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what to buy - a very general specific question

e-rofti

100 µW
Joined
Jan 21, 2020
Messages
9
I am on this impressive forum because of my itch to have some electric propulsion.

My plan was to import (as we have no manufacturers here) a Stealth Bomber/Vector Typhoon/EEB enduro type thing. I really want to build an interest under my fellow enduro bike riders and mountain bike riders. Range and top speed are not really important. Ease of ownership and "grunt" are. 80km/h is sufficient.

I am confused between the many battery/controller/motor options. I have spent (invested) much time researching but perhaps there are "standardised" answers.

I want a setup that is tried and tested. For instance, I cannot get stuck with a controller that is complicated to set up or that does not want to communicatte correctly with the motor or battery. Or, having a controller too weak or too strong for the other components.

My vague idea is to get a QS205 v3 (or so) motor and Sabvoton 72v200a controller. EM3EV sells a https://em3ev.com/shop/em3ev-72v-20s10p-rectangle-battery-pack-24-5ah-29-5ah/ that may be sufficient.

This person was very helpful (with a build sheet):
https://www.reddit.com/r/ebikes/comments/axhi5j/help_with_my_first_ebike_build_eeb_5000w_qs_v3/

I am happy to be pointed into a direction or to a thread.

Laugh at the new guy but I would appreciate some guidance.

Thank you.
 
Sabvoton went out of business in 2015. The old stock is supposedly good but anything made after 2015 is a knockoff. Afaik those knockoffs are usually poor quality and have a habit of going up in smoke not long into the ownership period. Ymmv there as I have no direct experience, but that seems to be the general consensus from what I've seen around here.

I'd buy a Nucular 24f personally. Asi is also well regarded. If budget is a concern there are other cheaper options as well.

I'm usually whole-heartedly against buying packs from China, but EM3EV has a solid reputation. That said pay careful attention to the cell options. They state:

"For the 25R cells this means a recommended max discharge current of approx. 100A, ~74A max discharged current for the 30Q cells and 89A for the HG2 cells. We recommend a max discharge of approx 47A for the 33G cells, 51A for the 35E and 57A for the PF cells."

So to me the only one I would even remotely consider is the 25R based pack which is a claimed 24.5AH. Now I have a QS205 4t powered Qulbix Raptor 140 with 20AH of lipo in it and in my mountainous area I can get approximately 50KM out of a charge with reasonably gentle acceleration and speeds averaging around 25KPH. The more spiritedly I ride or the more I travel uphill the shorter that range becomes. At 80KMH the pack would likely be hopelessly depleted in minutes. So really, for me, that 24.5AH would ultimately leave me wanting. I plan to add another 20AH to my pack, hopefully over the winter. Not that I'm suggesting that you go lipo, but I just want your expectations to be in check before spending thousands on a dream.
 
Thank you for your reply. It is very valuable - I did not know about Sabvoton...

Your Qulbix comparison helped, too.

It seems that I will spend thousands just to find out what it is about.

If I want power and range, I will jump on my KDX200. But the point is that the KDX has very limited use. And that is the point of going electric.
 
First of all, before you even start designing the thing, you have to decide where, how and how often you will use it.

- What % on road, what % off road?
- What are the ebike laws in your area?
- Do you think you will be able to get away riding a motorbike-with-pedals looking thing with the cops you have in your area, and do it at a stress level that is worth it?
- Would you be comfortable doing so?
- The bomber style bikes are quite bad offroad and are way too heavy to carry up stairs, or regularly put in a car, will that suit you?
- You will certainly not be admitted to any mountainbike trail centers and it will be generally difficult to find a spot where both you and mountainbikers are allowed and/or have an enjoyable experience riding together.

If you have all the answers to these questions you might be able to say if the frame is appropriate.
A lot of people I see build a bomber style frame(eeb) and then are too afraid to ride it in public(or even when they do are constantly looking over their shoulder) and start building a mtb style bike right after.
Personally I think between the Sur ron and Cyc conversions, eeb should be the last resort when picking a frame not the first.
 
Tommm said:
First of all, before you even start designing the thing, you have to decide where, how and how often you will use it.

- What % on road, what % off road?
- What are the ebike laws in your area?
- Do you think you will be able to get away riding a motorbike-with-pedals looking thing with the cops you have in your area, and do it at a stress level that is worth it?
- Would you be comfortable doing so?
- The bomber style bikes are quite bad offroad and are way too heavy to carry up stairs, or regularly put in a car, will that suit you?
- You will certainly not be admitted to any mountainbike trail centers and it will be generally difficult to find a spot where both you and mountainbikers are allowed and/or have an enjoyable experience riding together.

