## Search found 233 matches

Dec 09 2020 7:15pm
Forum: EBike Technical
Topic: Maximum centrifugal load for hub motor wheel
Replies: 13
Views: 371

### Maximum centrifugal load for hub motor wheel

I have a 45mm magnet height hub motor with Hubsinks inside a 24'' DH rim with DH tires and DH tube, so significant weight on the outside and spokes are only 13/14ga butted. When using torque mode on the ASI controller with 25% field weakening current, no load speed is very high. I stopped at about 2...
Dec 08 2020 8:28am
Forum: Items for Sale - New
Topic: Compact Field Oriented Controller, ASI + Grin, limited run
Replies: 1271
Views: 279340

### Re: Compact Field Oriented Controller, ASI + Grin, limited run

The jerking I only have when running the motor no load. It's happening at higher rpms than I reach while riding. But even with current regulator bandwidth set to 0, while riding near top speed deep in field weakening area, I have about 15% less power and motor current at 100% throttle than have at 5...
Dec 07 2020 12:59pm
Forum: Items for Sale - New
Topic: Compact Field Oriented Controller, ASI + Grin, limited run
Replies: 1271
Views: 279340

### Re: Compact Field Oriented Controller, ASI + Grin, limited run

With my ASI controller the motor is jerking at some point in field weakening area. The problem I have is that with no load and some field weakening, only for the first 10-15% of throttle setpoint, more throttle results in more motor current and higher rpm. Around 15% the motor is jerking. And for 20...
Dec 05 2020 11:35am
Forum: Battery Technology
Topic: Waste Heat Calculation Help
Replies: 8
Views: 383

### Re: Waste Heat Calculation Help

Just R * I^2, so at 10A 0.8W for copper or 3.2W for nickel.
Dec 05 2020 6:14am
Forum: Battery Technology
Topic: Waste Heat Calculation Help
Replies: 8
Views: 383

### Re: Waste Heat Calculation Help

The amount of heating power (in Watts) is R * I^2 (Resistance * Current^2). The resistance of the wire (in Ohm) is c * (length in meters) / (area in mm^2) Use c=0,0171 for copper and c=0,0693 for nickel. So 12.6cm of 0.27mm2 wire would have a resistance of 8mOhm in copper and 32mOhm in nickel. To ca...
Dec 04 2020 5:58pm
Forum: Battery Technology
Topic: Typical Internal Resistance of 18650 Pack
Replies: 16
Views: 778

### Re: Typical Internal Resistance of 18650 Pack

The <38mOhm value for one cell I used is for 1kHz AC, for DC it's more like 50mOhm, and MOSFET resistance of the BMS could also be about 10mOhm and it was a bit cold so I guess everything is fine. Are you not using a BMS for this battery and do you also measure it (voltage sag) divided by (battery a...
Dec 04 2020 1:33am
Forum: Battery Technology
Topic: Typical Internal Resistance of 18650 Pack
Replies: 16
Views: 778

### Re: Typical Internal Resistance of 18650 Pack

Thanks for the info! What cells do you use in your 16s12p pack?
Dec 03 2020 11:03pm
Forum: Battery Technology
Topic: Typical Internal Resistance of 18650 Pack
Replies: 16
Views: 778

### Re: Typical Internal Resistance of 18650 Pack

I did not build the pack myself, so unfortunately there are no fotos. I was just asking if anybody can post the internal resistance of his pack. If I assume an internal resistance of 38mOhm (lygte-info.dk writes <38mOhm), so for a 14S10P pack combined cell resistance would be 58mOhm. The resistance ...
Dec 03 2020 9:06pm
Forum: Battery Technology
Topic: Typical Internal Resistance of 18650 Pack
Replies: 16
Views: 778

### Re: Typical Internal Resistance of 18650 Pack

Of course there is no typical voltage for all 18650 packs. I am just asking if there are typical values for certain packs (like 13s5p mj1 or 14s5p GA or what ever) to see if it is normal that the internal resistance is 50% higher than the calculated value (without resistance of connections inside th...
Dec 03 2020 3:20am
Forum: Battery Technology
Topic: Typical Internal Resistance of 18650 Pack
Replies: 16
Views: 778

### Re: Typical Internal Resistance of 18650 Pack

My controller logs battery current and battery voltage. I am simply calculating it resistance = voltage sag divided by current. The 38mOhm was probably AC resistance. But shouldnt DC resistance be lower? Battery temperature was about 15 degrees Celsius. There was no significant difference between 90...
Dec 02 2020 11:46pm
Forum: Battery Technology
Topic: Typical Internal Resistance of 18650 Pack
Replies: 16
Views: 778

### Typical Internal Resistance of 18650 Pack

When calculating internal resistance of my 14S10P Sanyo GA pack based on voltage drop it is around 90-95mOhm. I read that the internal resistance of one GA cell should be <38mOhms, so I expected the internal resistance to be 14/10*38mOhm + 5mOhm (wire resistance) = <58mOhm. Are the 35mOhms caused by...
Nov 23 2020 12:34am
Forum: EBike General Discussion
Topic: Battery Crash Protection
Replies: 13
Views: 524

