Safe's Electric Bike Project #001

[safe]

Newly Paved Roads!!!

I'm a lucky guy. One of my "cruising" rides that goes through a nice little valley has been repaved. It's so nice to get smooth fresh asphalt.

I found a new loop to ride and it takes me down a hill I normally climb up. It's the steepest road around.

On this downhill I reached:

52 mph!

 

[Beagle123]

The soldering gun also seems to sometimes get hot and sometimes not, like it's peak temperature is not very constant. (so sometimes it works fine and others are a struggle)

Safe, you see those little screws that hold the tip into your soldering gun? loosen them a little, then make sure the tip is all the way in, then tighten them hard. Trust me, you'll be happy.

 

[safe]

Safe, you see those little screws that hold the tip into your soldering gun? loosen them a little, then make sure the tip is all the way in, then tighten them hard. Trust me, you'll be happy.

I do that already. Also, I clean the tip really well and that increases the ability of the soldering gun to heat. The real problem is that it's one of those very low powered pen style soldering guns. I've owned a "real" full powered soldering gun before and the difference is dramatic. With the powerful guns you can pull the "trigger" and the tip gets hot in a matter of seconds. With the pen style you have to plug it in and then wait for about 5 minutes for it to get really hot. The moment you start to solder the overall pen gun starts to cool. So what happens is if you don't wait long enough between soldering tasks the gun doesn't hold it's full strength. I just need to buy a better soldering gun and that will make things easier...

 

[roguesoul]

Safe.
I want to build a trike, with the connection between the back front and wheels just like your 001 frame.
So, with say.. 90 lbs for batteries and my 180 lbs. would 3/4" tube with a wall thickness of .049" have enough strength?
Oh I'll use 1020 DOM tubing.

Thanks.

 

[safe]

I want to build a trike, with the connection between the back front and wheels just like your 001 frame.
So, with say.. 90 lbs for batteries and my 180 lbs. would 3/4" tube with a wall thickness of .049" have enough strength?
Oh I'll use 1020 DOM tubing.

If you do like I did and created the "Ducati Style" space frame with small diameter tubing and very well thought out bracing it should be light and strong. Just be sure that you think REALLY HARD about where your tubes go. I can imagine someone using the small tubes and then making a mental mistake and simply not adding a critical tubing element and then things end up failing because of a mistake. Think of all the possible ways that loads will effect your trike and distribute the load as evenly as you can. The space frame is all about dispersing energy into the "web" of tubing.

 

[safe]

I'm at 2,748 miles... just two short of 2,750 miles.

If I can end the year at 3,000 miles that would be pretty good...

At this point the bike can officially be labeled a "success" after all those troubles with the transaxle have been cleared up. If the final mileage goes to 5,000 in the end that would be really incredible for this bike.

That's a lot of riding for $138.

 

[safe]

Now 2,905 miles. (150 miles in 7 days)

I'm hoping to get to 3,000 miles in the next week...

(this extra long summer weather is giving me a lot of extra riding time)

 

[safe]

The 3000 mile distance has been achieved!

And just in time because the winter air has arrived....

 

[Doctorbass]

!!

At 50Wh/km you used around 150 000Wh!!

Doc

 

[safe]

Halloween Bondage Photo

Just in time for Halloween... my bike being used as a "slave" in a bondage ritual.... okay... maybe not, but it is a warming pad attempting to warm up the batteries. :lol:

I tried it and it does make a little bit of a difference, but raising the temperature any more than a few degrees above the surrounding air is going to require a fancy wrap that keeps the warmth in better. Ideally a sort of blanket that had velcro to keep it snug and warm. The pad only heats up to about 100 degrees so when it's 60 degrees outside the heat loss to the air is pretty bad. Also, once you start to ride you get hit by a wall of cold air, so having a fairing on the front would help a lot to keep the warmth inside.

 

[fechter]

Put an old jacket or vest over the whole thing to insulate it.

 

[safe]

Put an old jacket or vest over the whole thing to insulate it.

Yeah, I placed a big plastic tarp over the whole thing. It might be a good idea to blow some heat underneath the bike too. I just checked the temperature and it's currently 34 degrees outside and about 60 degrees in the garage. It will warm later today to about 60 so I'll try a ride late in the day and see.

 

[safe]

A Big Improvement

I combined the warming pad with a plastic tarp and an electric heater with fan to get some good heating results. I don't know how warm I actually got the batteries, but they felt warm to the touch before riding.

The Results:

On a particular stretch of road where I have a limited exit speed out of a corner (making it a fairly constant baseline) leading into a slightly downhill straightaway I can in the summer months hit a top speed of 40 mph. When the bike is cold I'm lucky to hit 35 mph. With the battery warming techniques I was able to hit 39 mph.

Eventually the cold air rushing past the batteries starts to cool them so you don't get more than about 15 minutes before it goes back to it's more sluggish colder performance. More insulation or a fairing would help.

MythBuster question:

Can warming SLA batteries increase cold weather performance?

The answer is a definite "Yes".

Now I just need to perfect this a little more... :?

 

[Miles]

Now I just need to perfect this a little more... :?

Plenty of liquids before setting off and then the "micturition method"?

 

[safe]

Plenty of liquids before setting off and then the "micturition method"?

