Input sought on light, clean build

This post is both my introduction to the site and proposed build. By way of introduction, I bought a Boosted Dual+ recently, which was my first electric skateboard, to complement a train commute in the San Francisco Bay Area. I loved riding it and it really improved my commute experience, but it had two problems: (1) its 99 Wh battery didn't last through the commute and (2) its remote sometimes lost its connection with the board. So, I returned it. With its 165Wh battery, the Marbel looks perfect, on paper, but I don't trust the company to deliver or stand behind its product if it does deliver a board. So, I'm going to build my own board.

Objectives
- Carry my 155 pound self on a five-mile, one-way commute, which includes one mile-long uphill at about 10 - 12% grade
- 25 mph top speed
- capable of climbing 15% grades
- light
- clean


So, having done a lot of reading on this site, here's what I'm thinking . . .

Specifications
- Hi5ber Zenith board, for its lightness
- Carvon single hub motor, for its clean installation
- VESC
- gt2b remote with BadWolf enclosure, from Ollin, for its compactness and reliable connection
- 12S 5Ah battery, to provide enough power for climbing hills and enough range for my commute (type TBD; see below)
- psychotiller or aluminum box enclosure (TBD)


Of course, I have a few questions . . .

Questions
- Any general suggestions or comments on my proposed build?
- Would a gt2b receiver work inside an aluminum enclosure?
- Would 12S2P Samsung 25R 18650s provide enough current? I'd love to have a battery pack with a BMS for easy charging. The 12S3P pack torqueboards is now developing looks great, but it's bigger than I want. If I have to, I'll use two 6S LiPos and balance chargers, but I'd really like something cleaner and simpler because I'll have to have chargers at both my house and my office.

You could first start using Li-Poly, just to really know what max amps you will be reaching going up that hill on 12s. My guesstimate is that you "have" to use 12s3p if you are going to use 18650 cells because I think it will be over 40A.

Hey Steve!

Nice to see more SF riders in the area. I'm usually in the Financial District, North Beach, Chinatown area in downtown.

A ton of people enjoy the Boosted+ but there's so much more benefits to riding your own board. I've heard stories of the $600 main board on a boosted if you blow it out.

I've also found bluetooth to be highly unreliable in the city. I prefer the 2.4ghz controllers as they are solid. Too many people for issues and too many cars to have an eboard be unreliable.

Most smaller grade hills are about 15% inclines but the steeper hills in SF are about 20-25% inclines. Not sure if you know the street. Montgomery and Pacific seem like a 20-25% incline. It's pretty steep and most boards won't make it up there at all.

Here's a great article on the steep hills in SF - http://www.datapointed.net/2009/11/the-steeps-of-san-francisco/

I find any hill higher than about 25 or 28% incline you don't normally want to climb and/or even go down. By Coit Tower there's this one area Filbert between Leavenworth and Hyde which is 31.5% grade.

I doubt you can climb any reasonable hills with a single hub motor but would like to see it. Maybe LEVer has more opinions on that. I have yet to test but I hate being stranded.. I use my board solely to commute uphill so I've been hesitant to test the board yet.

I've also been using this 2.4ghz mini remote - http://diyelectricskateboard.com/product/torqueboards-2-4ghz-mini-remote-controller/. It's been working great and beats having to 3d print an enclosure for the GT2B. However, if you wanted to save money the GT2B would be a better option.

With the Hi5ber boards, you'll need to bolt your enclosure to the deck. I've tried using double sided tape but eventually they will come off and/or rip the clear coat off of the deck.

VESC would be a great option for the ESC.

I would highly recommend dual motors either if you go dual hub motor or dual belt drive. The added second motor may cost more money but it increases the reliability of your board a ton! It's worth the added cost.. I don't enjoy running a single motor board in SF. Flat ground is no issues run a single motor. However, you can still run a single 50mm or even 6355 setup in SF. You just have to avoid the 25% inclines and stick to 15-20% inclines. Check your motors and make sure your board is running optimal and motors/esc aren't overheating. Should be fine though. I'm a bit heavier at about 180lbs.

