Search found 3784 matches

by johnrobholmes
Jul 21 2015 12:53pm
Forum: E-Bike General Discussion
Topic: q85 sensor boards
Replies: 11
Views: 988

Re: q85 sensor boards

So they just float in air, not supported by a pcb or anything?



I will use epoxy for a fillet support from the pcb to the legs and case. I understand they do not rest on the stator, and would not want to permanently attach them into the motor since there is a nice removable pcb.
by johnrobholmes
Jul 20 2015 2:28pm
Forum: E-Bike General Discussion
Topic: q85 sensor boards
Replies: 11
Views: 988

Re: q85 sensor boards

I make motors for a living and will be machining custom one sided axles, rewiring is not a concern. Brand new motors will just cost another $500 and save no work at this point. The sensor boards are being supplied with matching 9 wire harness as well. We will be sure to epoxy the sensors to avoid mo...
by johnrobholmes
Jul 18 2015 9:11am
Forum: E-Bike General Discussion
Topic: q85 sensor boards
Replies: 11
Views: 988

Re: q85 sensor boards

Aikema responded within 15 minutes with a quote, $100 for 8 boards and harnesses with EMS shipping. Done! Cheaper than any other option. Ananda responded with a completely confused salesperson talking about pedal sensors. I did attach the motor photo with missing sensor clearly available, so I'm bet...
by johnrobholmes
Jul 16 2015 11:56pm
Forum: Items for Sale - New
Topic: Compact Field Oriented Controller, ASI + Grin, limited run
Replies: 1236
Views: 244583

Re: Compact Field Oriented Controller, ASI + Grin, limited r

Having more experience than I would like to have potting equipment, I must say that is an absolutely beautiful job! Do you have a vac chamber for degassing prior to the pour, or putting a vac on it during the pour? That is a pretty sizable hunk with no bubbles, fantastic work sir. You make me want t...
by johnrobholmes
Jul 16 2015 10:56pm
Forum: E-Bike General Discussion
Topic: q85 sensor boards
Replies: 11
Views: 988

Re: q85 sensor boards

I'm not sure who I am talking to, there is no greeting or signature on the emails from bms battery and they stopped responding after it was evident I wouldn't buy more motors or sensorless controllers to "fix" the problem. Not sure if it was an english problem, but I could never beat it into their h...
by johnrobholmes
Jul 16 2015 11:39am
Forum: E-Bike Technical
Topic: Science, Physics, Math, & Myth
Replies: 626
Views: 63107

Re: Science, Physics, Math, & Myth

My Father-in-Law used to tell me: “There are two types of people in this world: Those that can count…” (with anticipation of a conclusion that never arrived) The answer is "Those who count". Not in the mathematical sense. Way back in the 60's slot car racers used to wind their own motors. Made for ...
by johnrobholmes
Jul 16 2015 11:35am
Forum: E-Bike Technical
Topic: Science, Physics, Math, & Myth
Replies: 626
Views: 63107

Re: Science, Physics, Math, & Myth

It is pretty hard to beat the chinese old lady's who wind all day for a living. I've had them show me up before, able to fit more copper than I thought possible. That will teach me to send joke purchase orders with "Impossible" wire fill again. The trick is to make sure everything is spec'd properly...
by johnrobholmes
Jul 16 2015 11:28am
Forum: E-Bike General Discussion
Topic: q85 sensor boards
Replies: 11
Views: 988

q85 sensor boards

I ordered 6 hubmotors from bmsbattery, these guys https://bmsbattery.com/ebike-kit/178-q8512-200w-250w-12-front-driving-brushless-motor-with-12-rim-ebike-kit.html When delivered it was found they didnt send sensored versions as requested. Now they refuse to supply the sensor board and harness and in...
by johnrobholmes
Jul 07 2015 7:21am
Forum: E-Bike Technical
Topic: MXUS 3000 Hub Motor - V1 V2 V3
Replies: 1886
Views: 69481

Re: MXUS 3000 Hub Motor

I just picked up the Holmes MMP rim I ordered on the 12th. It arrived a couple days ago but I was out of town. I got the Red option rim to save $$ and I had assumed from the post he gave about them that they were new rims, but he wanted to get rid of them as red "got a lot of votes but not a lot of...
by johnrobholmes
Jul 04 2015 1:05pm
Forum: E-Bike Technical
Topic: Is my wheel going to explode?!?!
Replies: 32
Views: 2602

Re: Is my wheel going to explode?!?!

To the OP- Keep an eye on your spoke tension. The bafang flange is plenty strong for 12ga, but your rim won't allow full spoke tension without buckling. Therefore, they will work loose over time. Generally the 1000- 1500 mile mark if they are seated properly at first. If you start hearing any creaks...
by johnrobholmes
Jun 30 2015 7:28am
Forum: General Discussion
Topic: Laser Gun Project
Replies: 66
Views: 8267

Re: Laser Gun Project

Sorry I was right about the emitter failure :lol:


Sweet stuff! I just picked up a 50w CO2 laser cutter. Wish it was in the visible specktrum so I could be naughty and point it into the sky for a light show.
by johnrobholmes
Jun 19 2015 8:46am
Forum: Large EV General Discussion
Topic: Street Legal
Replies: 3
Views: 736

Re: Street Legal

All you need to do is check with your local hwy patrol or license office. Every state is different.
by johnrobholmes
Jun 15 2015 1:17pm
Forum: E-Bike Technical
Topic: 19" Motorcycle Wheels vs 26" Bicycle Wheels (rim and tires)
Replies: 2142
Views: 313634

