.

It is unfortunate that the particular transmission on this bike is 9 rear gears as this is not very compatible with rear motors. 6 or 7 would be better.

I'm concerned about the ergonomics of the thumb throttle. I have thumb throttles on my ATVs and it is not the best situation. This will be used a lot more than they are, and I don't need ergo problems as that interferes with my work. A half twist throttle seems to me a better choice. Again we have a conflict with the Sram 5.0 transmission system's shifter.

So again it looks like the transmission needs to be changed.

Starting with another bike is not too appealing. I already have a storage problem and cannot just add more bikes.

Perhaps I need to look further at changing out the whole transmission system. Go to 7 gears.

I would like to be able to ride this off-road occasionally though that will be rare. And I don't want to lose the ability to ride it home if the batteries or some other system failures occur. So I probably do need 2-3 front chainrings for occasional use and backup.

User avatar
GCinDC
10 GW
10 GW
Posts: 4317
Joined: Jan 23, 2009 11:19 am
Location: Washington, DC

Re: Planning a Commuter build

Post by GCinDC » Sep 13, 2010 8:02 am

for an expensive but elegant, lightweight and well designed (but closed) system, consider the BionX 500.

sounds like you're a tinkerer tho... :D

you might research the geared motors too, like BMC.
Youtube channel, 2013 Highlights vid. Ebike Nerdcast.
Giant DH Comp: 20s lipo (11.6Ah), hs3540, Adaptto Mini-E, 900W BMSBattery charger.
GT I-Drive (sold), 20s lipo, 9C, 72V 45A 12FET.

User avatar
Alan B
100 GW
100 GW
Posts: 7025
Joined: Sep 11, 2010 7:43 am
Location: San Francisco Bay Area, USA
Contact:

Re: Planning a Commuter build

Post by Alan B » Sep 14, 2010 1:12 pm

Thanks for the suggestion of the BionX. I have looked at them and they appear to be quite interesting but I have more interest in something that I can, as you say, tinker with. I may need a lot more battery for my commute, and I may want more peak power. I also like the ability to buy parts and not have to spend the whole cost at once, it fits the budget better.

If I use a 9C rear hubmotor on my aluminum frame mountain bike I will need to make changes to the gearing. It currently has SRAM 5.0 3x9 twist shifters. The hubmotor can be obtained with a 6 gear freewheel, so I need to set up for that instead of the existing 9 speed.

So what will I need to change:

Rear Derailleur, shifter and cables (probably)
Front Derailleur, shifter and cables (maybe)
Chain (?)
Chainrings (??)

I prefer to use a half-twist throttle so some other type of handlebar mounted shifter would be good.

I plan to use some of the new brake levers with switches for cutout/regen. So the shifters need to be compatible.

How can I identify the correct new parts for compatibility with the 6 speed freewheel on the 9c motor? Any suggestions for brands, models that are compatible would be appreciated.

Thanks in advance,

User avatar
GCinDC
10 GW
10 GW
Posts: 4317
Joined: Jan 23, 2009 11:19 am
Location: Washington, DC

Re: Planning a Commuter build

Post by GCinDC » Sep 14, 2010 1:59 pm

As for the gears, I effectively have two, controlled only by the front derailleur, and i only use the low one if i run out of juice!

But this all depends on your speeds. So how fast do you plan to go?

With a 9C and a lot of battery, you won't need the low gears as much.

I strongly recommend getting this 7sp 11T rear freewheel that fits the 9C: http://www.cycle9.com/c9store/electric- ... 1-32-p-136

A lot of freewheels don't fit properly on the hub motors. This one does. And as far as I know, there's no way to get an 11T w/o the other six gears. My rear derailleur has been deactivated. I only keep it w/ a much shortened chain as a tensioner.

I'd LOVE to have a bigger front sprocket, like 56T, but this requires machining, bottom bracket non-sense, etc.