There is a threshold to how hot your motors an ESC will run and if you force it past that threshold you'll burn out the ESC/Motor. However, if you stop it right before and let it cool down and just walk up the last 10 steps up a hill you'll be fine. Once you get a sense of your route and how hot your setup runs then you can adjust from there. Understanding your board per your terrain and load on the board is significant especially if you are scaling hills. Flat ground is no issues.

GT2B should work perfectly fine in an aluminum enclosure. You can always stick out the antenna through the box with the motor wires for added reception but GT2B and/or most 2.4ghz setups are 100% reliable. I've gone 3k+ miles with no drop besides a dead battery I'd advise against the aluminum enclosures as they are a bit too rigid.

Good luck with the build! There's more and more guys/gals*lol running around in SF on custom boards!

The tough part there is the mile-long climb. Climbing steep-ish but short hills is somewhat easy, as long as you get a lot of momentum before going up. But going up for a mile will suck the juice out of your battery, even if it's not that steep. And as your voltage goes down, you get slower and slower, making the motor/s ask for more juice from the battery, making it have even have lesser voltage. It's a vicious cycle.

Whether it's geared or hub motors, the important thing is to have a big battery pack with high voltage and high capacity. Hub motors at 12s will get you up with a lot of speed, but will also need lots of amps. Geared motors will consume less amps, but will be slower getting up, making you consume maybe almost the same total of amps because it took you longer to get on top of the hill. And you cannot use small, high kv motors because they will probably burn up halfway through the climb. You need copper mass to manage the heat that will surely be generated. Needless to say, you will end up having a heavy board.

Thanks very much for your detailed, thoughtful replies, gents!

torqueboards said:

I've also found bluetooth to be highly unreliable in the city. I prefer the 2.4ghz controllers as they are solid. Too many people for issues and too many cars to have an eboard be unreliable.

I've also been using this 2.4ghz mini remote - http://diyelectricskateboard.com/product/torqueboards-2-4ghz-mini-remote-controller/. It's been working great and beats having to 3d print an enclosure for the GT2B. However, if you wanted to save money the GT2B would be a better option.

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I agree absolutely on the importance of reliability in the city. Your $50 mini remote is a great upgrade from the full-size GT2Bs and would be very much worth the extra cost to me. However, Ollin's looks smaller and seems to have an internal, rechargeable battery pack. Unless there's some downside to it (?), I don't mind the extra $40.

torqueboards said:

Most smaller grade hills are about 15% inclines but the steeper hills in SF are about 20-25% inclines. Not sure if you know the street. Montgomery and Pacific seem like a 20-25% incline. It's pretty steep and most boards won't make it up there at all.

I doubt you can climb any reasonable hills with a single hub motor but would like to see it. I would highly recommend dual motors either if you go dual hub motor or dual belt drive. The added second motor may cost more money but it increases the reliability of your board a ton! It's worth the added cost.. I don't enjoy running a single motor board in SF. Flat ground is no issues run a single motor. However, you can still run a single 50mm or even 6355 setup in SF. You just have to avoid the 25% inclines and stick to 15-20% inclines.

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Most of my actual city riding would be in the Mission and SOMA, so I'm willing to give up the ability to climb hills over 15% in exchange for the lightness of a single motor setup. That said, I do want to be able to get up my one-mile 10+% hill at a decent speed. With that objective in mind, would the Carvon single hub motor or this Enertion be a better choice?

torqueboards said:

With the Hi5ber boards, you'll need to bolt your enclosure to the deck. I've tried using double sided tape but eventually they will come off and/or rip the clear coat off of the deck.

I'd advise against the aluminum enclosures as they are a bit too rigid.

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Right, I understand it's fine to drill/screw to the bottom of the Hi5ber board. Would the rigidity of an aluminum enclosure be a problem even with the H5ber board? I figured the deck would be stiff enough that the stiffness of the aluminum wouldn't really be a problem, but I'd love to hear about it if I'm wrong.

torqueboards said:

There is a threshold to how hot your motors an ESC will run and if you force it past that threshold you'll burn out the ESC/Motor. However, if you stop it right before and let it cool down and just walk up the last 10 steps up a hill you'll be fine. Once you get a sense of your route and how hot your setup runs then you can adjust from there. Understanding your board per your terrain and load on the board is significant especially if you are scaling hills.

I'd advise against the aluminum enclosures as they are a bit too rigid.

