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EVcycle replied to the thread Adding a centrifugal clutch to the drag bike..
"
Quote Originally Posted by Spoonman View Post
When you say AC you're referring to PMAC not squirrel cage I expect yes?
Yes, A Motenergy 1507. "

2 Hours Ago

Spoonman clicked Likes for this post: Adding a centrifugal clutch to the drag bike. by EVcycle

4 Hours Ago

Spoonman replied to the thread Adding a centrifugal clutch to the drag bike..
" When you say AC you're referring to PMAC not squirrel cage I expect yes?

You've answered my question in any case - it sounds like there's a necessary lag until sufficient angular velocity is developed to really launch the thing (which makes perfect sense of course), so having something in there which permits you to have it spun up before you try and move certainly makes sense alright. "

4 Hours Ago

EVcycle replied to the thread Adding a centrifugal clutch to the drag bike..
"
Quote Originally Posted by Spoonman View Post
How sure are you that this isn't more to do with how your controller is programmed than anything else?
If you're dealing with some sort of software limit on the ramping rate for current, then the flywheel dump may not help as much as you expect as the controller is still going to attempt to regulate the rate of change - granted if any such rate is RPM linked then it may not try quite so hard... but the point is that there are a substantial number of unknowns there.

Once the magnetic fields are established (for which I would expect there will be a larger time constant in the case of induction than PM), then the torque should be pretty much instant in any practical terms. Only reason for this not to be the case is if something is the control stages is trying to be too clever.
AC motors.....100% torque at zero RPM is still not moving HP. This is not always a bad thing as in Drag racing you do not want to "blow your tires off"

I have everything running at 100% in the controller (2 different controllers and motors) The start seems soft until I get to about 100 RPM or so.

I recently had an interesting chat with one of the leading AC motor manufacturers explaining my 100 RPM theory and was surprised to find out that the was the magic number to get things really rolling...100 RPM. The had proven it on a dyno.. (go figure)
Depending on your gearing, you may get to 100 RPM very quickly so it may not be noticed, but I have two vehicles with no transmission and am drag racing them to 100+ MPH in a 1/4 mile.

I still think a centrifugal clutch would help us with our ET.

Ed "

16 Hours Ago

EVcycle clicked Likes for this post: Adding a centrifugal clutch to the drag bike. by Frank

16 Hours Ago

EVcycle created the thread Stacking chargers (Just in case you wanted to know.).
" Yes Dorthy you can mix and match chargers if you do it right (This may have been discussed already), Here is my setup.

In the photo you will see 3 chargers Juicing up our Legend dragcar. I use a similar, but different, setup on my Drag bike (more on that later)

Attachment 8508

There are three chargers, one 100.8V 8A charger. It is a smart charger, but with no reverse protection. I know it this as I had a millisecond short and the second 100.8 V 8A one that was on the board toasted itself even with proper fusing.

The other two (stacked) ones are 50.4 4A really smart chargers I got cheap while I wait on some more 8A ones to arrive from China.

They are charging the same battery pack. (6P2S 100V 1350A) Chevy Volt packs

The two smaller chargers are in series to give me 100.8 at 4A and are connected via a 10 foot cord to the front of the battery pack.

The 8A charger is on a 15 foot cord and connected at the other end of the pack. There is enough resistance in the cords and batteries that the changers do not fight each
thinking there is a full charge until there really is one.

On the dragbike I have a 50.4V 12A and a 67.2v 12A charger (2 Chevy Volt Packs) The packs are split with a contactor in between them so that each battery has it own charger.

It all works great. Recharge times at the track are from 20 to 45 minutes depending on if we are at a 1/8 or 1/4 mile event.

Enjoy!

Ed "

19 Hours Ago

Richard230 clicked Likes for this post: The Long Way Up by ElMotoMike

2 Days Ago

Spoonman replied to the thread 1970 Honda CT90 Electric Conversion.
" To be fair, at least you'll be paying for the best solution and not a hack job.

Nice project. "

2 Days Ago

Spoonman replied to the thread 1979 XS750 electric conversion.
" Yeesh - that's a good sized gap there alright.
Are those studs integrated?

I don't see that arm squeezing down enough to make the studs work. If you could change them out then you could use heavy spacers to take up the gap - it wouldn't be pretty bit I expect it would serve well enough and I expect you'll need to do something to that effect in any case to maintain cable clearance.

To do it right though you're looking a refabrication IMO. Retain the pivot and have some new box section with the right dimensions welded up with some appropriate relief for the cables. "

2 Days Ago

Spoonman replied to the thread Adding a centrifugal clutch to the drag bike..
"
Quote Originally Posted by EVcycle View Post
the Toque at Zero RPM is not really translating to the wheels when the motor is stationary in a AC system.
How sure are you that this isn't more to do with how your controller is programmed than anything else?
If you're dealing with some sort of software limit on the ramping rate for current, then the flywheel dump may not help as much as you expect as the controller is still going to attempt to regulate the rate of change - granted if any such rate is RPM linked then it may not try quite so hard... but the point is that there are a substantial number of unknowns there.

