Safe's Electric Bike Project #001

[Link]

I see your gears, and raise you a sepex motor. 8)

Also about 100kW if I can get away with it.

If you haven't already, start a thread for this project you keep hinting at. Is it in the motorcycle area?

I intend to once I get the S-Go rolling again. The first part is working out what's what with this sepex controller I have.

Though, the real issue is ever and always money. Given that I'm not even a legal adult, I make okay money, but it's definitely not like I can just go out and pick a donor frame and get the thing working within a week.

I hate being borderline poor...:?


And who was arguing that multiple gears aren't better than one?

 

[johnrobholmes]

Conductive paste really makes the solderless tubes work well. I end to end solder my high drain Nimh packs. Takes a big iron and some practice, but makes solid packs. The only problem is taking out bad cells, you can rip the cell jacket trying to break cells out.

 

[Toorbough ULL-Zeveigh]

The issue seems to be the amount of current being drawn.

RC applications typically draw huge current in bursts. That is really bad for touch connections. But, drawing a relatively small amount of current will allow pressure connections to work.

But RC is the arena that 'safe' keeps pointing to as being smarter than us & I'm unable to locate his alternate reality on the web.
It's only when comparing contacts using Ag to Sn/Pb that there's any benefit, it has nothing to do that's the result of being in tubes.
Use silver battery bars & that variable is zeroed.
While there are a few kindred spirits like 'safe' that are attempting to put a new spin on an old idea of using tubes by compensating with silver paste they hardly constitute a crowd.

No, the vast majority of the smart RC crowd is absolutely anti-shotgun pack & they operate in exactly the same 30-40 amp territory as us which is why RC packs (even shotgun style) work right off-the-shelf on an ebike.
I really can't believe, would RC'ers embrace a technique using tubes & springs that both eats into precious real-estate that's in short supply on a model and adds a whole bunch of extra dead weight they need to haul around unnecessarily??
Which is why I find suspect safe's assertion that there's this great movement afoot, he definitely has a strange interpretation of reality.

Anyway, if it works, it works.

There are benefits and drawbacks to everything.

That's my belief as well, as I said, you can't argue with results.
If Optibike is able to convince people to part with the same amount of money for a bike that will buy you a car then all the power to them.
However I'm not the one that's saying that my way is the best way, therefore should be the only way & if you're not doing the same you must be mentally deficient.

 

[recumpence]

For what an Optibike costs, it should be freaking PERFECT in my opinion.

Don't get me wrong, I love that bike. But, C'mon, nine grand? That's insane. For that amount of money you could hire a machineshop to make anything you want in a bike and afford the highest end lipos and charger, motor, controller, etc.

Heck, I paid nine grand for my bike, and all my machining equipment to make everything I made!

Someone is making some money off that thing.

Matt

 

[safe]

Solderless Tubes "accept" Murphy's Law

From what I can tell you don't get an advantage either the old way or the solderless way as far as conductivity. The pack is going to deliver energy within a 1% difference whether you go with all the soldering or if you use tubes. What makes the Solderless Tubes "smart" is that you don't have to worry about problems as they crop up. If a cell goes bad it's pretty easy to find it and replace it. In the long run you will get better performance because you can give the pack attention as needed.

So the biggest positives are:

1. You can replace runt (bad) cells easily.

2. The tubes actually weigh very little... roughly 2-3 pounds for the full pack... and unless you are so concerned about weight that it matters, then weight is not a significant issue. You would save much more weight if you switched to LiFePO4 rather than using NiCads or NiMh, so your up front decision making needs to be looked at if you have problems with weight. Choosing NiCad's or NiMh is a statement that weight is not a big issue in the first place. Since LiFePO4 cells need all kinds of fancy cell attention you can't use solderless tubes for them anyway.

3. The pack is effectively indestructable and can withstand any jolt that you can throw at it. I'd guess that the strength of the tubes themselves could withstand a sudden impact of 50g's or more. Soldered connections routinely break, but solderless tubes are incapable of breaking.

 

[TPA]

I'd guess that the strength of the tubes themselves could withstand a sudden impact of 50g's or more. Soldered connections routinely break, but solderless tubes are incapable of breaking.

I challenge the validity of this statement. Most especially the 50g, and incapable of breaking parts.

 

[HAL9000v2.0]

Someone is making some money off that thing.

I'll say 60% for series of 10 pcs.

 

[safe]

I challenge the validity of this statement. Most especially the 50g, and incapable of breaking parts.

I looked up the spec for the schedule 40 PVC pipe and they list 480 PSI as the maximum wall pressure. Doing the math on the weight of the cell (per cross section) one would be able to figure out based on this PSI number an approximation of the number of G forces it could handle before the PVC broke. I'd have to guess that it would be many G's because the cells aren't very heavy and the tubes are darn near indestructible.