Click to expand...

The specs on the VESC (per Ollin) are: "Voltage: 8V – 60V (Safe for 3S to 12S LiPo). Current: Up to 240A for a couple of seconds or about 50A continuous depending on the temperature and air circulation around the PCB." I figured an aluminum VESC enclosure or heat sink would help the VESC. Thoughts? At 12S, would I need 50A or more to get me up the hills?

Regarding the motor, I can't find sustained power or current ratings on either the Carvon or Enertion motors. Any specs on them? Would the motor or the VESC be the limiting factor?

LEVer said:

You could first start using Li-Poly, just to really know what max amps you will be reaching going up that hill on 12s. My guesstimate is that you "have" to use 12s3p if you are going to use 18650 cells because I think it will be over 40A.

Click to expand...

Understood about the batteries, thanks!

LEVer said:

The tough part there is the mile-long climb. Climbing steep-ish but short hills is somewhat easy, as long as you get a lot of momentum before going up. But going up for a mile will suck the juice out of your battery, even if it's not that steep. And as your voltage goes down, you get slower and slower, making the motor/s ask for more juice from the battery, making it have even have lesser voltage. It's a vicious cycle.

Whether it's geared or hub motors, the important thing is to have a big battery pack with high voltage and high capacity. Hub motors at 12s will get you up with a lot of speed, but will also need lots of amps. Geared motors will consume less amps, but will be slower getting up, making you consume maybe almost the same total of amps because it took you longer to get on top of the hill. And you cannot use small, high kv motors because they will probably burn up halfway through the climb. You need copper mass to manage the heat that will surely be generated. Needless to say, you will end up having a heavy board.

Click to expand...

What would be your guess about current needs with your single hub motor? The Enertion motor? What current can the motor safely use, on a sustained basis? Should I just give up on the idea of a single motor? My commute includes a ride on a (crowded) train, so I'd really like to keep it as light and clean as possible.

The GT2B is bigger than the 2.4ghz Mini which I offer. I think the BadWolf enclosure is still bigger. Mini uses (2) AA batteries but I have been using it for over 1 1/2 months now for about 1 hour/day 5 days week and still has juice left. Batteries are some cheapo batteries too.

I haven't yet ridden my hub motors uphill in the city yet so can't comment on that one. I'm sure, it would be fine if your only looking to climb 10% inclines.

If you do choose a 6374 motor it will weigh much heavier than a typical 6355. I think either works out since your 150 lbs and only need to climb 10% inclines. I'm pretty sure hub motor, 6355 would be adequate. It's only the 15-20% inclines that would require more.

I'm about 180 lbs and can climb up 10% inclines with a 50mm so there's no issues IMO.

Aluminum enclosure can break off from the flanges. Rigid isn't what you would want normally.

VESC is nice and you most likely wouldn't have to worry about the heat.

I'd suggest a 29" deck. This 29" jet deck is nice https://www.muirskate.com/longboard/decks/70513/jet-2015-spud-29-longboard-skateboard-deck-w-grip

Your looking at about a 10-12 lb board at a single motor setup. Batteries, Motors tend to be the heaviest items.

SteveS said:

...

What would be your guess about current needs with your single hub motor? The Enertion motor? What current can the motor safely use, on a sustained basis? Should I just give up on the idea of a single motor? My commute includes a ride on a (crowded) train, so I'd really like to keep it as light and clean as possible.

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I honestly think for a mile long climb, you would need dual hub motors. You need to have speed and get it over as quickly as possible. But...going double will need even bigger batteries because of having to feed more amps to the two motors.

So I would suggest a "big 63mm" motor with high kv (200-275) and geared down to safely ride a 12s pack. This will give you enough copper mass and ventilation because of the bigger size of the motor and keep your amps down because of the gearing and high voltage, while still having enough momentum to quickly go up. I believe Torqueboard's has a motor like this in the works.

The topic of going up for a mile hasn't really been discussed here before, at least not that I'm aware of. Most of the hill climbing questions are just for short distances. I saw a video of Boosted climbing a 25% grade, but that was only for a city-block.

Hi!

I think you should go with a carving wood deck with a little amount of flex for a commuting setup. It will be more comfortable than a stiff and wood is more able to take shock on the long term. Also it is easier to setup enclosure on wood deck just because carbon don't like to be drilled.