If you have all the answers to these questions you might be able to say if the frame is appropriate.
A lot of people I see build a bomber style frame(eeb) and then are too afraid to ride it in public(or even when they do are constantly looking over their shoulder) and start building a mtb style bike right after.
Personally I think between the Sur ron and Cyc conversions, eeb should be the last resort when picking a frame not the first.

Just throwing this out there...

My riding is split probably 60% road and multi use paths, 40% offroad.

The ebike laws in my area basically state that it requires functional pedals, there is a 500 watt limit on power and a max speed of 32kmh on flat ground without pedaling. There are other stipulations, but those are the biggies.

I initially expected to be hassled by the police, but that has not been an issue whatsoever. *knock on wood* The one and only time I've talked to a cop while on the bike was shortly after getting it. I was heading home, it got dark, and I was riding on the shoulder with no lights. Long story short, he just wanted to know how I liked the bike.

Any anxiety I may have had is pretty much gone. Ride it like a bike at bike speeds, obey the traffic laws, and enjoy the ride. Clocked like 2000km in the past 6 months, mostly in the city. Ymmv. *still knocking on wood*

Aside from the drawbacks inherent to all hub motors offroad due to the unsprung weight, which frankly I don't even notice while riding, I think my Raptor handles pretty well. No complaints here anyway. As for stairs, ride up them! Unless we're talking about dragging it upstairs into your home/office, in which case you're definitely looking at the wrong bike. Same goes for stuffing it in a car or using a regular vehicle bike rack, but really anything in it's class is going to suffer from the same issues.

I've never been denied entry to anywhere that bicycles are allowed. Trails, mtb parks, bmx tracks... Even bring it on the Skytrain and Seabus from time to time. I've heard of some overzealous park rangers in the states limiting areas to "class 1 pas only" or some such, but I have personally had zero issues. Again ymmv.

Nothing against the Surron, actually considering adding one to the stable if a good price on a used one ever comes up locally. That said they draw just as much attention as a Raptor, suffer from the same issues as far as carrying upstairs or in a vehicle, the chain drive is loud and draws attention, the pedal kit is a joke... Not really solving any problems there, though the mid drive should aid in offroad handling.

Adding a kit to an existing bike is always a viable option but by the time you add the motor, controller, find somewhere to stuff a pack of any appreciable size, it usually starts becoming pretty obvious it's an ebike at a glance. Even more so when you're doing the speed limit everywhere you go. Point being if they're illegal wherever you are it might not matter so much what bike it is if it's your speed or rate of acceleration that got their attention to begin with.

Different strokes for different folks, but I like my bike. Can't comment on the knockoff frames though.
 
HK12K said:
Different strokes for different folks, but I like my bike. Can't comment on the knockoff frames though.

That is a good rundown of your own situation, I wrote my post to help him do his own rundown. Many people don't even think of these things and jump into it.

I know the sur ron looks even more like a moto, imho it is an option for those whose laws allow them to use a higher power bike, might as well simplify the affair instead of DIY.
Cheapest one I saw was this week a $3000 X road legal version. Sad I don't exactly have a use for a 4th mid drive.

The cyc kits(~bbs02 sized) are extremely stealth and do above 4.5kw. A lot of people run it with a backpack battery.
I think we can agree that is a different world when it comes to suspicion.
Torque wise it is definitely in the same leauge, and depending on his goals with range it might fit him better.
We will only know until he presents his use case.
 
Tommm said:
HK12K said:
Different strokes for different folks, but I like my bike. Can't comment on the knockoff frames though.

That is a good rundown of your owm situation, I wrote my post to help him do his own rundown. Many people don't even think of these things and jump into it.

Amen. Was just putting it out there as my experience. Relocate me or swap out the Qulbix for something of poor quality and my entire position might change dramatically.
 
**We will only know until he presents his use case.**

South Africa is a third world country, sadly.

We have no e-bike laws. The traffic department is currently happy if it has pedals. Then it is a bicycle. There is no speed or power reference. "Looking like a motorcycle" is not a test.

My intended use will be off road, primarily. We do have a national park within 5 kilometers from our home. I can get there by riding green belts for 4 of the 5 kilometers. I do not have this confirmed, but I am "pretty sure" that if it has pedals, it is a bicycle and I will be allowed there. We mostly have real bicycles with little motors in. I think there are three Stealth e-bikes in the country. I know of 6 Sur-rons in this province. They are reasonbly cheap and there seems to be an importer, so I expect to see more of them. I have seen two Zero bikes in 10 years. So, perhaps society has still to decide how it views e-motorcycles.

I want to use it like an odd type of dirt bike and try some trials bike riding but in the neighbourhood (because it is quiet), not 60km away like with my KDX.

Although it is not my primary goal, I can probably ride the 8km to work without attracting attention. My dress code and the weight of my tools of trade will be more limiting than the mode of transport.
 
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