Re: 19" Motorcycle Wheels vs 26" Bicycle Wheels (rim and tir

Thats good to hear! I've also got some wheelsets with a lot of time on them. My "old trusty" heavier mountain bike wheelset is 14 years old now, never trued it once and it still runs like the day I built it. Salsa Gordo rims, XT rear hub, Marzocchi front. I still beat those wheels often, they are mo...
by johnrobholmes
Jun 14 2015 9:21pm
Forum: E-Bike Technical
Topic: 19" Motorcycle Wheels vs 26" Bicycle Wheels (rim and tires)
Replies: 2142
Views: 313634

Re: 19" Motorcycle Wheels vs 26" Bicycle Wheels (rim and tir

I lace all of my rims to hub motors, but Holmes Hobbies and Volt Riders did my front Marzocchi hub laced to a 19x1.4 prowheel racing rim. Top notch work. I wish they still offered this service. I cant lace 3X for crap. Been considering picking up regular wheel builds again, but I have to teach a wo...
by johnrobholmes
May 31 2015 10:36am
Forum: E-Bike General Discussion
Topic: Passing people on trails who quiver in fear
Replies: 27
Views: 4968

Re: Passing people on trails who quiver in fear

bike tires will kick up sticks and rocks. On the shared trails around here they suggest that walkers turn their backs to the trail when a bike is passing. Cursing and hunching over not recommended, but maybe those folks have been slapped by sticks a few times. :lol:
by johnrobholmes
May 30 2015 11:01am
Forum: E-Bike Technical
Topic: 19" Motorcycle Wheels vs 26" Bicycle Wheels (rim and tires)
Replies: 2142
Views: 313634

Re: 19" Motorcycle Wheels vs 26" Bicycle Wheels (rim and tir

I'll finish out enough to build my wheelset to test the fitment during assembly. Price will probably be $1.50 each unanodized at first to judge demand. I should charge more because of how long they take to machine, but at the same time I don't think $2 each would be an attractive price for people. T...
by johnrobholmes
May 30 2015 9:37am
Forum: E-Bike Technical
Topic: 19" Motorcycle Wheels vs 26" Bicycle Wheels (rim and tires)
Replies: 2142
Views: 313634

Re: 19" Motorcycle Wheels vs 26" Bicycle Wheels (rim and tir

I don't see light weight anything being a good match for 20 or 30lb hub motors. But on front wheels and rear wheels with lighter motors (geared motors, 9c, BB drive, etc..) , 13/14 or straight 13ga spokes with alloy nips and drilled rims would drop serious weight. One of my workers started making a ...
by johnrobholmes
May 28 2015 10:17pm
Forum: E-Bike Technical
Topic: 19" Motorcycle Wheels vs 26" Bicycle Wheels (rim and tires)
Replies: 2142
Views: 313634

Re: 19" Motorcycle Wheels vs 26" Bicycle Wheels (rim and tir

Finally catching up around here. Stayed late to punch in the program for a nipple, it's a rough shape for now. Probably going to make the back compatible with a 1/4" driver.

Should come in around 1.3 to 1.5 grams, compared to 3.5g for a regular moped size nipple.
by johnrobholmes
May 20 2015 1:28pm
Forum: E-Bike General Discussion
Topic: spokes loosening
Replies: 32
Views: 2684

Re: spokes loosening

I carry the 13/14s with brass polyax nipples for about a buck each, maybe a few cents more than regular 14g because the blanks cost quite a bit more.
by johnrobholmes
May 17 2015 11:52am
Forum: E-Bike General Discussion
Topic: spokes loosening
Replies: 32
Views: 2684

Re: spokes loosening

Dogman, your wheels make noise because the spokes are too thick for proper tension. A balanced wheel build will never have occasions that spokes come loose enough to make noise during normal riding. The most ridden hubmotor build I have is a 30mph Puma motor in a bicycle rim with 13/14 spokes. Thous...
by johnrobholmes
May 01 2015 1:31pm
Forum: E-Bike Technical
Topic: 19" Motorcycle Wheels vs 26" Bicycle Wheels (rim and tires)
Replies: 2142
Views: 313634

Re: 19" Motorcycle Wheels vs 26" Bicycle Wheels (rim and tir

it may be a few more days before nipples, and I will only start with 14g as I haven't gotten the custom thread forms made for 13 and 12g.


Got sick yesterday and wasn't able to go into work today, so it will be monday for them nipples.
by johnrobholmes
Apr 27 2015 9:37pm
Forum: Items for Sale - New
Topic: Compact Field Oriented Controller, ASI + Grin, limited run
Replies: 1236
Views: 244583

Re: Compact Field Oriented Controller, ASI + Grin, limited r

In regards to potting and product long term value, I have also found that potting advantages far exceed the disadvantages of a less serviceable product. I generally move a few thousand new controllers per year with more than 1000 of them being potted in-house. We also pot and conformally coat an add...
by johnrobholmes
Apr 27 2015 8:53pm
Forum: E-Bike Technical
Topic: 19" Motorcycle Wheels vs 26" Bicycle Wheels (rim and tires)
Replies: 2142
Views: 313634

Re: 19" Motorcycle Wheels vs 26" Bicycle Wheels (rim and tir

So I'm going to work on making alloy nipples this week, hold me to it guys! Should drop considerable weight. I'll also eyeball making a jig to drill or mill rims into lighter specimens. That should be an "easy" 300 to 500 grams per rim. I wouldn't mind dropping a few pounds of rotational weight on m...
by johnrobholmes
Apr 18 2015 12:27am
Forum: E-Bike Technical
Topic: 19" Motorcycle Wheels vs 26" Bicycle Wheels (rim and tires)
Replies: 2142
Views: 313634

Re: 19" Motorcycle Wheels vs 26" Bicycle Wheels (rim and tir

The original plan was to drill the 1.6s out for weight concious folks, like a trials rim. I'm open to shaving weight on future batches though, absolutely.