I had to look that one up... so pee into a tube and circulate that around the battery?

Hmmmm... that's a little more extreme than I had in mind.

 

[Miles]

I had to look that one up... so pee into a tube and circulate that around the battery?

Hmmmm... that's a little more extreme than I had in mind.

If you approached the corner fast enough, the process would be automatic :lol:

 

[safe]

First Ride of the Year

We got a brief warmup today that will be followed by snow tomorrow. It got up to about 70 degrees and my batteries were probably internally at about 60 degrees because that's what the garage temperture was. The bike was sluggish... after going 3,260 miles and now beginning it's third year I'm pretty certain that this will be the last year for these batteries. When it gets really hot it will be good enough to get a decent ride from them, but they just can't pull many amps right now. Cold weather (compared to summer) means low peak amps. The best speed I could get up to was only 36 mph... which is well below my old peak. (and it was even on a slight downhill)

I tried out my new leathers and they are a little too tight. Hopefully they will loosen up with more use, but it's possible that I'm going to have to do more modifications to get them to be really comfortable. Right now the problem is right around the knees... it's just too tight there. Hmmmm...

 

[safe]

Second Ride

Started out 40 degrees in the garage, but it got up to 65 degrees in the afternoon. Still no power... at least not sustained power. I can get about one hard accelleration and then the available easy power is depleted and it starts to sag. Hard to know if there's anything left in these batteries now.

 

[fechter]

Lead-acid sucks.

 

[safe]

Lead-acid sucks.

Yeah, but it's pretty cheap to own. 3,260 miles for $138 is only 4 cents per mile. I suspect that the threshold for using these worn out batteries is at about 80 degrees because that's about the temperature that they cut out last summer. The garage is now up to 50 degrees and the high today will be in the 70's. I will try it again and watch the difference.

One idea I'm thinking about is to replace my 3 - 38Ah cells with 4 - 18 Ah cells. Seems that the 18 Ah cells are exactly half the size (in width) and the same dimensions otherwise, so my three "units" would drop to two. That way I'm running about one third lighter (54 lbs verses 86 lbs) and also using 48 volts. My simulation shows that my top speed goes from 40 mph up to 47.3 mph when running at 40 amps.

So this might make the bike fun in a new way... less range... but more top speed. However, the smaller cells will tend to wear out faster.

This would cost $33.92 * 4 = $135.68.

http://www.batteriesasap.com/46.html

 

[safe]

It got up to 70 degrees and so my battery didn't really get hot enough to know for sure if it will recover. After three or four rides and then recharges (for about a mile or so) each time the energy was better, so there is still hope for these this summer when it stays 90 degrees for about three months straight. I'm also coming down with a cold so my equilibrium is off and I don't feel so great. Tomorrow it returns to sub-50 degree temperatures. I will report back at the next chance for testing...

 

[D-Man]

My sla's are getting better too. The worst it got was 12 mile range from being outside in the cold. After bringing the bike in house and cycling and lots of trickle charging, it went 18 miles the other day and wasn't all the way down yet. Don't give up. I'm not.

 

[safe]

My sla's are getting better too. The worst it got was 12 mile range from being outside in the cold. After bringing the bike in house and cycling and lots of trickle charging, it went 18 miles the other day and wasn't all the way down yet. Don't give up. I'm not.

It seems to be at least one percent of power loss for each one degree of temperature drop. Since my batteries are old they can just barely pull the peak amps now (compared to having unlimited excess long ago) so in order to pull the amps I'm needing near perfect temperatures. It does seems that when you shake the batteries up a little with the desulphation and the charging that it wakes them up. If they sit all winter the internal chemistry seems to just go dormant. However... these batteries are simply getting old... I'm just hoping for one more summer with them. At the same time I'll be working on other things.

 

[Lessss]

I don't need to worry about shaking the batteries, with the amount of potholes and cracks in this city just driving provides all the shaking they need.

 

[safe]

True Problem Identified

I had been charging up the bike normally and would go for a ride and it would be fine for about a minute and then the power would drop. After returning home I would check the voltage and the "group" voltage would show that it was empty. It "appeared" like the whole pack had gone down.

Now sometimes you can lecture all day long about LiFePO4 and how:

"A pack is only as strong as it's weakest cell"

...and yet when it comes to diagnosing your own bike you somehow can manage to overlook what you just were preaching. Sometimes it's like in the show "Medium"... your intuitive mind somehow is telling you:

"Look for the weak cell."

...but your conscious mind doesn't want to listen. Anyway, I separated the cells and looked at their voltages after the ride separately and realized that two were completely full (12.5 volts) and the third cell would be down at 8.5 volts or so. What was happening is it was looking like the whole pack was going down quickly, when in reality only one cell had lost the ability to hold a charge. At the beginning the voltage looked fine, it was only at the end of ride that you could notice.

One might wonder how much longer the other two have before they "fall off the edge" and also become unable to hold a charge, but it seems worth it to buy a new cell and see if maybe I can get some more miles out of what I have.

I'm thinking I'll buy two 12 volt 18 Ah cells and then I can run them either in series or parallel. When in parallel they will give the same 36 volt overall result, but I'll set things up so that I can toggle into 48 volt mode in order to do some speed runs.

This should be a cheap way to get another summer's worth out of the bike.