Mongoose Blackcomb

A bit of a note-to-self update for future reference. Migrating north for summer/fall and leaving the ebikes behind. They're FL toys.

I did get the new battery pack sorted out by making a couple minor refinements. I may eventually reveal the design but would prefer to make a few bucks on it...

I'll definitely replace the heavy front fork next season. Steel stanchions, stiction and unsophisticated design. Will shed 3 lbs too. Other than that the chassis is all good. It's great to have suspension even for the street.

Sadly I miscalculated on the Flipsky vesc purchase. It can't handle anything over 57ish volts, so they weren't joking. Didn't burn it up or anything but it's not cool with a 15s pack even undercharged. Another Chinese supplier Makerx-tech makes a model HI100, 75v 100A-200A max that should be perfect ( and utilize most of my battery capacity) but two weeks shipping so I'm out of time for now... so that's unfortunate and will have to relearn the vesc-tool months from now. Anybody have experience with that brand?

Anyhoo... Learned a lot about ebikes over the winter/spring, and will dial this ride in next time.

On deck- a Schwinn OCC Stingray.
 

Attachments

  • 20210427_094945_compress19.jpg
    20210427_094945_compress19.jpg
    387.6 KB · Views: 1,417
  • 20210427_094753_compress39.jpg
    20210427_094753_compress39.jpg
    382.9 KB · Views: 1,417
Barncat said:
I'll definitely replace the heavy front fork next season. Steel stanchions, stiction and unsophisticated design. Will shed 3 lbs too. Other than that the chassis is all good. It's great to have suspension even for the street.
What will you replace it with?

Barncat said:
Sadly I miscalculated on the Flipsky vesc purchase. It can't handle anything over 57ish volts, so they weren't joking. Didn't burn it up or anything but it's not cool with a 15s pack even undercharged. Another Chinese supplier Makerx-tech makes a model HI100, 75v 100A-200A max that should be perfect ( and utilize most of my battery capacity) but two weeks shipping so I'm out of time for now... so that's unfortunate and will have to relearn the vesc-tool months from now. Anybody have experience with that brand?
Yes, esk8 controllers are advertised in a confusing manner.

Maker-X: Good value but jury is out on quality (I am using a dual from them successfully ATM, though)

Prompt communication isn’t really their selling point or strong point for that matter. There have definitely been some people that have run the MakerX standard sizes and several others that have tested the stronger ones but imo it is still a pretty untested product.

Someone else might offer other opinions, but the feeling I have gotten overall is that they are decent, but don’t run them over their voltage / amp limits



You might check out the equivalent Trampa 100/250
Trampa: The best quality/bulletproof but you pay for the privilege
 
Re the fork, probably just one of those inexpensive new air forks. Have seen mixed reviews but I won't be thrashing it offroad.

Yeah, it's live and learn for me on the vesc front... I went back into the vesc tool yesterday and raised the upper voltage limit to 58.5v to cancel the flashing red led that creates a shutdown condition vs battery voltage. Even with the battery charged to 57v it still pretty easily hit an upper limit cutout with flashing red then a quick recovery. Test riding was brief and the conclusion is final. Will sell it as it's underpowered for my purposes.

Sort of begs the question: I thought it was physically impossible for a battery to generate more voltage than indicated across the terminals with a meter?

Bottom line- oversize your vesc. By a lot. I've had to leave a lot of battery power on the table thus far, but will upgrade the controller in a few months.
 
Barncat said:
Re the fork, probably just one of those inexpensive new air forks. Have seen mixed reviews but I won't be thrashing it offroad.
Yep. I have a similar build and went with an entry RockShox ZEB R. Curious what you will end up with.

Barncat said:
Yeah, it's live and learn for me on the vesc front... I went back into the vesc tool yesterday and raised the upper voltage limit to 58.5v to cancel the flashing red led that creates a shutdown condition vs battery voltage. Even with the battery charged to 57v it still pretty easily hit an upper limit cutout with flashing red then a quick recovery. Test riding was brief and the conclusion is final. Will sell it as it's underpowered for my purposes.

Sort of begs the question: I thought it was physically impossible for a battery to generate more voltage than indicated across the terminals with a meter?
Battery and distribution impedance? Discussed in the various controller build threads, but I'm not an EE.

Barncat said:
Bottom line- oversize your vesc. By a lot. I've had to leave a lot of battery power on the table thus far, but will upgrade the controller in a few months.
Aside from the confusing voltage specifications, what do you think of VESC as a platform? Features, programming, etc.
Think you'll stick with a higher-voltage VESC?
 
Hey guys- collective answer.

From what I've gathered you can run into a wattage choke point even with a vesc that's nominally in amp range for your build. So I'll probably go with a makerx HI200 unless I hear bad reviews in next few months. They did respond next day to an email inquiry.

I like the platform because it's tiny and practically weightless, programmable- especially for throttle, and seems to work great sensorless- which is one less hard-to-repair system to fail. I'm no EE or computer guy so it's somewhat difficult but I'm managing...
 