If you got into an accident which was able through G forces alone to break the Solderless Tubes you would probably die as a result of such impact. (in other words the tubes might break open if you got hit by a car, but they will not break under any load caused by bouncing over bumps)

Effectively the Solderless Tubes are "indestructible". (there's nothing that can break)

Soldered connections, however, tend to break all the time because they are fragile. So the choice is really between something that can break and something that really cannot.

I challenge anyone to imagine a way that Solderless Tubes can break... go ahead... just try... I dare you... :lol:

 

[safe]

Scary Looking Accident Skidmarks

I did my usual 20 mile ride this morning before the heat picked up and while I was out there this guy on a "real" motorcycle was behind me and then passed me with some speed. Less than a mile ahead was this scary sharply steep downhill that "could" be used for a speed run except that it's just so darn dangerous because it's both blind and twisting. Add to that the fact that they are building a house now in a spot where you need traction to slow down, but because of the construction work there is dirt and gravel on the road.

Anyway...

Someone overshot the turn.... you could see a long skidmark and the place where the bike hit the guardrail. (mangling it) My first thought was that it was the guy that just passed me and so I was looking around to see a bike and rider, but I didn't see anything.

I hope the guy isn't still there dying in a ditch someplace out of view... :| (you always hear about that sort of thing) My guess is that the accident must have happened at some other time. I ride this pretty regularly so the skid marks were fresh. (within a day anyway)

 

[TPA]

First test:

Drop the tubes, fully loaded with the cells, from 2 meters onto concrete.

 

[recumpence]

Scary Looking Accident Skidmarks

I did my usual 20 mile ride this morning before the heat picked up and while I was out there this guy on a "real" motorcycle was behind me and then passed me with some speed. Less than a mile ahead was this scary sharply steep downhill that "could" be used for a speed run except that it's just so darn dangerous because it's both blind and twisting. Add to that the fact that they are building a house now in a spot where you need traction to slow down, but because of the construction work there is dirt and gravel on the road.

Anyway...

Someone overshot the turn.... you could see a long skidmark and the place where the bike hit the guardrail. (mangling it) My first thought was that it was the guy that just passed me and so I was looking around to see a bike and rider, but I didn't see anything.

I hope the guy isn't still there dying in a ditch someplace out of view... :| (you always hear about that sort of thing) My guess is that the accident must have happened at some other time. I ride this pretty regularly so the skid marks were fresh. (within a day anyway)

Wow, that's heavy duty.

My prayers are with him.

Matt

 

[safe]

First test:
Drop the tubes, fully loaded with the cells, from 2 meters onto concrete.

That's doable... I'm assuming that the tubes would be given at least enough of a wrapping so that I don't get ugly edges out of it, but otherwise that's a test that could be done. I would think that the tubes should be able to handle that without breaking and if they do I'm only out the few dollars for the PVC.

It's 98 degrees outside right now, but one day I just might try this test just to shut people up. ( imagine a two meter drop test with a soldered pack)

 

[recumpence]

How about a 30 meter nose dive with an RC heli running a soldered pack?

Yup, wrecked the pack. Heck, it even put a good gash in the paving brick it impacted!

Matt

 

[safe]

When I hit a bump at 50 mph the jolt can be rather severe (my back can get rather sore on some of the more brutal rides) and the idea of having a soldered pack that has to rigidly deal with that kind of shock seems an unreliable choice to make. With the Solderless Tubes the cells might bounce around a little in a worst case scenario, but with the spring tension they will always snug themselves right back up again. There's very little side-to-side room for the cells since they are a tight fit in the tubes. Front to back is covered by the spring. I like things that are designed to anticipate problems as much as possible... the Solderless Tubes are rugged and would work well for an off road application. I could see someone doing a backflip with Solderless Tubes and if they have a hard landing I don't see them breaking.

 

[johnrobholmes]

Seems that there would be problems with intermittent connection when it was rreally bumpy. Find out the spring rate and you could do some math to see how much of a bump would compress it.

 

[safe]

Seems that there would be problems with intermittent connection when it was really bumpy. Find out the spring rate and you could do some math to see how much of a bump would compress it.

These springs are pretty firm... I suppose that it's possible to have occasional "blips" if they were mounted vertically, but horizontally? No, probably not going to happen and these bikes don't accellerate or decellerate fast enough to cause it in the horizontal direction.

They do not in practice exhibit "blips", so experience says it does not happen. (and I bounce over all kinds of stuff at high speed)

 

[safe]

5' 11" Drop Test

I used some simple tape on the ends to protect them and keep the cells inside without providing much cushioning effect. Then in order to produce some randomness I rolled it off the top of my head and I'm 5' 11" tall. I repeated the test five times. I then took the cells out and found that some of the cells did show some signs of mild denting as they must have bounced against each other on one of the drops that landed more on the end.


So the test results show that the cells will begin to bend or break before the tubes will themselves break. The damage to the cells is trivial though and with springs they would auto-correct for the increased space. (I returned the cells to their original tubes and tested them and they still work fine... these ends caps were spares, so I felt it was okay to risk it with them)

This REINFORCES why the simple screw idea fails... the cells are easily dented and if you didn't have the auto-correction of springs they would get loose.