Once the magnetic fields are established (for which I would expect there will be a larger time constant in the case of induction than PM), then the torque should be pretty much instant in any practical terms. Only reason for this not to be the case is if something is the control stages is trying to be too clever. "

2 Days Ago

ElMotoMike replied to the thread The Long Way Up.
" Started watching today. Those generators are coming in handy. "

2 Days Ago

Frank replied to the thread Adding a centrifugal clutch to the drag bike..
" Before upgrading to a larger controller on my drag bike a few years ago, one of the options I looked at was using a snowmobile clutch. You could keep a motor close to Max power with some sort of cvt.

Sent from my SM-T380 using Tapatalk "

3 Days Ago

biothundernxt replied to the thread 1979 XS750 electric conversion.
" I sized up the motor with the swingarm I got off the Fazer, but it looks like I will have to do some modifications... Any suggestions?Attachment 8503
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Attachment 8507
Attachment 8505
Attachment 8506 "

3 Days Ago

biothundernxt replied to the thread 1979 XS750 electric conversion.
" This week, I built a temporary stand for the motor out of wood, and hooked up the controller and a small 48v battery I built for another project to test everything:
https://youtu.be/zs7Qzl2n8bo "

3 Days Ago

Richard230 clicked Likes for this post: 1970 Honda CT90 Electric Conversion by MegaWatt

3 Days Ago

MegaWatt created the thread 1970 Honda CT90 Electric Conversion.
" I have a 1970 Honda CT 90 Trail that I've owned since it was new. About the only time I ride it now is to the mail box in summer. Recently my son, who is a motorcycle mechanic, had to rebuild the carb due to a leaking float. It runs like new again.

Being a retired electrical engineer, I've been thinking about converting it to electric for several years. Recently I decided to go ahead with the project and have already made a couple of mistakes. I want to keep the bike looking as original as possible. My first thought was to use a mid mount motor and keep the original rear wheel and chain drive. Due to problems with the chain drive and lack of space for batteries, I decided to go with a hub motor and use the engine space for batteries.

I bought another swing arm from eBay to modify for the extra width of the hub motor. I want to keep the chrome rear wheel so it matches the front. I decided on the QS250 3000W 50H V3 Spoke Hub Motor with drum brake. I contacted Buchanan Spoke & Wheel in CA. and they indicated that the hub motor could be laced into the 17" wheel. After receiving their reply, I ordered the hub motor and a new chrome rim and had them shipped to Buchanan. Immediately after buying the motor and wheel I received another message from Buchanan, "Just a warning, that chrome rim going to one of those large motor hubs is not the best idea. Those motor hubs are generally 8-10 inches in diameter which is much wider than a CT90 at just over 5”. You’ll be running into quite a bit of bowing, even if we only run that wheel cross 1. An aluminum rim would be a much better bet. If you buy one pre-punched elsewhere at least there is a chance that we might reangle it to mitigate some of the spoke bowing issues, and if you buy one from us we can angle it for that large hub. A chrome rim is, pun intended, set in steel and there isn’t any adjustment to be made. We can certainly do it, but we definitely do not recommend that." GREAT, after I've already spent $750!

I sent them a reply asking if they had a 17" alum. wheel in 1.4" to 1.6" wide. I just replaced both tires on the bike and any wider wheel would cause problems with the rear fender. Presently waiting on a reply and doing a lot of thinking! "

3 Days Ago

Richard230 created the thread Anyone want to buy an electric scooter company?.
" And it looks like another one is about to bite the dust. (Just check out the manufacturer brand names of the sub-forums on this site. A lot of elmoto manufacturers have bit the dust over the past decade): https://electricmotorcycles.news/cez...ness-for-sale/ "

3 Days Ago

Spoonman clicked Likes for this post: 1979 XS750 electric conversion by biothundernxt

1 Week Ago

Richard230 clicked Likes for this post: Will It Wheelie, Zero SR/F by Electric Cowboy

1 Week Ago

jhaggerty created the thread Zero 75-5 Motor.
" I have a Zero 75-5 motor for sale in the Bay Area California. I've shifted to riding production bikes (2021 Energica SS9+ ) and am hoping to find someone who will make a cool project out of this. I am willing to ship, but it will likely be decently expensive since the motor weighs about 40 pounds.

Price: $750


I am also parting out the motorcycle I built that has a Kelly KDHE 600A controller, ME1003 motor, and 11.5KWH of Gen 4 leaf batteries with a BMS that consistently got me about 60 miles of range.

looking for $2500 for the batteries (local or drive to me to pickup only)
$800 for the motor and controller pair
or $3000 for the whole bike with title "

1 Week Ago