Search found 211 matches

by PaulD
Apr 17 2019 1:14pm
Forum: E-Bike Non-hub Motor Drives
Topic: My RC Mid Drive with Single Stage Reduction
Replies: 138
Views: 8829

Re: My RC Mid Drive with Single Stage Reduction

Personally I think torque sensing and even a throttle is unnecessary on a low powered assist setups like this. When riding single track, reactions need to be instinctive. Pedal and brake are plenty to think about when tracks get fast and technical. If I was using your setup, I would have a single b...
by PaulD
Mar 25 2019 1:05pm
Forum: Items for Sale - Used
Topic: SOLD - GreyP 12kw E-bike - SOLD
Replies: 11
Views: 1068

Re: $5000 OBO GreyP 12kw E-bike - Mint Condition w/ 91 Miles

but what stands out with this bike, is the special geared crank, allows you to pedal at 43 MPH... and the bike is built to be able to pedal - get this - - EFFECTIVELY. My power calculator says you incur something like 250W of extra drag by pedaling at 43mph versus not pedaling. So sure, you can mak...
by PaulD
Mar 22 2019 12:09pm
Forum: E-Bike Non-hub Motor Drives
Topic: GNG X1-pro 3000w
Replies: 277
Views: 23312

Re: GNG X1-pro 3000w

I haven’t found a metal option for a PF30 to threaded BSA adapter. I was also concerned about running 3000W through it. Anyone here have experience with this? https://www.google.fi/search?q=FSA%20PF30%20Threaded%20Adapter%20B3167 This adapter is somewhat permanent. Very tight press fit, and supplie...
by PaulD
Mar 20 2019 9:38pm
Forum: Battery Technology
Topic: New weldless battery system crowdfunfing project
Replies: 71
Views: 2434

Re: New weldless battery system crowdfunfing project

Current and resistance measurement of the springs were done uncompressed, as compressing them could lead to something akin to a spring bypass. So, they were tested with a cell in place with very little contact force on the cell? The reason I ask is to help understand how much the contact resistance...
by PaulD
Mar 19 2019 12:49pm
Forum: Battery Technology
Topic: New weldless battery system crowdfunfing project
Replies: 71
Views: 2434

Re: New weldless battery system crowdfunfing project

BlueSwordM wrote:
Mar 19 2019 11:39am
That's why I've made my own BeCu spring design :)

Nickel plated BeCu C17530 springs.
Cool springs. How much spring force is on the cell when you ran your tests? 20A is impressive.
by PaulD
Feb 26 2019 3:41pm
Forum: E-Bike Technical
Topic: Torque sensor for 386 bb
Replies: 4
Views: 193

Re: Torque sensor for 386 bb

https://www.ebikes.ca/shop/electric-bicycle-parts/torque-sensors/sempu-140.html This is the only one I have found that comes close at 84mm, think it could work? I think that would work with Press-fit to Threaded adapters like this: https://www.amazon.com/Token-Products-Press-Threaded-Adapter/dp/B01...
by PaulD
Feb 25 2019 10:49pm
Forum: E-Bike Technical
Topic: Torque sensor for 386 bb
Replies: 4
Views: 193

Re: Torque sensor for 386 bb

Nobody makes one as far as I'm aware. I've been tempted to modify a Sempu T4 for this purpose. I think it's possible with some machining skills and time.
by PaulD
Jan 23 2019 4:47pm
Forum: E-vents
Topic: Sea Otter Classic 2019, April 11-14, Monterey California
Replies: 15
Views: 704

Re: Sea Otter Classic 2019, April 11-14, Monterrey California

That's new. Bummer. I raced my own drive system a few years ago, that was fully within the rules: class 1, 20mph, 500W (350W actually). I assume that Bosch and the bike industry doesn't like the idea of conversions. Makes sense. They are making bank on the false notion that you need to buy a whole n...
by PaulD
Jan 03 2019 12:57am
Forum: Motor Technology
Topic: asi bac 800 controller documentation and wiring
Replies: 3
Views: 360