Barncat said:
From what I've gathered you can run into a wattage choke point even with a vesc that's nominally in amp range for your build. So I'll probably go with a makerx HI200 unless I hear bad reviews in next few months. They did respond next day to an email inquiry.
Just be advised that while they're both 100V max, the HI200 is recommended for 20s and 200A continuous/300A max, whereas the Trampa 100/250 is recommended for 22s and 200-250A continuous/400A burst. So you might get more out of the Trampa, although the incremental value is poor.

Barncat said:
I like the platform because it's tiny and practically weightless, programmable- especially for throttle, and seems to work great sensorless- which is one less hard-to-repair system to fail. I'm no EE or computer guy so it's somewhat difficult but I'm managing...
Good info, thanks.
Will it work sensored at low speed and then transition to FOC as well?
 
The HI200 should allow me to wring everything out of the 15s 225A battery and that outrunner.

IDK about the last question. I guess most of these units work either way...
 
Loving this. Especially the rc motor drive. I'm playing with rc motor type drives and loving the power to weight. Been considering that motors but... $$$. Also just bought 120 of the same cells as you!

The hi200 should give you all the power you want, but to get it you might need to bolt it to a large piece of metal.

The VESC and maker x things use the same FETs etc, the ratings are marketing/test condition. Videos of vedder testing suggests he places them on a table ostensibly with no heatsink, but the table is a large slab of aluminium. You can make the difference of 3x the current easily by different amounts of air flow and heatsink.

VESCs get rated by the MOSFET Vds, which is 60V for 6.6 and 100V for 100/250 and hi200 you need headroom on your battery. 60V FET is only really safe for 12s and 100V FET with 20s. 22s on the VESC 100250 sounds optimistic. 7V headroom at full charge.

Got some videos on it it action?
 
mxlemming said:
The VESC and maker x things use the same FETs etc, the ratings are marketing/test condition.

Do you have a source for this? I haven't seen a comparison, and there's generally a cost/quality tradeoff when comparing first-party components from the Western world (Trampa) versus mainland Chinese (Maker-X) clones.
 
fatty said:
mxlemming said:
The VESC and maker x things use the same FETs etc, the ratings are marketing/test condition.

Do you have a source for this? I haven't seen a comparison, and there's generally a cost/quality tradeoff when comparing first-party components from the Western world (Trampa) versus mainland Chinese (Maker-X) clones.

The maker x states the type of FETs used. They're direct FET 7769. The schematic for the vesc 75300 is public and uses 7759. The 100250 had identical case and wire in outs, though it's known from the firmware to have low side shunts... I was paid to make a 100V VESC so spent ages trying to find out. Best i came up with was a Russian forum with a pic surrounded by words saying 100250 that had direct FET.

I'm making some assumption here. But vedder uses direct FET for everything else so...

In terms of current carrying, i don't think anything other than the FETs and shunts really make a difference.
 
mxlemming said:
The maker x states the type of FETs used. They're direct FET 7769. The schematic for the vesc 75300 is public and uses 7759. The 100250 had identical case and wire in outs, though it's known from the firmware to have low side shunts... I was paid to make a 100V VESC so spent ages trying to find out. Best i came up with was a Russian forum with a pic surrounded by words saying 100250 that had direct FET.

I'm making some assumption here. But vedder uses direct FET for everything else so...

In terms of current carrying, i don't think anything other than the FETs and shunts really make a difference.

:thumb:
Thanks!
 
Hey mx- thanks for all that additional info. I've not checked in on my thread for a month...

On paper that T-motor should really perform. Got a great deal on it. It'll be months tho til I'm back at the FL place to bolt on an HI200. Will beef up the heatsink as you suggested. Will get a video clip then when it's all sorted.
 
Took about a month but the shiny new HI200 arrived a couple days ago. Feels like a beefy unit. Has 8ga phase wires, and includes the necessary small auxiliary wire harnesses. Will refamiliarize with the vesc program and hope the 25H chain can handle the job when I get this installed and sorted...

My OCC Stingray build is nearly finished so I'll get back on the Blackcomb shortly.
 

Attachments

  • 20211220_081700.jpg
    20211220_081700.jpg
    3.4 MB · Views: 863
I'm looking over the new HI200 vesc and just assumed it would have an on/off/kill switch like the Flipsky unit I started out with. No switch was included, and I see no dedicated port for one which is surprising. Seems hard to believe that the unit is supposed to be always-on... plus no emergency kill... Unless that PPM 3-pin port can be used as a switch (5v, gnd, signal)? Don't know... Could put a toggle on the +5v throttle wire but vesc would still be on I believe. Don't really want to resort to a heavy duty battery disconnect switch as an emergency kill. Hard to reach fast.
 

Attachments

  • 20211228_122100.jpg
    20211228_122100.jpg
    4.6 MB · Views: 801
I'm looking over the new HI200 vesc and just assumed it would have an on/off/kill switch like the Flipsky unit I started out with. No switch was included...
I was shocked to read this so I did some looking around.

There was a discussion over on a VESC thread where there were some posts about having an enable switch. The technical discussion was a bit over my head and from what I did understand from the posts I thought their reasoning was totally asinine.

