Help with making a fast ebike from scratch

dogman dan said:
Love it that you are at least now considering a bike that could even be legal to ride. But even my conservative opinion doesn't blanch at making a bike that is 15 mph faster than legal. My main concern is just that you can ride it safely, at it's top speed, on crappy city streets. So for most hard tail bikes, things get a bit tricky above 35 mph.

As you learn more, you will see that many ebike conversion kits allow use of either a throttle, or PAS to control the speed of the bike. So for example, with the bb you can set it up so it goes when you pedal, or you can just twist the throttle and go, your choice.

Some mid drive do make the pedals go when you throttle, but mostly those are home mad stuff, or the older stokemonkey type mid drives. None of the more modern mid drives do that, they use the clutch in the crank so you can ride the throttle without the pedals having to spin.
Click to expand...

I already ride at those speeds. Over a 200 mile ride i avg 18mph. On my good days with some head wind ill be doing 45mph bursts already. GPS clocked. So im not worried about being legal or safe or stuff like that. I know i can handle the speeds and bumps just fine. And i could care less about legality of it. If i get a ticket, ehh so what. Cops around here dont care.

Im just not gonna invest 1000s into a set up that cant go faster then what i can do with my own legs. If i cant double my speed atleast, then its not worth it to me. Thats why i want to get the marlin 7 or other mountain bike with more grippy tires and better road absorption. And ill be making my own high capacity batteries for long distance rides. A bbshd at 52v with a 25ah battery and pedal assist should give me some serious distance or great top speed at some distance being lost.
 
First of all, the motor is very quiet so no need to do anything to reduce noise. The controller is built in and quite robust. As far as speed, it will go over 30MPH on the flats bone stock. Mine goes 34MPH, GPS confirmed. How fast do you want it to go? There is a way to trick the 50KPH limit by setting a smaller wheel size, selecting KPH on your display and effectively turning your KPH into MPH readings. Still, I dont know how much faster it would go without a controller upgrade.

As far as the rear cassette, less gears are better than more as the chain alignment can get a little funky with too many gears. Since you are in a flat area, I really doubt you'd use more than three to four gears.

As far as vendors that carry all the necessary items you mentioned, I suggest Lunacycle as they have everything you are asking about.
 
I've got 48t on my BBS02 due to the chainring to chainstay clearance. I think you'll be restricted as well unless your chainstay is a longtail bike setup.

How close a 48t on a BBS02 is for a cube reaction 29er.
0462d9cb-bfab-4165-a9dc-c5144148da78.jpg


On my cyclocross 29er I have 9 speed for the gear spread (because sometimes hills frock you)... The first 3 gears have bad chain angle, but it's not too bad that you cant use them on pedal only (non assist).
 
Why not buy a frame like the one from em3ev and put a monster hub motor on it, laced to a motorcycle rim and tire (been discussed and written on). Use good downhill shocks, hydraulic brakes, quality chains (or carry a bunch of spares) and you'll be fast and safe. Its not gonna be cheap.
Or go over to non-hub section and check out a few of the cyclone 3000 builds.

Deep inside all of us, we all have our dream builds. I say you go for it, you'll be hot rodding in no time.

http://em3ev.com/store/index.php?route=product/product&path=47&product_id=209

http://kinaye-motorsports.myshopify.com/
 
Ok, so im doing a BBSHD build. And im buying a new bike to mount it on. And im looking for good recommendations

My requirements:

Dual suspension with lock outs
Hydraulic disk brakes can i can upgrade to large size disks
Would like 7 speed cassette over a 9 speed if possible
29er/700c mountain bike tires
21" frame size or similar as im 6'2".
Under $1000 if possible.

Ive really owned only treks so not sure about other brands, but i want something of good quality.
 
Can abbshd mid drive actually do 40+mph? Maybe with pedalling. I thought they were more like 30mph at 54v and 30amps.

As long as you feame and forks has disc brake mounts then you should be able to use what ever size discs you want by changing the caliper mount adapter size
 
brumbrum said:
Can abbshd mid drive actually do 40+mph? Maybe with pedalling. I thought they were more like 30mph at 54v and 30amps
Click to expand...
from my research they can do over 50mph np... just have to set them up right. I live in a very flat area and ill be building my own battery pack so i can add cells as i test everything out. Then build a final pack once i get what i like
 
Andrew Storlie said:
brumbrum said:
Can abbshd mid drive actually do 40+mph? Maybe with pedalling. I thought they were more like 30mph at 54v and 30amps
Click to expand...
from my research they can do over 50mph np... just have to set them up right. I live in a very flat area and ill be building my own battery pack so i can add cells as i test everything out. Then build a final pack once i get what i like
Click to expand...

I thought they were limited to under 60v or the mosfets blow? Oh well, what do i know anyway.

