amped kit questions..

Hey guys.. i am new to all this and have been researching this stuff for days now.
So please mind the newbie questions..

I'm looking at getting the amped bikes 350-400watt kit and run it at the stock 36v.

I'm wondering what's involved in getting 36v dewalt lithium batteries working with these? anything special? Thinking about using two in parallel since my range needs are very low. I am 230lb.

Are these reliable?

Do they freewheel well?

And is an aluminum frame a TOTAL no no, even with torque arms?

Thanks in advance

-David

With such little power, torque arms shouldn't be really needed...

I've got 3 such similar builds based on another vendors similar hub motors in 26" and 20" varieties... I run modified controller at 25A/50A and normally 15-18S Lipo (55-66v nominal) without torque arms and notice ZERO movement.

Can't help with the Dewalt stuff, sorry.

-Mike

mwkeefer said:

With such little power, torque arms shouldn't be really needed...

I've got 3 such similar builds based on another vendors similar hub motors in 26" and 20" varieties... I run modified controller at 25A/50A and normally 15-18S Lipo (55-66v nominal) without torque arms and notice ZERO movement.

Can't help with the Dewalt stuff, sorry.
-Mike

Click to expand...

Hm.. but do you have aluminum frames on any of those bikes? you mention 20" and 26", that's why i ask. I have 700c wheels on a light hybrid bike.

The only reason i say that is because amped's page says specifically to not use them with aluminum, but doesn't say anything about using aluminum + torque arms with the lower powered kit. Then again i have ridden on a 350watt kit on an ultra light weight carbon bike, so i don't know what to believe.

The bikes are:
2010 26" dahon Jack rear - aluminum dropouts
2009.5 20" down tube nova - rear aluminum dropout mount
2009.5 20" downtube 8fh - front sus fork aluminum mount

so they are all aluminum, properly installed with inner and litter washers and torqued down tight - no issues in your power range!

The biggest reason why e-bike companies say no aluminum is because many don't include the proper washers and so when you torque them down it causes the axle lands to spread and crack the dropout or fork. The also don't want the liability.

Hope it helps!
Mike

Oooh. Nice. I like hearing that.

Okay, so instead of torque arms, you've used washers? that's interesting. i wonder if polyethylene bushings would help at all? like motor mounts on a race car.

Thanks for the advice. I've been obsessed with getting an EV bike since i first heard of them a year ago and i'm glad i don't have to give up my diamondback insight1. Not a fan of mountain bikes; maybe for a high performance bike..

On the poly anything bushings, DON'T DO IT!

Those would allow some play in the axle within the dropout, resulting in spreading and / or cracking due to twisting under motor torque... they will be fine without anything but the pair of washers per side - one inside, one outside... this ensures a proper clamp on the "beefy" section of the drop out...

Take a look at how and where the stock quick release axle hits the inside of the dropout, see the flanged area on the axle and the beefy almost notched in a circular pattern (for true flatness I believe) collar (or whatever you want to call it)?

That's where you want the inside washer to sit - as close to perfectly within the circle as you can to distribute the force evenly...

Then the flat on the axle (a part which is intended to stop the inside washer from traveling up the axle any further) will position the inside washer properly (depending on freewheel size) and when you place the outter washer and finally the nut and torque it down... well at the power levels from these motors, it will suffice.

But do not attempt to insert dampening materials... it will lead to disaster every time.


I should add that this is for rears, fronts are a different animal... they have "mini chinese torque arms" which are just washers with protrusion to wedge into the dropout space on the front fork... Same rules apply really at these power levels but upon examination you will understand the subtle difference between a front and a rear install.

-Mike

Advice taken. I'll forget about the rubber thing then. There is actually a good flat surface for the inner/outer washers anyway. My front fork actually looks fully formed as one piece, and the rear looks like a welded on piece, but they look equally as sturdy so i think i'll make this a front bike

Aluminum comes in many different grades, and the guy that made your front fork may have been hung over on a Monday when he was heat-treating a batch. They may have been behind schedule, and the Chinese supervisor decided to push one batch through too fast, because, after all...its just going to some of those snooty westerners.

