Electric Enduro Ebike questions.

[Battosaii]

Hey guys this is my first Ebike build and I had a few questions for the experts here.

First let me say this is my first ebike but I'm no stranger to building electric vehicles. I build and ride custom electric skateboards. My current build is a bit crazy for esk8 and I wanted my first ebike to be just as crazy.12s8p Samsung 30q battery, 4× 6374 190kv motors, 55mph top speed.

As for my ebike here is what I ordered so far
- EEB frame in white
- EEB battery box large
- EEB kick stand
- DNM USD-8 ebike version
- DNM Burner 2 rear shock with 850lb spring
- custom front 19" moto wheel with a dual brake disk hub
- Sram handbags
- sram stem
- black generic crank set
- black 42t crank pulley
- cnc pedals

I know I need a lot more. I'm on on the look out for tektro Augira twin+ e745 brakes for the front but haven't been able to find them yet for sale.

I also build batteries so I will be building this battery also. I want the biggest that will fit in the box.

My main question is I want a QS273 motor for my build what motor controller do you reccomend I was looking at the Savaton 72200 but is there something better out there? If I'm going to build a bike it has to be faster than my esk8.

 

[MadRhino]

It is easy to make it faster, not easy at all to make it a good ride at high speed. The combination of bad suspension design and overweight motor is making a bucking tail. Small bumps in a turn will be enough to make it very dangerous in cornering. So you will have to rebuild the suspension design, and accommodate a big motorcycle shock to make it just OK, yet far from best.

A fast motorization is only one step into building a fast bike. A bike can only be as fast as the speed that you can ride it in control.

 

[Battosaii]

It is easy to make it faster, not easy at all to make it a good ride at high speed. The combination of bad suspension design and overweight motor is making a bucking tail. Small bumps in a turn will be enough to make it very dangerous in cornering. So you will have to rebuild the suspension design, and accommodate a big motorcycle shock to make it just OK, yet far from best.

A fast motorization is only one step into building a fast bike. A bike can only be as fast as the speed that you can ride it in control.

Thank you for your insight. Is there another ppwerful motor you may reccomend for this chassis?

Edit: I ride 90% on the street so offroad ability isn't my highest priority.

 

[MadRhino]

Step down your motor choice. A QS205h50v3 in a fast winding is more than enough for speed, and not too heavy to tune a high end bicycle shock.

You will still be handicaped by the frame design and weight, but you won’t have problems riding it faster than your previous build. You still need to mod the swingarm suspension design and mounting hardware, that will be your most important task into making it able to speed safely.

 

[Battosaii]

Step down your motor choice. A QS205h50v3 in a fast winding is more than enough for speed, and not too heavy to tune a high end bicycle shock.

You will still be handicaped by the frame design and weight, but you won’t have problems riding it faster than your previous build. You still need to mod the swingarm suspension design and mounting hardware, that will be your most important task into making it able to speed safely.

Thanks, the qs205 is much cheaper too lol

This build is for occasional commute and group rides.
I was looking into possibly a high powered mid drive too. I saw Luna cycle has a 3kw mid drive kit looks like I'd need to mod the frame to make it work.

 

[MadRhino]

My QS205h50 sees bursts of 25kw in acceleration everyday. You think a 3kw mid drive can compete? Mount a QS205 as a left side mid drive with a motorcycle chain, or snowmobile belt CVT, if you need gearing down.
As a hub build it does 70 mph easy, and that is not the fastest winding.

 

[Battosaii]

Nice, that makes me feel good about getting a qs205. Worse case I can always upgrade.

Do you have a build thread? I want to see your set up if you dont mind sharing.

 

[MadRhino]

Gone in the forum rebuild, long ago. But it wouldn’t help you build an EEB frame. I build on old school DH bikes, for frame stiffness, light weight, and suspension quality.

Dirt bike. Santa Cruz V10 MK1. X5404 motor in 26’’ Sun Double Track rim. 20+ kw peak. 50 mph top speed. 86 lbs with 1.5 kw/h RC lipo. 8 years of hard riding MTB seasons, and dirty street winters. 35000 miles. Dozens of crashes.

 

[markz]

Them V10's look beefy, but no triangle space for a decent sized battery. Wonder if anyones cut one up yet. I know theres a few other builds with cut up triangles to fit big battery.

 

[Jonno]

Don't bother with the sabvoton get a nucular 24F controller

 

[MadRhino]

Them V10's look beefy, but no triangle space for a decent sized battery. Wonder if anyones cut one up yet. I know theres a few other builds with cut up triangles to fit big battery.

It has 24s 16 A/h of graphene lipo on the pic, another 8 A/h goes under the down tube when needed. I am not gonna cut a frame that I have purchased new with a lifetime crash guarantee. No one ever did that to a V10. Those with such triangle ideas buy a box frame or cut a cheap DH. And, I use my 3 battery bags modular system on all of my bikes. One front bag, one top tube bag, one down tube bag... and a SHOCK in the triangle where it belongs. :wink:

 

[markz]

Makes sense, I remember seeing just a V10 frame for a hundred or two bucks awhile ago. If I wanted a DH frame I would have gotten it.


