Search found 4043 matches

by johnrobholmes
Feb 02, 2018 4:00 pm
Forum: E-Bike Non-hub Motor Drives
Topic: Sur-Ron - New Mid drive Bike from China
Replies: 508
Views: 27402

Re: Sur-Ron - New Mid drive Bike from China

Got the email, thanks! I'll get back to you asap, we should definitely meet up and you can take this thing for a test ride. I suppose I could let the PMs go back on here. Used to be nuts trying to keep up with them, but since I"m not actively selling stuff for ebikes any longer it probably wouldn't ...
by johnrobholmes
Jan 31, 2018 11:21 am
Forum: E-Bike Non-hub Motor Drives
Topic: Sur-Ron - New Mid drive Bike from China
Replies: 508
Views: 27402

Re: Sur-Ron - New Mid drive Bike from China

Anybody gotten past 1600km? I have concerns about the front hub flange stress cracking because of the spoke diameter, and we always saw the fractures or spoke head failure around the 1600km mark. The length of the spokes in a 19" may be the saving grace, but the flange width is not really wide enoug...
by johnrobholmes
Jan 31, 2018 11:12 am
Forum: E-Bike Non-hub Motor Drives
Topic: Sur-Ron - New Mid drive Bike from China
Replies: 508
Views: 27402

Re: Sur-Ron - New Mid drive Bike from China

yeah, a big truck of awesome!
by johnrobholmes
Jan 05, 2018 10:45 am
Forum: E-Bike Non-hub Motor Drives
Topic: Sur-Ron - New Mid drive Bike from China
Replies: 508
Views: 27402

Re: Sur-Ron - New Mid drive Bike from China

Got it figured out. Green wire with black stripe that loops out of the battery monitoring harness, it needs to be uncut. There is also a limp mode when the battery is low. balance charge plus connecting the green wire together got plenty of speed and power. Yehaw!
by johnrobholmes
Jan 05, 2018 8:08 am
Forum: E-Bike Technical
Topic: DIY BLDC Controller Wave forms + Snubber
Replies: 9
Views: 445

Re: DIY BLDC Controller Wave forms + Snubber

Looks like a cool project. Hook some motor up and see how stable to gates are.
by johnrobholmes
Jan 05, 2018 7:56 am
Forum: E-Bike Non-hub Motor Drives
Topic: Sur-Ron - New Mid drive Bike from China
Replies: 508
Views: 27402

Re: Sur-Ron - New Mid drive Bike from China

Yeah, there is a chance I'll build wheels again. I just dislike the volume of space the rims take up. I was actually thinking a set of 17s for off road would be pretty sweet since I don't need the top speed. I'm going back to school this month for engineering, gonna give another shake at controllers.
by johnrobholmes
Jan 04, 2018 11:55 pm
Forum: E-Bike Non-hub Motor Drives
Topic: Sur-Ron - New Mid drive Bike from China
Replies: 508
Views: 27402

Re: Sur-Ron - New Mid drive Bike from China

The motor is finned. It sounds like a trap controller, too thunky between poles to be sine. I'll certainly be looking for methods to get more amps.
by johnrobholmes
Jan 04, 2018 9:27 pm
Forum: E-Bike Non-hub Motor Drives
Topic: Sur-Ron - New Mid drive Bike from China
Replies: 508
Views: 27402

Re: Sur-Ron - New Mid drive Bike from China

There is an extra loop on the battery monitor plug , and cutting that brought the speed down to 10kpmh. There is a red wire in the battery area with a fuse, disconnecting that prevented the bike from booting up. I was told it is "a wire" that gets cut by the rep, so there's that. I'll get some pics ...
by johnrobholmes
Jan 04, 2018 8:57 pm
Forum: E-Bike Non-hub Motor Drives
Topic: Sur-Ron - New Mid drive Bike from China
Replies: 508
Views: 27402

Re: Sur-Ron - New Mid drive Bike from China

Also wanted to mention, the battery was totally dead. Wouldn't even allow a charge or display SOC. After 3 charger resets it started. Gonna keep an eye on capacity, makes me wonder if it sat that way for a few months.
by johnrobholmes
Jan 04, 2018 8:29 pm
Forum: E-Bike Non-hub Motor Drives
Topic: Sur-Ron - New Mid drive Bike from China
Replies: 508
Views: 27402

Re: Sur-Ron - New Mid drive Bike from China

I got one from Luna and the speed restriction was still on. Anyone know the procedure to get full speed? I nipped the green wire above the battery and speed went from 40kmph to 10kmph top speed, so that didn't seem to be the right one, lol! Looks decent so far. Not impressed with wheels, but they at...
by johnrobholmes
Apr 28, 2017 11:22 am
Forum: Items for Sale - New
Topic: Moped Rims and Wheels, 36 hole, 16" 17" 18" 19"
Replies: 169
Views: 30727

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

Been a while fellas! We just got a short shipment of 17" "rear" style rims for large hubmotors. We also have plenty of 12ga compatible nipples, along with 10ga precut spokes and nipples for cromotor size. Because of the warehouse space required for rims, and since my spoke machine is not functioning...
by johnrobholmes
Jan 25, 2016 1:51 pm
Forum: E-Bike Technical
Topic: Definitive Tests on the Heating and Cooling of Hub Motors
Replies: 1982
Views: 255977

Re: Definitive Tests on the Heating and Cooling of Hub Motor

it wipes out easy with a paper towel, no big deal.
by johnrobholmes
Jan 25, 2016 1:00 pm
Forum: E-Bike Technical
Topic: Definitive Tests on the Heating and Cooling of Hub Motors
Replies: 1982
Views: 255977

