## Search found 144 matches

Apr 03 2019 5:05pm
Forum: General Discussion
Topic: math problem involving gear inches: help?
Replies: 2
Views: 481

### math problem involving gear inches: help?

I need some help doing some mathematical calculations for my delta trike (20 inch drive wheel). It has a complex drivetrain, so calculating the gearing is not very straightforward: it has front chainrings and 2 intermediary sprockets between the chainrings and the sprocket on the rear wheel, one on ...
Aug 15 2018 2:45pm
Forum: E-Bike General Discussion
Topic: Recommendations wanted: mid-drive ca. 250w kit w/torque sensing
Replies: 9
Views: 690

### Re: Recommendations wanted: mid-drive ca. 250w kit w/torque sensing

Well, I thought I was wrapping things up here, since no further comments had been made for quite some time. And now, some new input. Thanks for the additional information docw009 and John and Cecil, and especially for the link to an alternative kit.
Aug 15 2018 12:56pm
Forum: E-Bike General Discussion
Topic: Recommendations wanted: mid-drive ca. 250w kit w/torque sensing
Replies: 9
Views: 690

### Re: Recommendations wanted: mid-drive ca. 250w kit w/torque sensing

With the aim of wrapping up this discussion I should mention that I finally ran across this thread: https://endless-sphere.com/forums/viewtopic.php?f=28&t=79788&hilit=Tsdz2 . That's a pretty lengthy discussion of the very kit I asked about in my second contribution to the current thread. I guess I h...
Aug 08 2018 11:46pm
Forum: E-Bike General Discussion
Topic: Help me turn my touring bike into a car replacement
Replies: 13
Views: 927

### Re: Help me turn my touring bike into a car replacement

Here's a metric that is somewhat relevant but does not address your situation directly. I have a recumbent tandem trike (delta) to which I added electric assist a few years ago, using help gotten from this forum. My set-up has a range approximately close to what you're aiming for: when I first set i...
Aug 08 2018 9:28pm
Forum: E-Bike General Discussion
Topic: Recommendations wanted: mid-drive ca. 250w kit w/torque sensing
Replies: 9
Views: 690

### Re: Recommendations wanted: mid-drive ca. 250w kit w/torque sensing

Thanks for your input, wturber. The bike will actually be located and used in the state of MI. I'm not sure what are the regulations there. But I'm pretty sure my friend's logic in prefering a lower-power assist has to do with the fact that he would like for his grandson to be more physically active...
Aug 08 2018 2:49pm
Forum: E-Bike General Discussion
Topic: Recommendations wanted: mid-drive ca. 250w kit w/torque sensing
Replies: 9
Views: 690

### Re: Recommendations wanted: mid-drive ca. 250w kit w/torque sensing

Anyone have experience with the Tongsheng TSDZ2 Mid Drive kit (https://www.amazon.com/TSDZ-Version-Tongsheng-Conversion-Torque/dp/B01MYRB6Q6)? That's the one we're looking at. Looks like it could be readily adapted to this bike: https://www.rei.com/product/851140/electra-townie-7d-bike. Bottom brack...
Jul 30 2018 11:00pm
Forum: E-Bike General Discussion
Topic: Recommendations wanted: mid-drive ca. 250w kit w/torque sensing
Replies: 9
Views: 690

### Recommendations wanted: mid-drive ca. 250w kit w/torque sensing

Hi. I've got a friend who will be setting up an electric assist bike for his college-age grandson for around-town commuting. He bought the bike already. It's a bike sold by REI, the Electra Townie. What he's interested in is a fairly low-power (say, 250 watt) mid drive kit with torque sensing that h...
Sep 22 2016 10:50am
Forum: Battery Technology
Topic: BMS shutoff or battery top-up/partial drain for storage?
Replies: 4
Views: 528

### BMS shutoff or battery top-up/partial drain for storage?

I'm grappling with the issue of battery storage--think over the cold, upper-midwest winter, where biking outdoors is at best unpleasant, at worst impossible: during these intervals, the battery must sit largely unused and thus in storage. My LiFePO4 battery might have to sit idle for 3 months per ye...
Sep 21 2016 4:16pm
Forum: Battery Technology
Topic: Test cell V's in Ping LiFePO battery w/out dissecting it?
Replies: 26
Views: 4893