So again, how fast do you want to go? How far between charges? And what terrain?
Youtube channel, 2013 Highlights vid. Ebike Nerdcast.
Giant DH Comp: 20s lipo (11.6Ah), hs3540, Adaptto Mini-E, 900W BMSBattery charger.
GT I-Drive (sold), 20s lipo, 9C, 72V 45A 12FET.

montyp
100 W
100 W
Posts: 112
Joined: Sep 14, 2010 1:41 pm
Location: Minneapolis

Re: Planning a Commuter build

Post by montyp » Sep 14, 2010 2:04 pm

You can just put a single speed freewheel on the rear motorhub. You can put a 9-speed chain on single speed freewheel <- a local bike shop could tell you for sure. The bike would end up being three-speed, cause I assume you have a three speeds on the front derailer.

Your going to want to put the rear derailer into the gear position that matches up with the single-speed. Take it off the handle bar shifter and tie it to the frame. Now you can use a motorcycle-style throttle.

This is this the setup I run on my bike, only cause I'm cheap and had a single speed freewheel sitting around. You can get a single speed free wheel for $15-20 online.

Good luck!

p.s. the other nice thing about this setup is that if you don't want to use the motorized hub, you can just put your original wheel back. If you change your gear setup, that 9-speed rear wheel is going to be worthless to you.
+10K miles, rides through whatever Minnesota weather can dish out.
Software engineers don't have to worry about ESD, we are software engineers because we have no potential.

User avatar
dogman dan
100 GW
100 GW
Posts: 34315
Joined: May 17, 2008 12:53 pm
Location: Las Cruces New Mexico USA

Re: Planning a Commuter build

Post by dogman dan » Sep 14, 2010 2:58 pm

On my first commuter the bike frame had the space to put on a big front chainring. I found a 56t on ebay, and luckily I had a crank it would fit on in my pile of bike parts. It won't fit on my current commuter though, so it's on the race bike now.

The big ring make a regular derailur awkward if not impossible, so it got tossed. At a stop, I could still use fingers to put the chain on a smaller ring when needed, rarely. That left the left handlebar bare, so the twist shifter got moved over there, and mounted upside down. Worked fine. You can find the 7 speed derailur and shifter easily and cheaply on ebay. Rear motors are often sold with a freewheel, or you can get one from the motor supplier that fits.

Tom Tom
100 W
100 W
Posts: 193
Joined: Oct 28, 2008 12:55 pm
Location: Colorado Springs

Re: Planning a Commuter build

Post by Tom Tom » Sep 14, 2010 3:38 pm

I'm thinking of a similar setup myself, leaning towards 9c rear, 66volt lipo, lyen controller.

But, I would love to find a 6x10 9c motor as Dogman's reviews(and others) indicate that it
climbs better than the more commonly available 9x7.

Anyone know of any available 6x10 rear 9c hubmotors in the United States?

User avatar
GCinDC
10 GW
10 GW
Posts: 4317
Joined: Jan 23, 2009 11:19 am
Location: Washington, DC

Re: Planning a Commuter build

Post by GCinDC » Sep 14, 2010 3:56 pm

Does the 6x10 climb better? I didn't notice that when I installed mine (got on sale via ebikekit). I did notice that it was like 10 mph slower tho! Seriously...
Youtube channel, 2013 Highlights vid. Ebike Nerdcast.
Giant DH Comp: 20s lipo (11.6Ah), hs3540, Adaptto Mini-E, 900W BMSBattery charger.
GT I-Drive (sold), 20s lipo, 9C, 72V 45A 12FET.

User avatar
Alan B
100 GW
100 GW
Posts: 7025
Joined: Sep 11, 2010 7:43 am
Location: San Francisco Bay Area, USA
Contact:

Re: Planning a Commuter build

Post by Alan B » Sep 14, 2010 9:51 pm

Climbing is important to this build as there is a lot of up and down on my commute route. Today I measured the grade at one end which I suspect is the steepest spot, and it is just under 10%.

So I need to understand the system velocity at 10%.

User avatar
amberwolf
100 GW
100 GW
Posts: 23948
Joined: Aug 17, 2009 6:43 am
Location: Phoenix, AZ, USA, Earth, Sol, Local Bubble, Orion Arm, Milky Way, Local Group
Contact:

Re: Planning a Commuter build

Post by amberwolf » Sep 14, 2010 10:39 pm

Regarding the transmission changes:

--use a trigger-shifter (brake-shifter combo) if you want easy access to the gear changes without moving your hand off the bars.