Re: asi bac 800 controller documentation and wiring

Screenshot_20190102-214538.png
On the BAC 500, pin 1 is bottom right. I think it's the same.
If you have the mating connector, pin one usually has a tiny little arrow or triangle molded into it that points at pin 1.
by PaulD
Jan 02 2019 3:13pm
Forum: Battery Technology
Topic: Fuse-wire for individual cells, DIY Tesla style
Replies: 113
Views: 15629

Re: Fuse-wire for individual cells, DIY Tesla style

Here is the picture of the failed negative fuse wire bond; Yikes, that looks tight. I agree that spot welding a nickel strap from PCB to cell might be the easiest repair, unless you have a friend with a wire bonder. :D You will probably need some tiny spot welding electrodes to fit in that space, t...
by PaulD
Dec 04 2018 4:08pm
Forum: E-Bike Non-hub Motor Drives
Topic: Calling all Belt Drive Experts
Replies: 82
Views: 3441

Re: Calling all Belt Drive Experts

Static tension for a 9mm wide, 5mm pitch GT2 belt in this config should be about 250lbs according to Gates documentation. Just to clarify, 250lbs is the total load on the motor shaft (125 lbs per span) per the equation: belt tension equation.png I think this is unnecessarily high... we'll see. Also...
by PaulD
Dec 03 2018 6:03pm
Forum: E-Bike Non-hub Motor Drives
Topic: Calling all Belt Drive Experts
Replies: 82
Views: 3441

Re: Calling all Belt Drive Experts

Nice looking setup! I'm curious to see if it's possible to run a belt at much lower tension. I wouldn't be surprised if there is some margin in that 250 lb figure. Maybe I can trade tension for belt life, as long as the belt is not skipping (much...) At 250 lb, probably with a cyclic component, I w...
by PaulD
Dec 03 2018 2:02pm
Forum: E-Bike Non-hub Motor Drives
Topic: Calling all Belt Drive Experts
Replies: 82
Views: 3441

Re: Calling all Belt Drive Experts

Doing a crank drive belt drive is a tougher problem to solve than a rear wheel mount for a given power level. If we want 60-70Nm of crank torque, using a pulley that is about the same diameter of 32T chainring, we end up with 225 lbs of peak drive tension. Static tension for a 9mm wide, 5mm pitch GT...
by PaulD
Nov 28 2018 10:12pm
Forum: Battery Technology
Topic: any experience with Outlast phase-change material?
Replies: 7
Views: 415

Re: any experience with Outlast phase-change material?

No experience with that material, but keep in mind it softens up at phase change temperature. The datasheet says shore 45A at 70c, which is like pencil eraser stiffness. You'll need to have cell support structure other than this.
by PaulD
Nov 22 2018 10:33am
Forum: E-Bike Non-hub Motor Drives
Topic: PaulD's lightweight mid drive development
Replies: 45
Views: 6583

Re: PaulD's lightweight mid drive development

micah78 wrote:
Nov 22 2018 3:31am
I will follow this post and buy it when it's ready.
Thanks Micah, it's looking like January-February is our new target. Beta testing is process, and we have had some delays on our battery potting equipment and other bits that have pushed things later. It's the nature of product development!
by PaulD
Nov 20 2018 9:23am
Forum: E-Bike Technical
Topic: Using crankset with ANT+ powermeter as PAS
Replies: 4
Views: 524

Re: Using crankset with ANT+ powermeter as PAS

Sorry to dig this up.. but I've been thinking about this.. There are many new power meters on the market, I saw one the other day discounted to around $200AUD. which would make an awesome Torque based throttle. Before i get into it, has anyone got any ideas like this, or reasons why it wouldn't wor...
by PaulD
Nov 19 2018 2:42pm
Forum: E-Bike Non-hub Motor Drives
Topic: PaulD's lightweight mid drive development
Replies: 45
Views: 6583

Re: PaulD's lightweight mid drive development

Thanks guys! We are good on funding for a while, our main constraint is time. In fact, I am hoping to hire or contract the help of an electrical engineer soon. I am pretty slammed, and have a young one at home, so it's tough to keep things going at the pace that I'd like. Perhaps I'll post a job lis...
by PaulD
Nov 16 2018 1:57pm
Forum: E-Bike Non-hub Motor Drives
Topic: PaulD's lightweight mid drive development
Replies: 45
Views: 6583