Either way, whats the cost to you if a front drop-out breaks? (assuming the breakage doesn't involve an actual bike crash). With only one drop-out working on one side, perhaps the axle will spin, pulling the wires out by the roots (its happened to several posters)

You'd have to buy another fork. And if its ordered, you'd have to wait for delivery, and also hope they sent you the right one.

My advice? even at low-power, use the C-washers from ebikes.ca (if your fork has lawyer-lips) and two torque arms. If anything burns out a few years down the road...the torque arms (they are cheap) will last a lifetime and can be transferred to the next frame. Just a thought...

neptronix said:

Are these reliable?

Do they freewheel well?

And is an aluminum frame a TOTAL no no, even with torque arms?

Click to expand...

I have a rear geared kit. I've put around 400 miles on it so far. It's great, no problems. 20-21mph on 36v 20ah thunder sky lifepo4's, range of about 30 miles on half the pack, nice torque up hills. Freewheels just fine.

I have a giant suede aluminum frame, and used the amped torque arm on then rear.

I would recommend this kit.

^-- thanks, maybe i'll do that, washers + torque arms.

Good lord, that 20ah thundersky battery is cheap. But i'd need 3 of them to make 36v and that's way more voltage than i want.

What's involved in linking up lithiums to the amped kit anyway? just plug the batteries in? how do you monitor their charge, prevent them from dropping below the voltage they like, etc..

The kit comes with a battery pig tail. I cut off the spade connectors and used anderson power poles so I can put a watt meter in line. Then ring lugs to connect the power lines to the thundersky's. I have been using cell log 8 monitors to detect low cells, but am close to getting a bms system.

Why do you think 36v is too much battery?

From the Ampedbikes FAQ:

"Aluminum forks?

You cannot use aluminum forks with ANY electric hub kit. Aluminum forks are "cast" aluminum at the dropouts and are not malleable (they will not give) the twist force generated by the axle WILL break them . Its a simple test. If a magnet sticks to your forks you are ok. Steel, Chrome molly etc are malleable and can take the stresses at the dropouts. aluminum forks are primarily cast at the dropout points and are not malleable at all and unfortunately will break. I learned this the hard way by ruining a set of $700 suspension forks.

Aluminum frames?

Aluminum frames are predominantly standard aluminum and not "cast" aluminum and should be fine."

yopappamon said:

Why do you think 36v is too much battery?

Click to expand...

I'm sorry, i meant 60AH is more than i want.

per studebiker;

Does that mean that a rear one is acceptable, but a front isn't, on an aluminum bike?

Here's what my rear dropout looks like BTW..




Here's my bike: http://www.thebikestand.com/diamondback-performance-hybrid.html

It seems like the derailleur takes up some of the space and it's integrated into the frame.
Argh. Maybe this bike is not suitable

I could probably just find a steel fork for the front and use that, correct?

Are front forks commonly interchangeable, anyway?

You should be able to use a rear motor on your AL frame. Especially on the lower power gear kits from Amped. The controller is set @ 14A. The Watt meter peaks at a little over 500w. Your rear drop out looks beefy enough for that kind of power. If you are still weary, you could add a torque arm to the rear, but that is overkill on that set up IMHO.

StudEbiker said:

You should be able to use a rear motor on your AL frame. Especially on the lower power gear kits from Amped. The controller is set @ 14A. The Watt meter peaks at a little over 500w. Your rear drop out looks beefy enough for that kind of power. If you are still weary, you could add a torque arm to the rear, but that is overkill on that set up IMHO.

Click to expand...

Oh, i didn't know it was 14a. That's pretty low.
I think i'll do this with rear torque arms, or washers as someone else suggested, just as cheap insurance.

Wanted to avoid going rear motor but that definitely beats switching bikes. I prefer this bike style, and it will look stealth anyway

Thank you all. Maybe i'll go bug some folks via PM or poke around since the DeWalt to amped kit controller question still hangs in the balance.

The rear kit is a fairly simple install. It comes with two torque washers. Why would you rather have a front? With rear you could easily keep your front suspension.

Flat tires. They happen often on these skinny wheels unfortunately ( maybe the tires that came with the bike just suck though ). Just didn't want to connect/disconnect the rear wiring every time. And i was thinking weight balance would be a little better too.

Rear should be fine though. And better for stealth wiring anyway.