--use a thumb shifter (indexed) if you don't mind probably moving your hand off the bars or at least over a little while shifting, as it possibly won't quite reach over the throttle and brake mounts to be easy enough to reach.

--use a thumb shifter attached to a bar-end mounted inboard of teh brake and throttle, so that the thumbshifter hangs over your throttle or brake fingers for easy access. May require a very short bar-end with a long parallel.

--Move the righthand (rear) shifter over to the left, if you don't use the front rings' shifter much. Keep both over there but move the front shifter inboard of the rear, so you can stll use it if you have to.

--Use any shifter you like for the rear, on either side of the bars, but only use the front ring shifter (on the left) for the most part (unlike how most of us learned). You may not need much more than this for most of your ride, once you set the rear shifter in a compromise position that works best for most situations. You get about two rear gearshifts for every front gearshift, so it's like having the spread of 6 gear changes but with only 3 actual shifts between them. Can work pretty well.

toaroa
100 mW
100 mW
Posts: 39
Joined: Jun 09, 2010 8:33 pm

Re: Planning a Commuter build

Post by toaroa » Sep 15, 2010 3:00 am

I've noticed that majority advice here to those starting out is avoid front hub if you have alloy suspension forks. It's not particularly expensive to buy some surly instigators or kona p2s, resulting in really good steel upon which to mount your front hub. Where I live (New Zealand), people are still throwing away good steel forks on our equivalent of ebay in favour of suspension, and as long as you're careful that the steerer is longer than you need, they're easy to fit or cheap to have fitted. Of course, riding without suspension will not appeal to everybody, but for a commuting bike there are efficiency advantages and I regularly ride my aluminium frame/surly instigator-forked MTB on gravel roads without problems.

=> not necessarily a better way to do it; just another way which was its own combination of advantages and disadvantages

User avatar
dogman dan
100 GW
100 GW
Posts: 34315
Joined: May 17, 2008 12:53 pm
Location: Las Cruces New Mexico USA

Re: Planning a Commuter build

Post by dogman dan » Sep 15, 2010 6:06 am

I defined 6x10 climbing better as climbing cooler. On really steep single track trails, 15-20% grades, I can lug along with the 6x10 at 10 mph without as much heating as you'd get if you tried to climb a 9x7 that slow. So for me that's climbing better. The 6x10 is very very comfy on a 10% grade while the 9x7 is pretty much maxed out at 10%.

But I never said a 9x7 sucked as a climber. "normal" roads in the US rarely exceed 7% grades. Some residential streets and driveways may be lots steeper, but highway type roads keep it under 10% almost always. So give a 9x7 20-30 amps of 48v nominal voltage and they will zip right up it no problems. In my tests with a stock 20 amp controller and 3 miles of 5-7 % grades on San Augustine pass, no pedaling at all is needed to cruise up that hill at 15 mph.

If I knew of a 6x10 rear for sale, I'd be bidding on it. Hopefully they will come back. Perfect for the dirtbikes and cargo bikes at 48v.

Just get a 9x7 for now. If you need more hill climbing power, put 72v into it. With brisk pedaling, I can maintain 15 mph up 10% grades with 48v. See this thread.
https://endless-sphere.com/forums/viewto ... =3&t=17412

User avatar
GCinDC
10 GW
10 GW
Posts: 4317
Joined: Jan 23, 2009 11:19 am
Location: Washington, DC

Re: Planning a Commuter build

Post by GCinDC » Sep 15, 2010 7:25 am

That's interesting, Dogman. I hadn't noticed that. I HAD noticed that the 6x10 used very little juice. Up a steady, say 7% grade, my 9x7 would be sucking 45A, and getting dangerously hot, whereas on the same hill, the 6x10 trucked on up, pulling 15-20A. And I noticed on my daily start and stop commute with the 9x7, I'd use 4Ah, the 6x10 would barely draw 2Ah!