Re: PaulD's lightweight mid drive development

Subscribed! I am a builder/developer in the oh-so-tiny off-road handcycling scene. E-assist has proven to be a game-changer. However, most of the DIY kits don't integrate too well into the available equipment. This kit looks like it has fantastic potential. Thanks ions. We are making good progress,...
by PaulD
Oct 15 2018 10:33am
Forum: Battery Technology
Topic: VOC sensor for detecting electrolyte leakage... before it's too late!
Replies: 16
Views: 936

Re: VOC sensor for detecting electrolyte leakage... before it's too late!

Nice idea. I had a co-worker a while back that was obsessed with using a breathalizer for detecting electrolyte. I don't think he ever actually tried it. Interested to see if this works.
by PaulD
Oct 10 2018 3:19pm
Forum: E-Bike Technical
Topic: Shrink Solder Sleeve Butt Connectors
Replies: 6
Views: 529

Re: Shrink Solder Sleeve Butt Connectors

Amazon has them for a slightly more reasonable cost. About $0.25 each. Splicing some 8-pin cables into 5-pin (display) and 2-pin (headlight) today. I'm borrowing a rad Hakko hot air station for doing these. I think a heat gun with a nozzle would work well too.
heatshrinksoldersplices.png
heatshrinksoldersplices.png (321.4 KiB) Viewed 375 times
by PaulD
Oct 01 2018 10:41pm
Forum: E-Bike Non-hub Motor Drives
Topic: PaulD's lightweight mid drive development
Replies: 45
Views: 6583

Re: PaulD's lightweight mid drive development - Looking for Beta Testers

Another quick update. The 100mm Sempu T4 torque sensor allows us to install this kit (with a few extra spacers) onto a fatbike with 4.7" tires. Looking forward to winter, or a trip to the coast! fatbike1.png fatbike2.png fatbike3.png Also, I am looking for Beta testers for the kit. We have a few Bet...
by PaulD
Aug 31 2018 6:05pm
Forum: E-Bike Non-hub Motor Drives
Topic: Torque sensor BB DIY mid drive questions
Replies: 4
Views: 560

Re: Torque sensor BB DIY mid drive questions

Although not commonly advertised, Sempu can make a T3 model torque sensing bottom bracket which works with ISIS crank arms instead of Square Taper. Electrically and dimensionally it is said to be identical to the T4. If you would prefer the ISIS version and cannot find it for sale, PM me and I will...
by PaulD
Aug 28 2018 3:54pm
Forum: Battery Technology
Topic: kWeld - "Next level" DIY battery spot welder
Replies: 617
Views: 74891

Re: kWeld - "Next level" DIY battery spot welder

Thanks@pictures. Regarding current, I meant what current level do you get with kWeld? Ha, oops, yeah that makes more sense. I get about 880-900A. BTW, I bumped up my energy to 40J, and I'm getting stronger welds. Ron, I attached a pic of the tabs and the fixtures I use to bend them to mate up to th...
by PaulD
Aug 28 2018 1:04pm
Forum: Battery Technology
Topic: kWeld - "Next level" DIY battery spot welder
Replies: 617
Views: 74891

Re: kWeld - "Next level" DIY battery spot welder

tatus1969 wrote:
Aug 28 2018 1:53am
That looks awesome! Can I use it for my web site?

Your battery looks quite small, how many amps does it do?
Thanks, and no problem, you can use the picture.
The pack is 10.5ah, 15A peak. It's for a lightweight, lower power drive.
by PaulD
Aug 27 2018 7:21pm
Forum: Battery Technology
Topic: kWeld - "Next level" DIY battery spot welder
Replies: 617
Views: 74891

Re: kWeld - "Next level" DIY battery spot welder

:shock: Now that’s what I call an incredibly good set up! Thanks! This is the second revision, the third will have some needle bearings in between the two plastic electrode holders to reduce friction, and keep the electrodes well aligned. PaulD (and anyone else reading this thread), please shorten ...