Xtreme XB-600 (electric scooter mods)

[captainslug]

Since I won't be using the custom e-crazyman controller for the motorcycle project I looked into using it to upgrade this to 72V. I will need to test the controller with this motor to see if it can get the right phase for it, and if that is successful then it's only a matter of adding $40 worth of parts.

It will involve replacing the dc-dc converter with a 12v 5ah battery (which I already have), adding onboard chargers for the 72v and 12v packs, and adding relays for the ignition and brake light circuits.

I've also ordered a set of replacement tires since the stock ones are really flimsy and treadless.

[captainslug]

New tires! 90/90-12 (i.e. 12-3.00) from Bikebandit.com arrived. $47 shipped for the two together. They're a slightly tight fit on the rim and take a short while to seat once the tubes are inflated. But it probably would have gone smoother if I had bother to wet the bead of the tire before trying to get them on.

The difference in handling is easily felt. While my speed on level ground is unchanged after recalibrating the bike computer, I now slow down a bit less on hills and the traction improvement is great. No skidding under hard braking, and no sliding on fine gravel.

[captainslug]

I followed the advice of this excellent guide to series/parallel switching.
http://visforvoltage.org/forum/3166-...t-2-simplified
And installed a bank of 12 volts chargers under the seat.

To drive, I plug in the series connector that connects the 60v pack to the controller.
To charge, I plug in the parallel connector that connects each 12v battery to its individual charger.
I will no longer have any issues with one bad cell in my pack destroying the rest of them. And if I upgrade to a higher voltage later, it won't involve as much rewiring.

[vinny1989]

So its better to charge each battery independently? Doesn't the weight gain of the separate chargers affect anything?

May i ask a few questions?
What are the physical size of your batteries? and, weight, if you'd be so kind?
If you dont mind, what is the overall weight of the scooter? Im guessing lighter than a petrol/gas one...

Thanks

[captainslug]

Originally Posted by vinny1989

1. So its better to charge each battery independently?
2. Doesn't the weight gain of the separate chargers affect anything?
3. What are the physical size of your batteries?
4. and, weight, if you'd be so kind?
5. If you dont mind, what is the overall weight of the scooter? Im guessing lighter than a petrol/gas one...

1. Yes, it's better for the longevity of each individual battery. Especially if the pack involves more than four. It also allows me to monitor the health of the batteries individually, so that I can replace them individually as needed.
2. Nope. It's not like they weigh very much.
3. 7 x 6.5 x 3 inches
4. 13.5lb each
5. 200lb

[vinny1989]

Ah, makes sense.

Its surprising how light those batteries and your whole scooter is; 200lb = 91kg. An average 50cc scooter is over 100kg..

Thanks for the information captainslug. Your scooter has inspired me.

[captainslug]

Now that I travel much further on a more regular basis I have been crunching some numbers to figure out the actual cost of operating this scooter over thousands of miles.
Unfortunately batteries are not as cheap as they were when I first bought this scooter, and having to buy them 5 at a time is not proving all that economical.

A full set of non-deep-cycle batteries ($211 per set) will last me at best 2,000 miles.
Comparatively a gas scooter is significantly cheaper no matter if it gets 60mpg or 115mpg.
A gas scooter averaging 100mpg running on premium (@ $2.90/g) would only cost $58 every 2,000 miles. Add however much is needed for regular maintenance for that distance (oil changes and replacement tires) and it will still be likely to cost half as much as an electric scooter. All while performing slightly better.

[MazdaMatt]

It may be a lot of number crunching and speculation, but I'd love to see what you figure the costs are with a "premium" battery. You'd have less weight, higher efficiency and longer lifetime.

[captainslug]

Originally Posted by MazdaMatt

It may be a lot of number crunching and speculation, but I'd love to see what you figure the costs are with a "premium" battery. You'd have less weight, higher efficiency and longer lifetime.

I'm not sure I can accurately predict that, so the only way to find out would be to buy said batteries and run them until they die.
I'm not keen on buying any more batteries for the scooter since I've run into a wall in terms of upgrading it any further.

I just bought this Tomos Streetmate to replace it.

Less than a third of the cost per mile, quadruple the range (100mpg), and 15 extra mph (tops out at 40mph).

[Frank Lee]

Hmmm... you went from electric to gas...

I went from gas to electric.

Difference is, I got a Songi electric bicycle and I've hardly lifted a finger to mod or work on it. 60v 5-battery pack, hub motor, LED lighting, and I can pedal it a bit at low speeds to help out if I want, all came that way from the factory. Charges with 220v. Only funky things I've done are make an adapter cord from an old dryer cord and an outlet box as the 220v charger has a 110 style plug; and I put a spacer with longer fasteners on the front basket to get the lid further away from the headlight.

I don't have performance stats- no time/distance/speed instrumention. I'm going to add a bicycle computer too but it requires custom mounts.

I've actually been thinking of a unit with lower capabilities! What kind of a nut would want that? Rationale is, since I'm not even going to dream of going on the highway to the next town with this thing, it is strictly an in-town run-about. I've been using it in that capacity for a couple months now and have discovered a few things; one is it has 4 electric "speed ranges" in addition to the infinitely variable twist-grip controller, and usually 1st and 2nd are quite fast enough. Sometimes I venture into 3rd and almost never into 4th as I figure that's needless draw on the batteries. So I needn't dream of mods for higher speed (saving that for EV cycle or car). The other thing is I've yet to draw the pack down more than 50% (according to the 4-LED display) after my usual running around, and recharge usually takes from 1 to 4 hours.

I'm thinking a unit with less speed and range would be even more suitable and as you mentioned, batteries are not cheap anymore so a smaller replacment pack would be a good thing re: cost and weight. I have an aluminum frame full-suspension mountain bike that I think would make an ideal EV candidate. Not only would I go from hardtail to full-suspension, but the whole thing would be significantly lighter and the pedalling ergos and pedalling gears would allow me to help out much more, which I am willing and eager to do (the Songi actually discourages pedalling (i.e. helping out on rises at cruise speed) as it is fixed gear and quite low at that). Some 26" high pressure slicks would help out with the rolling resistance too- I fitted my heavy old steel full-suspension mtn bike with some earlier this summer and wow- can pull top gear now for some distance where with the knobbies I couldn't, even at the same 65 psi.