### Re: Test cell V's in Ping LiFePO battery w/out dissecting it

Yeah, the crankarm issue on tandems carries its own set of complications when it comes to mid-drives. But I was actually more curious about how you mounted the motor to the frame: the downtube on the standard upright bikes these mounting kits are made for is pretty much absent on a delta trike, and ...
Sep 21 2016 12:30pm
Forum: Battery Technology
Topic: Test cell V's in Ping LiFePO battery w/out dissecting it?
Replies: 26
Views: 4893

### Re: Test cell V's in Ping LiFePO battery w/out dissecting it

Thanks for your response, Rassy. Do you ever have misgivings about your storage strategy, given that storing these batteries at full charge is said to cause them to degrade? (see the recent thread "Is mantaining a cell at 3.6V overcharging?," where I specifically asked about advisability of long-ter...
Sep 20 2016 3:42pm
Forum: Battery Technology
Topic: My excellent adventure through some battery builds
Replies: 195
Views: 30164

### Re: My excellent adventure through some battery builds

Interesting thread. Not working in IT, I don't have a source for free, cast-off laptop batteries. I'm also not real well versed in electronics. But I like the concept of, not just free, but of making good use of materials others just want to get rid of. Yet my main question in posting here is, why c...
Sep 20 2016 3:13pm
Forum: Battery Technology
Topic: Test cell V's in Ping LiFePO battery w/out dissecting it?
Replies: 26
Views: 4893

### Re: Test cell V's in Ping LiFePO battery w/out dissecting it

Sorry, but I really cannot understand what you are trying to say in your latest response, 999zip999. Something(s?) crucial to deciphering your meaning seems to be missing there. I'm trying to resolve discussion in this thread regarding battery balancing into some prescriptive advice I can follow in ...
Sep 20 2016 12:50pm
Forum: General Discussion
Topic: Triple chainrings: a flawed concept/design?
Replies: 10
Views: 974

### Re: Triple chainrings: a flawed concept/design?

Shifting up to the bigger sprockets is not an issue ? I've never had a problem shifting onto the large chainring on any of these bikes (well, except for an isolated incident where I had misadjusted the derailleur and wound up overshifting [chain fell off the crank arm side]). Another factor all the...
Sep 19 2016 10:28pm
Forum: General Discussion
Topic: Triple chainrings: a flawed concept/design?
Replies: 10
Views: 974

### Re: Triple chainrings: a flawed concept/design?

is this only the front chain ring, when shifting to the smaller sprockets ?... i would expect more issues shifting up the sprocket sizes on the rear cassette. Yes, none of the three will shift to the small chainring when the chain is under the tension of climbing a hill. On the first tandem I thoug...
Sep 19 2016 8:18pm
Forum: Battery Technology
Topic: Test cell V's in Ping LiFePO battery w/out dissecting it?
Replies: 26
Views: 4893

### Re: Test cell V's in Ping LiFePO battery w/out dissecting it

It got unbalance because cells 1 ,2 & 3 are the cells that power the bms. Yes just 3 cells so left alone it will become unbalance due to the bms. How many led lights turn on now ? Oh your picture just came up I count 12 leds. Good Yes, I finally got all LED's to come on by leaving the charger conne...
Sep 19 2016 5:07pm
Forum: General Discussion
Topic: Triple chainrings: a flawed concept/design?
Replies: 10
Views: 974

### Re: Triple chainrings: a flawed concept/design?

I believe Sram/Shimano components--I'd have to double check to give particulars. I've actually got 3 recumbent tandems, all with slightly differing components, and the shifting problem referenced applies to all 3. If the subtle pedal-cadence adjustment you speak of is the solution, that will be very...
Sep 19 2016 4:16pm
Forum: General Discussion
Topic: Triple chainrings: a flawed concept/design?
Replies: 10
Views: 974

