Search found 85 matches

by Barncat
Feb 13 2021 7:21am
Forum: EBike Build Threads
Topic: 3000w Mongoose girder
Replies: 50
Views: 1874

Re: 3000w Mongoose girder

Fatty- I appreciate your cautionary observation. As stated earlier in this thread, I've already determined that #25 rear sprocket teeth are way too small to be trusted. What's REALLY dangerous is having a chain come off and lock up your back wheel at 40mph. This is why Razor makes chain guide plates...
by Barncat
Feb 12 2021 7:29pm
Forum: EBike Build Threads
Topic: 3000w Mongoose girder
Replies: 50
Views: 1874

Re: 3000w Mongoose girder

Yes that's a valid approach to connections, one that I use for thinner ga multi-wire soldered splices that'll get heat shrinked together. The vinyl tube just happened to be right for this application and you can see through it too!
by Barncat
Feb 12 2021 7:15pm
Forum: Battery Technology
Topic: Manual balance discharge device?
Replies: 24
Views: 574

Re: Manual balance discharge device?

Oh, and related to the end cell effect I've noticed that the V of those groups very quickly settles by .06-.08 volt or so as soon as it comes off the charger. Should I be governed by the the on-charger V dmm reading or the near immediate off-charger V reading as to avoiding overcharge damage? Or spl...
by Barncat
Feb 12 2021 6:55pm
Forum: Battery Technology
Topic: Manual balance discharge device?
Replies: 24
Views: 574

Re: Manual balance discharge device?

Hey amberwolf- thanks again for the prompt assistance. Unlikely I'd have found that thread on my own. So it figures that the matter at hand is not so simple given the nominal 4v supply... will study that info. This procedure would be closely monitored if I try it. In the interim I did see a recommen...
by Barncat
Feb 12 2021 2:18pm
Forum: EBike Build Threads
Topic: 3000w Mongoose girder
Replies: 50
Views: 1874

Re: 3000w Mongoose girder

Build is pretty much done and have maybe 50 miles on it thus far. A fun "toy" that'll get to very near 45mph. I suspect the cops may take a dim view of it but have not encountered any, yet. There are a lot of conventional ebikes here in FL but they can fake it with pedals. Mine are removed...
by Barncat
Feb 12 2021 1:29pm
Forum: Battery Technology
Topic: Manual balance discharge device?
Replies: 24
Views: 574

Manual balance discharge device?

Sorry for asking as this has no doubt already been addressed (can't find) but what would be the best cheap and easy resistive device to put between alligator clips to manually bleed charge off, say, a 5p 18650 cell group? I'd think 5A would certainly be a safe current draw and my Imax B6ac is limite...
by Barncat
Feb 07 2021 10:05am
Forum: Battery Technology
Topic: Negative to negative parallel short Q
Replies: 4
Views: 159

Re: Negative to negative parallel short Q

I do have a bunch of those black plastic cell holders, but as mentioned elsewhere I'm trying to reinvent the wheel with my no-weld design in testing. Cell type and pack design are all of course fraught with compromises, and they're all surprisingly dangerous. Safer, lighter, cheaper, and more energy...
by Barncat
Feb 06 2021 11:37pm
Forum: Battery Technology
Topic: Negative to negative parallel short Q
Replies: 4
Views: 159

Re: Negative to negative parallel short Q

Thanks for the explanation amberwolf. Somehow the prospect of the negative steel cans touching seemed less threatening... The common practice of gluing cells directly together sounds a bit risky then. There's a lot riding on that thin layer of plastic...
by Barncat
Feb 06 2021 6:53pm
Forum: Battery Technology
Topic: Negative to negative parallel short Q
Replies: 4
Views: 159

Negative to negative parallel short Q

Embarrassed to ask, but what happens if the cans of two 18650 etc cells in different parallel strings of a series pack short? Can't seem to find that answer through search and can't really visualize it...
by Barncat
Feb 06 2021 10:37am
Forum: EBike Troubleshooting
Topic: Are generic Chinese controllers and throttles non-adjustable?
Replies: 26
Views: 734

Re: Are generic Chinese controllers and throttles non-adjustable?

Nevermind. I see it was moved to Ebike Troubleshooting :)
by Barncat
Feb 06 2021 10:35am
Forum: EBike Troubleshooting
Topic: Are generic Chinese controllers and throttles non-adjustable?
Replies: 26
Views: 734

Re: Are generic Chinese controllers and throttles non-adjustable?

There is something to be said for switches and knobs. Just an old-fashioned analog guy...

This thread has disappeared from the Motor section of the site as far as I can tell. Not a big deal but just wonder why... there was a recent software site change apparently.
by Barncat
Feb 05 2021 11:20am
Forum: EBike Troubleshooting
Topic: Are generic Chinese controllers and throttles non-adjustable?
Replies: 26
Views: 734

Re: Are generic Chinese controllers and throttles non-adjustable?

Or you can just use your thumb, that marvelous appendage that separates us from the lesser mammals :)
by Barncat
Feb 05 2021 11:00am
Forum: EBike Build Threads
Topic: 3000w Mongoose girder
Replies: 50
Views: 1874

Re: 3000w Mongoose girder

Got back on the road for further testing. I cut out 4 polycarbonate rings, 2 @ 1/8" thick to space the larger 3/16" thick guide rings at the proper width. It works. Chain won't get thrown again. I'm waiting for some new 25H chain which is hopefully better made. I'd also recommend the freew...
by Barncat
Feb 04 2021 6:44pm
Forum: EBike Troubleshooting
Topic: Are generic Chinese controllers and throttles non-adjustable?
Replies: 26
Views: 734

Re: Are generic Chinese controllers and throttles non-adjustable?