You should be able to run any size rear cassette as it does not interfere with the mounting of the middrive unit
 
brumbrum said:
Andrew Storlie said:
brumbrum said:
Can abbshd mid drive actually do 40+mph? Maybe with pedalling. I thought they were more like 30mph at 54v and 30amps
Click to expand...
from my research they can do over 50mph np... just have to set them up right. I live in a very flat area and ill be building my own battery pack so i can add cells as i test everything out. Then build a final pack once i get what i like
Click to expand...
the 7 speed cassette is so the chain isnt pulled at an angle so much. With the motor power going thru the chain, straighter the better

I thought they were limited to under 60v or the mosfets blow? Oh well, what do i know anyway.

You should be able to run any size rear cassette as it does not interfere with the mounting of the middrive unit
Click to expand...
 
52V battery with 30A continuous discharge capacity. 52t ring on the BBSHD. 11 tooth high gear on the cassette. Then you get what you get.

To make the bike faster in its own right, use smooth, high pressure tires and place the handlebars as much lower than the saddle as you can stand. Use handlebars no wider than your shoulders, and keep your knees and elbows in. Wear snug fitting clothing. Carry nothing extra. These things will allow you to make the most of whatever power you apply to the bike, whether by pedals or by motor.

I can't say you'll get to over 40mph, but you'll go as fast as the BBSHD allows you and your bike to go.
 
Im not worried about speed or power... im looking for BIKES THAT FIT AS CLOSE TO MY REQUIREMENTS AS POSSIBLE.
 
There are lots of bikes that approximately meet your criteria. They're all toys, not serious transportation. Pick any one you like; you might as well choose by paint color. Once you're looking for sub-$1000 dual suspension 29ers with hydraulic anything, you're way off in gimmick land. Nothing there is made to last, or to withstand more than its anticipated use. Choose one you think is cool. When there's no right choice, there's by extension no wrong choice either. Here's one.

No current bike such as you describe will come with 7 speed. You can put a 7 speed cassette on an 8/9 speed freehub, though. You'll need to get a 4mm spacer to put on behind the cassette. The cassette will cost you $15 to $35 and the shifter will be about $20.
 
Beat me to it Chalo. Look for bikes under $1000 used, that were sold for $2000 on up when new.

It's the strong frame that you need, not a tinfoil thin genesis or mongoose frame from walmart. At the level you want to ride at, a semi decent front shock is $700, and anything really good is way past a thou.

But you should be able to find a serviceable bike, used, in the $1000 price range. Less if you hunt enough. An old Specialized, Trek, or Giant, that sold for $1500 in 2005, or sold for 2 k in 2010. Figure on needing a new front and rear shock, so offer 500 or less. Then put what you can afford on it, with a better front shock in the plan for later.

Re the 7 speeds, you can also find or build a 7 speed freewheel type rear wheel, after you swap out the rear shifter. Front shifter you will be ditching, so that doesn't matter.
 
Plenty of trusted builders have gone 40+ mph, so the amount of watts needed is well established to be significantly over 1500W. If I was offered a huge prize to achieve a verified 40+ mph on only 1500W, I would start with a front fairing and tailsock on a DIY semi-recumbent.

60T chainrings are available, but just bolting one onto the stock BBSHD sprocket (would require precise drilling and might make chainline worse) will not automatically provide 40-MPH once you are driving g it through the wind resistance. Best of luck with whatever you try...
 
Andrew Storlie said:
Im not worried about speed or power... im looking for BIKES THAT FIT AS CLOSE TO MY REQUIREMENTS AS POSSIBLE.
Click to expand...

Something like this, perhaps? Deore stuff, mostly & RS suspension - has a 10 sprocket rear, but you could probably change that easy enough.

http://www.bikesdirect.com/products/motobecane/29er-mountain-bikes/fantom-ds2729-comp-xvi.htm
 
Good find with Bikes Direct; the components on the two bikes mentioned aren't bad, especially the Monarch rear shocks. The front forks are low end, but I've tested both (Recon Silver and XC 30) recently, and they aren't terrible.
 
Full suspension 29er are a very rare breed. You aren't finding one for less than $1k used, and anything below ~$1.5k will be beat and need significant work. A hardtail will be significantly more affordable.

Most bikes in the range you're looking at will be 9 or 10 speed simply because that's what they came with.
 
Does anyone know what the max voltage the motor itself can take? And does anone know the max torque when ran with a 72v 40A controller?
 
You must log in or register to reply here.

Similar threads

Cyb0rg d3ck3r
New Fat Tire BBSHD Build From Scratch! Need HELP Selecting Components!
Replies
16
Views
496
Bullfrog
B
G
Help and advice for a 3kw ebike build
Replies
18
Views
2,415
gursi123
G
M
First Ebike Project - Some advice needed
Replies
6
Views
905
Mordy
M
L
BBS01 commute ebike v1
2
Replies
44
Views
8,922
Lurkin
L
Back
Top