### Triple chainrings: a flawed concept/design?

Triple chainrings are, as we know, found on all kinds of bikes, including electrified bikes like mine. But the topic I wish to broach applies equally, I think, to both categories. And it actually arises out of my biking experiences prior to doing my electrification projects. My enagement with bicycl...
Sep 19 2016 12:23pm
Forum: Battery Technology
Topic: Test cell V's in Ping LiFePO battery w/out dissecting it?
Replies: 26
Views: 4893

### Re: Test cell V's in Ping LiFePO battery w/out dissecting it

Thanks for the further input and explanations, Rassy. I have another, perhaps daft question, regarding the lighted LED's we're discussing. They're all on now, and have been since I connected the battery last night and got the "charge complete" message from the CS. So when you say "the actual balanci...
Sep 18 2016 7:21pm
Forum: Battery Technology
Topic: Test cell V's in Ping LiFePO battery w/out dissecting it?
Replies: 26
Views: 4893

### Re: Test cell V's in Ping LiFePO battery w/out dissecting it

Wayover, it looks like you are on top of your problem now. Appearances can be deceiving :). If "on top" you mean I am pretty close to having, or maybe even already have, all my cells balanced, you may be right. I think I'll try one more charging cycle using a standard LiFePO profile to test that. B...
Sep 18 2016 6:31pm
Forum: Battery Technology
Topic: Is mantaining a cell at 3.6V overcharging?
Replies: 8
Views: 1015

### Re: Is mantaining a cell at 3.6V overcharging?

With apologies if I am side-trackiing this thread, I would really like to know, as someone with a very limited comprehension of issues like battery chemistries and even electronics in general, to what level I should be discharging my LiFePO4 battery for winter storage. Sometime within the next coupl...
Sep 18 2016 8:09am
Forum: Battery Technology
Topic: Is mantaining a cell at 3.6V overcharging?
Replies: 8
Views: 1015

### Re: Is mantaining a cell at 3.6V overcharging?

Tek nailed it. <snip> LiFePO4 is very tolerant, 3.8V-4.0V can be tolerated by some short term without noticeable harm. They should not be stored at full voltage long term though. Time and temp degrades them more rapidly, including being stored at higher potential. But: LiFePo4 is unique among lithi...
Sep 17 2016 1:37pm
Forum: Battery Technology
Topic: Test cell V's in Ping LiFePO battery w/out dissecting it?
Replies: 26
Views: 4893

### Re: Test cell V's in Ping LiFePO battery w/out dissecting it

I'm not completely understanding your remarks, 999zip999, though the part about leaving the battery hooked to the charger for 24 hours (and maybe more?) is more or less clear. So I'm learning some things about battery balancing. I left the battery hooked to the charger yesterday for 14 hours while a...
Sep 15 2016 11:29pm
Forum: Battery Technology
Topic: Test cell V's in Ping LiFePO battery w/out dissecting it?
Replies: 26
Views: 4893

### Re: Test cell V's in Ping LiFePO battery w/out dissecting it

I consulted with my more electronics-savvy friend about this. He said the right way to do it would be to touch the red probe of the volt meter to the contact on the back of the header to which the small black wire leads, and the black probe of the volt meter to the large black wire soldered to the e...
Sep 15 2016 10:35am
Forum: Battery Technology
Topic: Test cell V's in Ping LiFePO battery w/out dissecting it?
Replies: 26
Views: 4893

### Re: Test cell V's in Ping LiFePO battery w/out dissecting it

Thanks so much for the additional tips and graphics, Gregory and cell_man. At this point though I'm having a bit of trouble--due to my own rudimentary understanding of electronics--comprehending what I should be doing to get a voltage reading from the 12th cell. Let me describe in my own words/under...
Sep 14 2016 10:39pm
Forum: Battery Technology
Topic: Test cell V's in Ping LiFePO battery w/out dissecting it?
Replies: 26
Views: 4893

### Re: Test cell V's in Ping LiFePO battery w/out dissecting it

Thanks for the great tips and even photos! I was suspecting that might be where I could check, but was uncertain where to poke the probes. Using those tips, I was able to get voltages that appear to be close to what individual cells should be (all in the 3.31-3.32 volts range). At least for 11 cells...