For speed on the flats, my vague recollection is:
9x7 @ 80V = 40mph
6x10 @ 100V = 33 mph

Alan (and others) you might enjoy playing with some simulators to get a sense of different motors/voltages, etc:

https://endless-sphere.com/forums/vi ... 97#p287797

http://www.ebikes.ca/simulator/

Also, some other misc points:
- the 11T cog on the freewheel does a lot to compensate for the gearing adjustment w/ a motor, and is much easier than dealing w/ changing the front chainring
- easy to get good torque arms for a front motor install, but not for rear. and if you're going to use regen with any power, you might need 4 custom jobs. but these will compensate for having aluminum dropouts. (i MUCH prefer rear motor to front). ps. does ampedbikes have universals which work well w/ rears?
- other points i forgot :lol:

let's have a photo of your bike! i'm wondering if you'll put the battery in the frame or on a rack...
Youtube channel, 2013 Highlights vid. Ebike Nerdcast.
Giant DH Comp: 20s lipo (11.6Ah), hs3540, Adaptto Mini-E, 900W BMSBattery charger.
GT I-Drive (sold), 20s lipo, 9C, 72V 45A 12FET.

Tom Tom
100 W
100 W
Posts: 193
Joined: Oct 28, 2008 12:55 pm
Location: Colorado Springs

Re: Planning a Commuter build

Post by Tom Tom » Sep 15, 2010 8:23 am

Thanks for the info guys. I'm a noob, so feel free to teach me the ropes.

Another question. How much "better" could a 9x7 climb if installed in a 20" wheel?

Could a slope of say around 15% be conquered?

User avatar
Alan B
100 GW
100 GW
Posts: 7025
Joined: Sep 11, 2010 7:43 am
Location: San Francisco Bay Area, USA
Contact:

Re: Planning a Commuter build

Post by Alan B » Sep 15, 2010 8:44 am

amberwolf wrote:Regarding the transmission changes:

--use a trigger-shifter (brake-shifter combo) if you want easy access to the gear changes without moving your hand off the bars.

--use a thumb shifter (indexed) if you don't mind probably moving your hand off the bars or at least over a little while shifting, as it possibly won't quite reach over the throttle and brake mounts to be easy enough to reach.

--use a thumb shifter attached to a bar-end mounted inboard of teh brake and throttle, so that the thumbshifter hangs over your throttle or brake fingers for easy access. May require a very short bar-end with a long parallel.

--Move the righthand (rear) shifter over to the left, if you don't use the front rings' shifter much. Keep both over there but move the front shifter inboard of the rear, so you can stll use it if you have to.

--Use any shifter you like for the rear, on either side of the bars, but only use the front ring shifter (on the left) for the most part (unlike how most of us learned). You may not need much more than this for most of your ride, once you set the rear shifter in a compromise position that works best for most situations. You get about two rear gearshifts for every front gearshift, so it's like having the spread of 6 gear changes but with only 3 actual shifts between them. Can work pretty well.
This is a bit hard to follow completely (haven't looked at a bar-end yet), but there is some good info there. I was wondering if dual handlebars or some type of extensions might help out with the controls (but moving around is not all that appealing). If I go for combo shifters / brakes I lose the switches (unless they can be retro-fitted), but that's probably okay. I don't need the switches to disable the controller as I'm used to motorcycles where you have to let go the throttle when you brake. I do need something to control regen but ideally that would be a different control anyway. Actually a trigger or thumb on the left side would control regen. Proportional control of regen would be great. Especially on my 9% grade. Left hand thumb control would be best since the fingers could be on the brake lever while the thumb feathered the regen so I could move smoothly from regen to braking. Then a combination could be used which would be useful as I need to turn off that steep hill midway onto a steep downhill driveway and slow to a near stop at the entrance to my workplace. At other times I have long downhills with lots of turns so regen would be useful to bleed off excess speed gently. I'm more about economy, safety and control than racing though I'd like to be able to do 20 mph most of the time except perhaps climbing the steepest hills.

So to summarize a scenario:

half twist throttle
combo brake levers/trigger shifters (does this fit well with the half twist throttle?)
regen control on the left hand thumb of some type, preferrably proportional (not sure how the regens work)

Post Reply