In one constructive comment, someone pointed out that:
FYI there is an enable switch on the buck regulator of the drv8301 that you could break out to a 2 pin connector to achieve this functionality
I'm going to guess this would be an undesirable solution to hack your board, but if you can find that chip you might be able to get it to work. I'm sure this is small comfort but the open source VESC board over here does have a pin set up to switch the board on through the DRV8301.

Sorry about the bad news.
 
owhite said:
I'm looking over the new HI200 vesc and just assumed it would have an on/off/kill switch like the Flipsky unit I started out with. No switch was included...
I was shocked to read this so I did some looking around.

There was a discussion over on a VESC thread where there were some posts about having an enable switch. The technical discussion was a bit over my head and from what I did understand from the posts I thought their reasoning was totally asinine.

In one constructive comment, someone pointed out that:
FYI there is an enable switch on the buck regulator of the drv8301 that you could break out to a 2 pin connector to achieve this functionality
I'm going to guess this would be an undesirable solution to hack your board, but if you can find that chip you might be able to get it to work. I'm sure this is small comfort but the open source VESC board over here does have a pin set up to switch the board on through the DRV8301.

Sorry about the bad news.

There's no DRV but there is an lm5161

Unfortunately the two pins soldered together on the outside of the board are the Vin and enable pins and will be quite hard to break out individually.

I built a VESC based controller and broke out the enable pins, definitely worth it. When I turn it off the power consumption drops to about 0.3W.

Would still flatten most batteries in a few months though. I'd still want to have a physical disconnect for peace of mind.
 
hey guys- thanks for the help and suggestions. i have very little experience soldering tiny pcb components so best for me to avoid that route. as a motorcycle guy i know i can always grab the clutch to decouple the motor, and/or kill switch in an emergency in addition to the brakes, so some similar safety function is of course necessary on an ebike. indeed they must be legally equipped with a kill switch which makes perfect sense, though my bikes are already totally illegal w/o pedals and way over the 750W 20mph limit...

my main concern would be a malfunctioning throttle, so as mentioned in this case i'll just splice in a toggle on the hot wire. i've been riding these cheapo 3 wire throttles around for about 1500 miles thus far with (knock on wood) zero issues... but... while we're on the topic- what other main failure modes could cause the motor to spin up uncontrollably through a powered vesc?

i see maker-x sells an anti spark kill switch that plugs between xt60 battery connectors, but it's only rated for 12s and i'm at 15s 225A with this build. guess i'll chalk the lack of a switch up to "they didn't tell you that in the brochure".

will sensitive vesc circuitry be compromised over time by just slamming the thing off/on with an aforementioned heavy duty battery disconnect? no different than unplugging/plugging to charge the pack... i'll use anti spark XT90's but that function seems to fail in short order. if the caps haven't leaked down too much between rides there's very little e-shock, so a fair amount of the time wouldn't be an issue i believe.
 
The anti spark is a pain. I've got 5x20 ohm resistors parallel on an xt30 as a précharge for 20s. It works with 2x470uF, but 3 parallel but the dust pretty quick. Xt90 anti spark lasted about 10 plugs before dieing.

The caps will completely leak down in about 5 seconds so every plug in will be a big hit.

If your cables have a lot of inductance it can be an issue but with 15s and a20s capable controller it's probably ok to just hard swap the connectors. I've found the connectors last surprisingly long doing this.

Throttle failure also a pain. I prefer rcpwm throttle because it fails in an easily detectable way. Analog throttle is ok if you lose 5v or signal cable but if you lose ground it can pull high. Make sure the ground cable is solid and well crimped i guess.

VESC has a safe start, it requires a time with zero throttle to arm, so you don't plug it in and have it zoom away.

Check the hi200 actually does pull the throttle low, some VESC boards have pull downs, others the ADC inputs float.
 
mx- you've confirmed my experience that XT90 anti-sparks are just a gimmick... with a DIY 5 x 20ohm setup do they go on the plus or minus cable or does it matter? sounds like the wear item is the connector then, i was more concerned about the vesc circuitry but perhaps the caps take almost all the hot plug hit (which is what they're designed for)? the HI200 is rated to just 16s btw.

i only have experience with these basic ebike throttles so will stick with that for now. i solder all wire connections/splices where applicable. this vesc uses what appear to be the smallest JST connectors and wire, which i'm not thrilled about, so the ground is only as good as that.

will get back on rewiring and programming the bike soon.
 
Anti spark on the positive.

Careful not to run it without the main wire plugged in.

Use more resistors. 5 is the minimum that didn't die for me. Or get one big fat resistor like one of those 10W chassis mount ones.

I thought there was a 20s version of the hi200. My bad.
 
So perhaps the schematic pictured below? Similar diagram elsewhere on site. Plug the parallel side chain in first then the xt90's. I believe that then renders the big resistor mostly moot in terms of wasting energy as heat during use? Still debating the bulky disconnect switch but can't think of any other easy emergency shut off.
 

Attachments

  • 20211231_102229.jpg
    20211231_102229.jpg
    2.1 MB · Views: 695
owhite said:
Search on "150A solid state relay". Here's an example.

I'm not sure this is a good idea. These are usually triac based, they switch off at zero current. They work for AC... Not DC.
 
Back
Top