As a follow-up, the three speed switch makes a standing start launch just fine, and once you're rolling you can of course instantly switch to either higher range. I suspect that that approach is what the controller designers intended, and I made the problem more pronounced by over volting... The pol...
by Barncat
Feb 03 2021 6:03pm
Forum: EBike Build Threads
Topic: 3000w Mongoose girder
Replies: 50
Views: 1874

Re: 3000w Mongoose girder

Yes I'm very familiar with everything you just wrote with the exception that I've never used 25H chain before. It looks more like jewelry than power transmission equipment. The stuff is plenty strong in tension for 4 or 5hp it seems. The issue is the sprocket teeth are so small that it'll throw inst...
by Barncat
Feb 03 2021 5:44pm
Forum: EBike Troubleshooting
Topic: Are generic Chinese controllers and throttles non-adjustable?
Replies: 26
Views: 734

Re: Are generic Chinese controllers and throttles non-adjustable?

Yep that's the bike. Will discuss chain on other thread. I described the problem above in this thread. Of course Fedex showed up an hour ago with a ripped empty envelope that was supposed to contain my replacement 25H chain................ I wired up an SPDT toggle to activate the controller 3 speed...
by Barncat
Feb 03 2021 10:11am
Forum: EBike Troubleshooting
Topic: Are generic Chinese controllers and throttles non-adjustable?
Replies: 26
Views: 734

Re: Are generic Chinese controllers and throttles non-adjustable?

Agreed it's time to take some measurements. For what these throttles cost I might buy a couple more and swap them out for comparison. I was not anticipating problems.... not into the cost and hassle of resistor mods of the high end pot units at present. I'm still sidelined right out if the gate from...
by Barncat
Feb 02 2021 1:40pm
Forum: EBike Troubleshooting
Topic: Are generic Chinese controllers and throttles non-adjustable?
Replies: 26
Views: 734

Re: Are generic Chinese controllers and throttles non-adjustable?

Tcat- I saw from your #1 mod that the front end dead band could be reduced as desired but still didn't see how that would reduce the "wheelie" start- (which i am getting, front wheel 3" off the ground...) The motor still switches from off to on at some very finite point in time. So it...
by Barncat
Feb 02 2021 10:25am
Forum: EBike Troubleshooting
Topic: Are generic Chinese controllers and throttles non-adjustable?
Replies: 26
Views: 734

Re: Are generic Chinese controllers and throttles non-adjustable?

Amberwolf- thanks for the extensive info. I wasn't really aware that there was much difference between hall throttles. I don't suppose any of them publish detailed specs... Will research. Looks like the pot throttles are either Magura or Domino intended more for emotorcycles. I'd prefer to avoid mes...
by Barncat
Feb 01 2021 11:02am
Forum: EBike Troubleshooting
Topic: Are generic Chinese controllers and throttles non-adjustable?
Replies: 26
Views: 734

Re: Are generic Chinese controllers and throttles non-adjustable?

I didn't really think there were any adjustment/program capabilities on these components. Not sure I'll veer off into arduino land yet amberwolf as I like to keep things simple but appreciate the suggestions. I think the pot throttle approach is what I'm looking for if I decide I can't live with the...
by Barncat
Jan 31 2021 10:26pm
Forum: EBike Troubleshooting
Topic: Are generic Chinese controllers and throttles non-adjustable?
Replies: 26
Views: 734

Re: Are generic Chinese controllers and throttles non-adjustable?

TC- coincidentally I seem to have hit the nail on the head in my original post re parabolic vs linear voltage which is exactly what you plotted for pot throttles at the end of your instructional write up. I was big into HO scale slot cars in my early teens and am craving that smooth ramp up of power...
by Barncat
Jan 31 2021 6:19pm
Forum: EBike Troubleshooting
Topic: Are generic Chinese controllers and throttles non-adjustable?
Replies: 26
Views: 734

Re: Are generic Chinese controllers and throttles non-adjustable?

TC- thanks for that very detailed link. Pretty sure I scanned some of that weeks ago out of curiosity. Will study further. It may be unclear from my previous posts but I do not believe any of my equipment is malfunctioning in any way. I suspect it's the baked in EE design and am curious if other guy...
by Barncat
Jan 31 2021 3:14pm
Forum: EBike Troubleshooting
Topic: Are generic Chinese controllers and throttles non-adjustable?
Replies: 26
Views: 734

Re: Are generic Chinese controllers and throttles non-adjustable?

My further musings: 1) I could avail myself to the 3 speed feature on the controller and add a rocker switch to the bars... sort of a half-assed clutch. Launch in low and immediately switch to hi. Initial plan was who needs lo/medium settings... 2) I could go up a tooth on the front sprocket. That w...
by Barncat
Jan 31 2021 2:13pm
Forum: EBike Troubleshooting
Topic: Are generic Chinese controllers and throttles non-adjustable?
Replies: 26
Views: 734

Re: Are generic Chinese controllers and throttles non-adjustable?

Read through the link, thanks, and will invariably do more study than I've already done. Have rudimentary knowledge of trap, sine and foc. To be more specific- I have a standard issue ebay component setup on the Mongoose girder build referenced elsewhere, with a 3000w "Kunray etc" inrunner...
by Barncat
Jan 31 2021 9:47am
Forum: EBike Troubleshooting
Topic: Are generic Chinese controllers and throttles non-adjustable?
Replies: 26
Views: 734

Are generic Chinese controllers and throttles non-adjustable?

I assume the answer is yes. I have a 5 wire Hall sensor throttle with V indicator and a 60v 55A controller. Both are ostensibly made well. The annoying thing is the instant voltage is applied from a standing start too much motor torque is generated, even with the most delicate possible twist, making...