### Re: Battery Crash Protection

Do you think a sandwich (plate of hard material - foam - plate of hard material) has any advantages over just hard material outside and foam inside?
Nov 22 2020 11:31pm
Forum: EBike Technical
Topic: Hub Motor out of true
Replies: 6
Views: 215

### Re: Hub Motor out of true

No, I use a 3-arm gear puller
Nov 22 2020 10:23pm
Forum: EBike Technical
Topic: Hub Motor out of true
Replies: 6
Views: 215

### Re: Hub Motor out of true

It is "buckled" (out of true). Maybe 1mm at the spoke flange. It sits perfect inside the dropouts and is fixed by torque arms on both sides (connected to IS2000 mount on the left, and to a thread I cut into the frame on the right) The cover screws are only M4, so they should only be tighte...
Nov 22 2020 9:13pm
Forum: EBike Technical
Topic: Hub Motor out of true
Replies: 6
Views: 215

### Re: Hub Motor out of true

The problem is not the brake disc. The motor itself is not turning round, which caused the rim, the brake disc and the flywheel to be out of true. I checked it by holding the end of a zip tie to the spoke flange on the side where I have spoke elbows inside. I put the Statorade directly onto the roto...
Nov 22 2020 1:56pm
Forum: EBike Technical
Topic: Hub Motor out of true
Replies: 6
Views: 215

### Hub Motor out of true

On a 45mm magnet 3kw motor (very similar to mxus 3k), I have yesterday removed the right cover, added some more Statorade, and then reinstalled the right cover with silicone sealant. After that the motor was a bit out of true. Less than a millimeter on the spoke flange, but I had to retrue the rim a...
Nov 22 2020 4:32am
Forum: EBike General Discussion
Topic: Battery Crash Protection
Replies: 13
Views: 524

### Re: Battery Crash Protection

The pack is about 68mm wide. At the moment plus 2x 6mm yoga mat on each side. I don‘t want more than 4mm on each side. With the yoga mats knees are almost rubbing on the frame bag. I don’t do hard offroad riding with this bike. The bag is secure while riding (secured by about 10 velcros). When crash...
Nov 21 2020 4:05pm
Forum: EBike General Discussion
Topic: Battery Crash Protection
Replies: 13
Views: 524

### Re: Battery Crash Protection

Carbon Fibre plate. sorry
Nov 21 2020 1:58pm
Forum: EBike General Discussion
Topic: Battery Crash Protection
Replies: 13
Views: 524

### Battery Crash Protection

On one bike I have a large triangle battery inside a frame bag. Crash protection should be light and not too wide, so knees won't touch the frame bag while pedaling. At the moment I am using a 6mm yoga mat on both sides. Knees don't rub on the frame bag while pedaling, but it is really close. And th...
Nov 21 2020 12:41pm
Forum: EBike General Discussion
Topic: Alternative to Domino Throttle
Replies: 3
Views: 306

### Re: Alternative to Domino Throttle

I have used two brass thread inserts to repair the thread. Quite simple and now and it is as tight on the handlebar is it should.
Just need to drill out the holes and melt the thread inserts in with a soldering iron (remove all tin from the tip before)
Nov 15 2020 6:46pm
Forum: EBike General Discussion
Topic: Alternative to Domino Throttle
Replies: 3
Views: 306

### Re: Alternative to Domino Throttle

Same happened to me. Definitely feels way better than the Chinese stuff, but it is still far away from perfect.
Nov 15 2020 6:21pm
Forum: EBike General Discussion
Topic: Alternative to Domino Throttle
Replies: 3
Views: 306

### Alternative to Domino Throttle

Are the any other good quality throttles?
The feeling and controllability of the Domino is great. Unfortunately it needs quite some space, gets damaged by crashes easily and the thread is made of plastic. Also I don’t need the integrated switch it has.
Sep 29 2020 6:08pm
Forum: EBike General Discussion
Topic: Triangle Battery Bag hitting Chainring/Front Derailleur
Replies: 4
Views: 197

### Triangle Battery Bag hitting Chainring/Front Derailleur

I am looking for solutions on the following problem: https://i.ibb.co/WkbxLRy/DSC-3114.jpg There is a large 140 cell triangle battery + charger + controller inside a triangle frame bag. I will secure the battery inside the pack a bit by using velcros, but that alone won't do the job. The battery its...
Jul 09 2020 4:43pm
Forum: EBike General Discussion
Topic: Rear Derailleur Compatibilty for 5speed
Replies: 19
Views: 614

### Re: Rear Derailleur Compatibilty for 5speed

Domino throttle and thumb throttle for regen are on the right and I dont want to change that, so the shifter has to be on the left. There are non-index grip shifters for the left (at least they say that on the ebay description) but I dont know if cable length would be okay. I will probably try that....
Jul 09 2020 9:30am
Forum: EBike General Discussion
Topic: Rear Derailleur Compatibilty for 5speed
Replies: 19
Views: 614

### Re: Rear Derailleur Compatibilty for 5speed

Thanks, I think that’s the best option.
Did anybody already try if 3speed (non-index or converted to non-index ) twist grip shifters for front derailleurs would work with a 5speed rear derailleur?