Search found 3784 matches

by johnrobholmes
Oct 22 2019 6:58am
Forum: Items for Sale - New
Topic: Moped Rims and Wheels, 36 hole, 16" 17" 18" 19"
Replies: 175
Views: 39302

Re: Moped Rims and Wheels, 36 hole, 16" 17" 18" 19"

I'm currently not selling rims. A few hundred takes up a lot of floor space that I dont have to spare.
by johnrobholmes
Sep 29 2019 7:28am
Forum: E-Bike General Discussion
Topic: what's the best nipples to use when rebuilding a hub motor?
Replies: 14
Views: 445

Re: what's the best nipples to use when rebuilding a hub motor?

ClintBX wrote:
Sep 29 2019 2:36am
I just got a response from the vendor. He tells me they are copper. I didn't know there were copper nipples. Thoughts?
Sounds like a vendor that is just flipping parts. They would be brass. There are many grades of brass though. Cheap nipples will be cheap materials.
by johnrobholmes
Sep 28 2019 4:46pm
Forum: E-Bike General Discussion
Topic: what's the best nipples to use when rebuilding a hub motor?
Replies: 14
Views: 445

Re: what's the best nipples to use when rebuilding a hub motor?

Name brand. The ones from Dan's competition aren't too bad, but they aren't great either. Anything ebay or amazon is bottom of the barrel unless it's a trusted vendor selling name brand. Plenty of fakes from shady vendors though.
by johnrobholmes
Sep 28 2019 9:16am
Forum: Motor Technology
Topic: Open loop regen braking
Replies: 1
Views: 206

Re: Open loop regen braking

My Google fu of ES finally resulted in this thread from Justin which suggests that bouncing the low side fets will get my result without knowing motor or current direction. Only half the strength of a full brake, but I'm attempting to do this blindly without feedback or modeled motor parameters. htt...
by johnrobholmes
Sep 28 2019 9:07am
Forum: Motor Technology
Topic: Open loop regen braking
Replies: 1
Views: 206

Open loop regen braking

I'm doing some thinking about how regen braking can be implemented without a current sensor. For simplicity, i consider an h bridge. Typically, it seems that regen braking is done by reversing the bridge from state A to B, but without a current sensor it will reverse motor direction once bemf is ext...
by johnrobholmes
Sep 24 2019 8:31am
Forum: E-Bike Technical
Topic: XPD: open-source keywin e-bike lab replacement
Replies: 600
Views: 134468

Re: XPD: open-source keywin e-bike lab replacement

figured it out. pyserial wasn't installed. Also is no longer listed in the sourceforge downloads so I found it here https://sourceforge.net/projects/pyserial/
by johnrobholmes
Sep 23 2019 5:08pm
Forum: E-Bike Technical
Topic: XPD: open-source keywin e-bike lab replacement
Replies: 600
Views: 134468

Re: XPD: open-source keywin e-bike lab replacement

I'm getting no traction with a fresh install on a newer computer, win7. Seems the xpd.pyw file isn't doing anything. Did the python and gtk install, ive got the idle and command line working. pyw file does nothing, no gui now. what gives? Been a while since I had to trudge through this and my last c...
by johnrobholmes
Jul 01 2019 9:15am
Forum: E-Bike Non-hub Motor Drives
Topic: Sur-Ron - New Mid drive Bike
Replies: 4234
Views: 366722

Re: Sur-Ron - New Mid drive Bike

This bike is so damn good now after I upgraded my brakes. It just stops so much easier and faster, you have way more control over the bike with better brakes which allows you to do many more things. The brake levers are way more comfortable also and easier to cover with one finger all the time whil...
by johnrobholmes
Jul 01 2019 9:13am
Forum: E-Bike Non-hub Motor Drives
Topic: Sur-Ron - New Mid drive Bike
Replies: 4234
Views: 366722

Re: Sur-Ron - New Mid drive Bike

I was heavily considering getting an X . Saw the Ludi R version and broke down and got it instead. I blame getting 1 million views on my first Sur Ron vid for this decision :lol: I know this forum doesn't moan and groan too much over the prices, especially since most of us have been here since 10k t...
by johnrobholmes
Jul 01 2019 9:06am
Forum: E-Bike Technical
Topic: Yuyang king controller wiring
Replies: 5
Views: 416

Re: Yuyang king controller wiring

Well, it worked. For about 5 minutes. As I was going through all the phase/ sensor combinations the ESC quit responding. Hooked up another ESC and the motor, batt, and throttle are fine. Bummer! Took the controller apart and no damaged or smoked components to be seen. Time to contact Luna.
by johnrobholmes
Jun 29 2019 7:18am
Forum: E-Bike Technical
Topic: Yuyang king controller wiring
Replies: 5
Views: 416

Re: Yuyang king controller wiring

Excellent, thank you. I didn't want to assume it was batt + and fry it. Seems just as plausible that it could have been a 5v+ enable circuit.

Thanks again!