Soldered packs would not likely withstand a drop of nearly six feet... these Solderless Tubes passed without any problems.

The Solderless Tubes passed the "Drop Test".

(this is definitely one of the more rugged pack designs)

 

[safe]

I just passed 4,600 miles today...

 

[safe]

Overly Sensitive Charger

I have four Tenergy 24 volt chargers and one of them is simply too quick to terminate the charge. For a while I was thinking that it was some sort of "memory effect", but that was not the problem. So I'm having to restart the incorrect charger in order to get it to work alongside the rest. In order to get a true finish I have to switch the incorrect charger out for one of the proper ones at the end. (a hassle to have to work with)

It has a 1.0/1.5 amp switch to it, I suppose that maybe if I try 1.0 amp it might at least not terminate so quickly. :|

Any "tweaks" to get a charger that is overly sensitive to not cut out so early?

 

[TPA]

It's 98 degrees outside right now, but one day I just might try this test just to shut people up. ( imagine a two meter drop test with a soldered pack)

I've watched a few folks here (one in particular) giving Safe a hard time about his ideas, and I've admired his patience under some pretty extreme criticism.
Imagine my shock at being the one to unleash the inner Safe Beast

I'm glad to see that the tubes are successful, and that they are working for you. Good show old boy!

 

[safe]

Safe Forced Into A Ditch


On a road that is just barely wide enough for two cars this big industrial truck carrying some sort of farm chemical (unknown) decides to take up the whole road. I'm riding in the opposite direction and see that he's centering himself in the middle and I just figured that he would give me some room. No such luck and it even seemed like he veered TOWARDS my side as we got closer... I moved to the edge and unfortunately for me this narrow road had no shoulder and I went down into about an eight to ten foot ditch. But I couldn't know that in advance... the weeds were grown all the way up and they were standing about five feet above the street.

So I was forced into a ditch...

Damage Assessment:

Rear Rim - Bent (unrepairable because some of the spoke holes were pulled open) Fortunately I have two cheapo spare rims to choose from to replace it.

Front Rim - Slightly bent, I should be able to true it back to normal.

Left Handlebar - Bent.

Left Pinky Finger - Squashed... like being hit with a hammer... but nothing serious... in a few days it will recover.

The full leathers and helmet were great, I don't even have a scratch. My guess is that I went into the ditch at about 30 mph, the weeds helped to slow the fall, but my left hand and left handlebar hit something (probably the left side of the ditch) and so that's how my pinky got hurt. It's going to be a few days before my finger heals up and I can get all the parts on the bike repaired.

The Solderless Tubes are fine... so I guess that's "real world" crash testing. :lol:

(this was the first time the bike has been down after 4,600 miles)

A followup on the chargers...

What seems to be happening is that when you start the charge you can get this "burp" that the charger can misinterpret as a delta V signal. Once things settle down a little everything turns out okay. So what I'm going to do is when I see the finished signal from the charger I'm going to reach down and feel the tubes. If the tubes feel completely cold then I assume that it was just a "burp" and restart the charger. If the tubes are warm then I know that it really finished correctly. As long as you are nearby watching the charge this should be fine. (which I normally do)

 

[vanilla ice]

Glad you're ok dude.

 

[safe]

Glad you're ok dude.

It's better to "accept" the ditch than to try to play "chicken" with a large truck. The truck always wins. :wink:

The guy was probably laughing after seeing me go down... Missouri is "redneck country" after all. :lol:

But to be fair... we've had a really hot spell recently and if the guy was driving a truck without air conditioning for his job he might have been so out of it that he never even saw me. I had a truck hit me in my car a few years back and when I called up his phone number to figure out payment his girlfriend said:

"Oh, you're asking about an accident today... I thought you were talking about last weeks accident."

...so the guy had at least two crashes in a week. Throw in all the other problems people are facing these days and I might be the one who should feel sorry for him. On that other one I just skipped it... the damage wasn't that bad and I took care of it myself.

I'd rather forgive him... life is like that...

 

[Johnbear]

Not the kind of crash testing a person wants to do on purpose! , Good to hear your ok!

 

[John in CR]

My guess would be the self balancing act of the universe as the cause. Monday, very possibly someone goes over the rail shortly ahead of you, but you didn't stop and look around (did you at least phone it in?). Then the next day you get forced into a ditch. Glad to hear you're fine and bike damage isn't too severe.

I'm currently testing a different take on solderless tubes. I haven't found just the right tubing for my D cell nicads, so I made two 6v strings using duct tape only. I charge in series with a 12v charger and run them in parallel as a 6v9ah booster pack. It's working great after a week, including some bumpy rides on roads that are more like a rocky dry river bottom than they are like roads. My concern is more of the end-to-end force denting the bottom of the next cell, than losing connection another way.

John