Here are some frames people have cut up, they look cheap frames though.
https://endless-sphere.com/forums/viewtopic.php?f=6&t=235&hilit=frame+cut+battery+box&start=575#p339717
https://endless-sphere.com/forums/viewtopic.php?f=6&t=235&hilit=frame+cut+battery+box&start=450#p252774

This one DB just placed batteries wherever he could
https://endless-sphere.com/forums/viewtopic.php?f=6&t=235&p=85423&hilit=frame+cut+battery+box#p86227

 

[2WheelsMovesTheSoul]

I also build batteries so I will be building this battery also. I want the biggest that will fit in the box.

Largest pack I could fit was a 20s28p.

 

[markz]

20s28p.

I think you needed more :wink:

 

[Battosaii]

I also build batteries so I will be building this battery also. I want the biggest that will fit in the box.

Largest pack I could fit was a 20s28p.

Oh wow hahaha might not go that big but I was looking into a 24s15p with 30q cells it should allow me to pull 200a comfortably.

 

[2WheelsMovesTheSoul]

I could have gone with more in series but when I orginally built the bike, 72v was about the highest v in a reasonably priced controller. Now with PV and Nuc supporting 120v+, I wish I had more v but the range is nice.

Charge on Sunday, commute to work all 5 days, plus a spirited blast thru the local hike/bike trail on Saturday morning.

Or I can let the 205 eat 300a and drain the whole 55lb battery in under 1 hour.

 

[John in CR]

...You still need to mod the swingarm suspension design and mounting hardware, that will be your most important task into making it able to speed safely.

MadRhino,
If you wanted to have one modified, what specific changes would you want made?

 

[MadRhino]

...You still need to mod the swingarm suspension design and mounting hardware, that will be your most important task into making it able to speed safely.

MadRhino,
If you wanted to have one modified, what specific changes would you want made?
EEB raw frame.JPG

First it does need a strong swing arm pivot on bearings. I would want the pivot higher above the BB (that I can only guess on the pic).

Then a shock mounting bracket that brings the shock orientation more horizontal, let’s say you want it to push in the direction of the steer tube instead if your spine.

And, the suspension travel ratio need to be 1.2 to 1.5, meaning lifting the wheel 4 1/2 inch does push the shock 3 inch at least. This is required to obtain a proper rebound control with a heavy wheel.

I would mod some more on this frame: I would want to have some variable geometry setting points, including 2 inch 3 positions adjustable dropout height, eccentric BB, and 2 inch head tube with complete angle set headset.

That is about it, until I ride and feel it cornering. But geometry setting should be enough to tune it for any preferences.

 

[efMX Trials Electric Freeride]

should have gotten a raptor clone instead of a vector clone?.. URT suspension is crap off-road bc your standing on the swingarm unsprung.. or futr beta concentric

 

[MadRhino]

should have gotten a raptor clone instead of a vector clone?.. URT suspension is crap off-road bc your standing on the swingarm unsprung.. or futr beta concentric

Only after reading you I saw the BB on the pic, on the swing arm instead of the frame. :?

I believe that a new BB shell must be welded on the frame, and the one that is on the swing arm ignored or used for some other purpose when building the bike.

 

[Battosaii]

Maybe I should have gotten a vector mid drive chassis then.

This is my first ebike I'm sure I will learn the hard way everything you guys are telling me lol. I'll ride this for now since it's what I have and my next build will work on all the weaknesses i find.

 

[litespeed]

Just build and ride the bike as is. I come from a lot of experience in long travel off road cars and have this frame. Is it the best, absolutely not! It works well though with a QS205 V3 motor. Do I recommend jumping.....no! As long as the back wheel isn’t coming of the ground the bike works well ( a good shock is needed! Stay away from DMN!) for what it was intended for. It’s a inexpensive design that gives good battery volume/space, good strong drop outs, easy to work on, some rear shock length mounting options (you will want a 3” or longer good shock!) and still provide a somewhat level of normal peddling ability. Make sure you give yourself plenty of “sag” in the 10+ inches of travel available for the rear. I sit about 3 to 3.5 inches in. Makes it feel like a magic carpet ride. All suspensions for comfort/off road should be set up to be as soft as possible while firm enough to resist your biggest impact. My bike isn’t the one I would choose to jump with so it’s set up for what it’s designed for....Cadillac ride on the rough stuff. It rides very well AS LONG AS the tire stays on the ground.

Don’t dwell on the “would of, should of or could of” scenario just build and know what “realistically” the bike is made for. I agree that the QS205 V3 is the motor you want for this bike. It will give the bike a much better balance than the 273 on the rear end. I have a 20s15p battery in mine which gives the bike in my opinion a decent balanced feel. I however only peak in the 14.5 KW range. My biggest recommendation is that you run at least a 3 inch wide motorcycle tire and would recommend a 3.5 if you can get one. That motorcycle tire will mask the weight of the hub motor while going over curbs, rough pavement/ground better than any shock design/layout will ever think of doing. There isn’t much that is going to control 30 to 50 lbs on the end of a 22 inch stick better than a soft impact.

Looking forward to hearing how this turns out.

Tom