Anybody know the quiescent current of these controllers when it's not turned on?
by johnrobholmes
Jun 28 2019 9:30pm
Forum: E-Bike Technical
Topic: Yuyang king controller wiring
Replies: 5
Views: 416

Yuyang king controller wiring

A buddy got a yuyang from Luna cycle. Bluetooth 60a 72v one. I'm guessing we need to connect the "power switch" wire to batt positive like the old xie chang, cause it ain't booting up. Confirmation before I crack open the case to trace it and pretend I know what I'm doing? :lol:
by johnrobholmes
May 08 2019 10:29am
Forum: E-Bike Non-hub Motor Drives
Topic: Sur-Ron - New Mid drive Bike
Replies: 4234
Views: 366722

Re: Sur-Ron - New Mid drive Bike

I can report that the BMS has extremely low quiescent current. Broke my leg 4 months ago (so no riding lately) and the battery has been sitting for at least 6 months total now with hardly a drop to the voltage or % on the display. I've been monitoring monthly. Very pleased.
by johnrobholmes
May 08 2019 10:22am
Forum: Items for Sale - New
Topic: Moped Rims and Wheels, 36 hole, 16" 17" 18" 19"
Replies: 175
Views: 39302

Re: Moped Rims and Wheels, 36 hole, 16" 17" 18" 19"

That would heavily depend on the rim you use. It will be near the length of a bmx rim. We also just restocked the Moped style nipples. 14, 13, and 12ga compatible nipples that mate into many common moto rims. I'm currently not rolling spokes because we finally wore the machine out enough that it's n...
by johnrobholmes
Oct 11 2018 11:50am
Forum: E-Scooter and Motorcycle General Discussion
Topic: Alta Motors Redshift
Replies: 122
Views: 9683

Re: Alta Motors Redshift

Excellent observations, thank you for sharing. Sounds like I would be a map2 sort of rider. I'm considering one of them now :lol:


How loud is the electronic switching noise compared to the Sur Ron? Chain noise?
by johnrobholmes
Sep 04 2018 4:53pm
Forum: E-Bike Non-hub Motor Drives
Topic: Sur-Ron - New Mid drive Bike
Replies: 4234
Views: 366722

Re: Sur-Ron - New Mid drive Bike

I put the 58t rear sprocket on my bike with the stock rear wheel. Same story other people have, it has great low end but feels gutless past 15mph since there isn't enough load now. The 17" wheel with the 48t was perfect. I think between 55 and 52t would be a much better spot for the stock system. O...
by johnrobholmes
Aug 31 2018 10:21am
Forum: E-Bike Non-hub Motor Drives
Topic: Sur-Ron - New Mid drive Bike
Replies: 4234
Views: 366722

Re: Sur-Ron - New Mid drive Bike

I put the 58t rear sprocket on my bike with the stock rear wheel. Same story other people have, it has great low end but feels gutless past 15mph since there isn't enough load now. The 17" wheel with the 48t was perfect. I think between 55 and 52t would be a much better spot for the stock system. Or...
by johnrobholmes
Aug 04 2018 2:22pm
Forum: E-Bike Non-hub Motor Drives
Topic: Sur-Ron - New Mid drive Bike
Replies: 4234
Views: 366722

Re: Sur-Ron - New Mid drive Bike

I got sick of the first gen air shock needing constant work.

by johnrobholmes
Aug 03 2018 7:20pm
Forum: E-Bike Technical
Topic: The wheel-building spoke-lacing thread, post your tips
Replies: 242
Views: 42126

Re: The wheel-building spoke-lacing thread, post your tips

Doesn’t really matter unless the rim is so deep that you need longer nipples to reach down to the eyelets during assembly.
by johnrobholmes
Jun 16 2018 7:32pm
Forum: E-Bike General Discussion
Topic: Why are more of you DIYers not in the e-bike business?
Replies: 127
Views: 9453

Re: Why are more of you DIYers not in the e-bike business?

I wasn't just flipping cheap goods for triple the price of online though, that is a game that anybody could have done. Quality controllers, quality batteries, and handbuilt wheels that wouldn't immediately start breaking spokes. We were simply trying to sell quality kits and bikes instead of the che...
by johnrobholmes
Jun 15 2018 2:24am
Forum: E-Bike General Discussion
Topic: Why are more of you DIYers not in the e-bike business?
Replies: 127
Views: 9453

Re: Why are more of you DIYers not in the e-bike business?

I think others have put it into good terms on why not to get into the ebike business. Here is my reason why I got out. People want you to make all the decisions, do all the leg work, tell them what to do to build a bike. Then they buy $30 in spokes after taking a few hours in time. Hey, you do reali...
by johnrobholmes
Jun 11 2018 10:34pm
Forum: E-Bike Non-hub Motor Drives
Topic: Sur-Ron - New Mid drive Bike
Replies: 4234
Views: 366722

Re: Sur-Ron - New Mid drive Bike

I did a 5 month review. Probably nothing new to yall here, so I kinda forgot to post it. I'm feeling about the same today, loving to ride it a lot.

by johnrobholmes
Jun 01 2018 8:17pm
Forum: Motor Technology
Topic: FOC identification
Replies: 10
Views: 925

Re: FOC identification

It is potted so I can't really get into it without destruction. I have asked the company to reference the type and position of current sensors if they would like to give me some information to go on.
by johnrobholmes
May 31 2018 11:09pm
Forum: Motor Technology
Topic: FOC identification
Replies: 10
Views: 925

Re: FOC identification

A hobbywing unit. It is only compatible with their motors and offers no tuning of motor parameter, so it's quite limited in this regard.