Re: Definitive Tests on the Heating and Cooling of Hub Motor

The problem with running a no load test is that the power consumption is very low. 100-200w at most depending on the voltage. Even if you run the motor for extended periods of time to let the motor's heat saturate you still don't get a good idea of real world usage where power is 10-20x if not more...
by johnrobholmes
Jan 10, 2016 9:10 am
Forum: Items for Sale - Used
Topic: SOLD: Pair 24v DC 3.3A 110 RPM Wheelchair Motors
Replies: 12
Views: 571

Re: For Sale: Pair 24v DC 3.3A 110 RPM Wheelchair Motors

I'll take em. What size is the tire?
by johnrobholmes
Jan 10, 2016 9:01 am
Forum: Items for Sale - New
Topic: Moped Rims and Wheels, 36 hole, 16" 17" 18" 19"
Replies: 169
Views: 30727

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

The factory didn't even make 3/4 of what I ordered too, so I don't see these lasting the length it takes them to make. Searching for new factories right now. Price was increased before stock was updated.
by johnrobholmes
Jan 09, 2016 12:34 pm
Forum: Items for Sale - New
Topic: Moped Rims and Wheels, 36 hole, 16" 17" 18" 19"
Replies: 169
Views: 30727

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

Hubmotor specific 17" rims just arrived and are back in stock.
by johnrobholmes
Dec 24, 2015 12:14 pm
Forum: Items for Sale - New
Topic: Moped Rims and Wheels, 36 hole, 16" 17" 18" 19"
Replies: 169
Views: 30727

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

One of my workers, Jonathan, will be leaving us in about 6 weeks and he runs the spoke machine. I no longer have time for it and the machine is tedious to operate, so we are considering just keeping certain lengths in stock for common hub motors. If you can please list the motors you want to lace in...
by johnrobholmes
Dec 24, 2015 12:45 am
Forum: Items for Sale - New
Topic: Moped Rims and Wheels, 36 hole, 16" 17" 18" 19"
Replies: 169
Views: 30727

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

Will do. They are due about any time now.
by johnrobholmes
Nov 12, 2015 10:54 pm
Forum: E-Bike Non-hub Motor Drives
Topic: What are you guys building over the winter?
Replies: 40
Views: 3869

Re: What are you guys building over the winter?

solid axle gokart on a mini chassis powered by a hub motor, underneath a power wheels jeep body. Radio controlled so I can ride on top or use it as a golf caddy. Tow trailers, kids, adults, whatever. I used it with the stock driveline until it burned up the motors and I got sick of the gearbox whine...
by johnrobholmes
Nov 08, 2015 2:41 pm
Forum: E-Bike Technical
Topic: Definitive Tests on the Heating and Cooling of Hub Motors
Replies: 1982
Views: 255977

Re: Definitive Tests on the Heating and Cooling of Hub Motor

Upon further consideration, the fully potted motor does give some advantage over just "dipped" if we consider long term reliability as the main goal. With the delicate parts sealed , an open sidecover is much more feasible too. With the core having some improved thermal coupling to the copper it can...
by johnrobholmes
Nov 08, 2015 11:29 am
Forum: E-Bike Technical
Topic: Definitive Tests on the Heating and Cooling of Hub Motors
Replies: 1982
Views: 255977

Re: Definitive Tests on the Heating and Cooling of Hub Motor

Great test. Not too surprising that the potting doesn't make much difference since the copper is in direct contact with the iron. A thin coat of epoxy or varnish may be all that is needed to keep the windings from moving around and help a little with heat transfer between wire strands. Based on my ...
by johnrobholmes
Nov 06, 2015 11:42 am
Forum: Battery Technology
Topic: The Cycle Satiator, universal charger for the enthusiasts
Replies: 663
Views: 83853

Re: The Cycle Satiator, universal charger for the enthusiast

As long as you don't charge them cold and then bring them into a warm place, it's not a big deal to charge cold if you aren't at fast rates.
by johnrobholmes
Nov 05, 2015 11:25 am
Forum: Battery Technology
Topic: The Cycle Satiator, universal charger for the enthusiasts
Replies: 663
Views: 83853

Re: The Cycle Satiator, universal charger for the enthusiast

Update for me, charger is still the most excellent part of kit I have. Accidentally left it out in a light rain, no problems.


The only downside is that I need a lot more of them so I can hard mount them on all my rigs!
by johnrobholmes
Nov 05, 2015 9:04 am
Forum: E-Bike Technical
Topic: Definitive Tests on the Heating and Cooling of Hub Motors
Replies: 1982
Views: 255977

Re: Definitive Tests on the Heating and Cooling of Hub Motor

Why dump heat into the sidecovers? Because they are aluminum and have the largest surface area! Might as well use what is already there to sink heat. I shape the back iron on our UAV outrunner motors the same way, for the same reason of trying to get lowest weight. I'll gladly take a few of your fir...
by johnrobholmes
Nov 04, 2015 10:17 pm
Forum: Motor Technology
Topic: Asynchronous motors - is induction the new future?
Replies: 76
Views: 12801

Re: Asynchronous motors - is induction the new future?

I talked with an engineer at thingap many years ago, about using them in "traction" vehicles. His suggestion was that I look elsewhere, because of the low torque density and low thermal mass of their motors. They can go from good to smoked too fast. Fine platform for positioning and robotics use, bu...