Just an opinion but to achieve light board and you requirements a single 63mm with a more torque oriented gear and a large belt could possibly be the best compromise.

Vesc and a good 10/12S setup.

However Torqueboards is probably the best yo help you as he lived SF too.

I doubt it's actually a full mile up a 10% incline. I don't know of any blocks in SF that are a mile long with no lights.

I would suggest dual motors either way. Most definitely, adds to the durability of a setup especially if your climbing uphill.

You can always add a second motor if you wanted in the future. You can start off with a single motor setup. I'm pretty sure you'll upgrade anyhow - it's too much fun not too.

I have a new 6355 230KV motor which works well going uphill. I find as LEVer mentioned that you want to go up a hill asap and with speed plus it's more fun anyways. I find a slightly higher KV rating allows you to 230-265KV allows you to catch up to speed if you happen to slow down going uphill.

I would like to see you ride a dual hub motor Let me know if they climb hills.

90mm wheels are nice in SF btw.. Ride much better than 83mm ABEC clones. If you go the belt driven route - I've heard the 80mm Kegels are nice and soft. ABEC's & ABEC clones tend to run a little firm even if the duro is 76A.

Realistically, a dual motor setup will be around 13-16 lbs depending on how much range you want.

A single motor might be about 10 to 12 lbs.

Any lighter and your riding a weak board with 5 mile range. It wouldn't be that much heavier than a boosted board and you'd have a ton more power. You can always add a handle to the board and/or use a downhill board and drag by the wheels like a luggage.

10-11 lbs board. I'm sure, you'd be fine with a single motor 6355. I'd say try that first.

Thanks, everyone, for your continued thoughtful input!

LEVer said:

The topic of going up for a mile hasn't really been discussed here before, at least not that I'm aware of. Most of the hill climbing questions are just for short distances. I saw a video of Boosted climbing a 25% grade, but that was only for a city-block.

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torqueboards said:

I doubt it's actually a full mile up a 10% incline. I don't know of any blocks in SF that are a mile long with no lights.

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I just checked the mile-long uphill. It looks like I was too conservative. The average grade is actually about 6%; the steepest part is about 15%, but that's just under 1/10th of a mile. For what it's worth, the 3.2 miles from the train to my house basically killed a full charge on the Boosted Dual+. It powered up the mile-long hill just fine, but started to slow/lose power near the top.

Do these more accurate hill specs make you gents any more or less optimistic about a 12S, single hub motor setup?

LEVer said:

So I would suggest a "big 63mm" motor with high kv (200-275) and geared down to safely ride a 12s pack. This will give you enough copper mass and ventilation because of the bigger size of the motor and keep your amps down because of the gearing and high voltage, while still having enough momentum to quickly go up. I believe Torqueboard's has a motor like this in the works.

Click to expand...

torqueboards said:

I have a new 6355 230KV motor which works well going uphill. I find as LEVer mentioned that you want to go up a hill asap and with speed plus it's more fun anyways. I find a slightly higher KV rating allows you to 230-265KV allows you to catch up to speed if you happen to slow down going uphill.

I would like to see you ride a dual hub motor Let me know if they climb hills.

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I'm still attracted to the cleanness of the hub motors, but this motor looks very impressive, especially for its price! It sounds even a single-motor setup would have no trouble with my long hill? At 2650W, with a 12S setup, it sounds like it would pull 60A at peak. Do you have a rated sustained power/current rating? What does the motor weigh?

torqueboards said:

90mm wheels are nice in SF btw..

10-11 lbs board. I'm sure, you'd be fine with a single motor 6355. I'd say try that first.

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These specs look good to me. What gear ratio would you recommend with 90 mm wheels, supposing I want a top speed of 25+ mph?

One other question: may I presume this setup's efficiency would be similar to a Boosted Dual+? So I'd get about twice the range with a 12S 5Ah (222 Wh) setup as I got with the Boosted's 99Wh battery?

I know a few people who are riding single motors but you want a 63mm motor and 15mm belts. 15mm belts work much better. They add to drag but I have no means to kick my board.

I'd say try a single motor first then go dual motor if you really need too.

I'm pretty sure you'll want dual anyways lol