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Richard230 replied to the thread 1979 XS750 electric conversion.
" I can understand why the engine is missing from that XS750 chassis. As I recall, the 750's engines were not one of its strong points from a reliability standpoint. "

1 Hour Ago

Richard230 clicked Likes for this post: 1979 XS750 electric conversion by biothundernxt

1 Hour Ago

Spoonman replied to the thread 1979 XS750 electric conversion.
" Looks like a nice easy fitout dude - great job so far - and well done on the parts selection.
That motor marries pretty much perfectly with those modules and that controller in terms of what they can each draw and source respectively.

WRT the strain gauge notion - have you worked with them before? They can be a real PITA at the best of times.
I'd be more inclined to put a pressure sensor onto the brake line. There's no shortage of vendors out there doing custom lines - all you need is a split line terminated with the appropriate fitting.
Far more reliable measurement.

The other route you could go would be similar to the Vectrix approach - they use a throttle which goes both directions. Roll back for acceleration, forward to deceleration. Added bonus is that the latter allows it to reverse as well.

Whatever way you go, I'd stay well clear of strain gauges unless you're well accustomed to working with them (I have quite a few hard yards with the things in custom applications) - they'll only break your heart.

I don't see any mention of a BMS in there - they aren't a must, but if you're not using them then you'll want to leave yourself with the ability to easily check and balance manually.
Doesn't have to be anything fancy, but you will want to have something. Those leaf modules are unbelievable good at staying in balance, but you'll still get variations. "

4 Hours Ago

biothundernxt created the thread 1979 XS750 electric conversion.
" Alright, lets get this thread started.
I recently acquired the aforementioned XS750
I will add pictures later this week.

I have ordered the following parts:
17" by 6" 12kw rear hub motor from qsmotor (configured for 145kph)
300a ANT bms with screen.
Kelly KLS96601-8080I
A 220v charger for 96v lipo at 20A
Swingarm from a fazer since my bike stock was shaft drive.

I already have lying around:
A pile of matched nissan leaf batteries to make my battery
The bike itself

Things I still need to get:
Brakes for the rear wheel (I'm in contact with some suppliers right now)
J1772 adapter to feed the charger
throttle (considering either a domino pot throttle if i can find one, or a cable throttle pot module)
Dcdc converter (suggestions welcome)
Main power contactor

I did some looking about but I could not find any mention of anyone using this motor.

I plan to document my entire build process thoroughly with lots of pictures and data.
There is a local place that is willing to let me use their dyno too when I get it put together.

For variable regen, I plan to use some kind of strain gauge on the rear foot brake. I havent figured out the details yet, but I am sure emulating the potentiometer input to the controller for that with a microcontroller based on the output of the strain gauge should not be too hard.

I don't expect this to be a drag strip monster, but having some actual data out there should be informative.

Any other suggestions are welcome too.

Here are some photos of what I have so far:
This is how it looked the day I bought it:
Attachment 8466

Then I started stripping things down:
Attachment 8467

Here I tried fitting one of my leaf cells for reference to see if they would fit, and what orientation might be best:
Attachment 8468
Attachment 8469

More recently, I assembled the pack itself.
At 96v nominal, I estimate that the pack should be around 4.3Kwh. I plan to build another pack at some point later with LG chem cells that would be around 11kwh, but those cells are expensive and I already have these, so...
Attachment 8470

Here is a cardboard box made to the dimensions of the aforementioned battery module for scale reference.
I need to build an enclosing box to hold this and some of the other electronics in.
Attachment 8465
Attachment 8471

And lastly, here is a picture of that fazer swingarm I ordered:
Attachment 8472

I hope it fits. Some other conversions from shaft to chain for the XS750 used this swingarm, so fingers crossed that it will not require much modification.
We'll see. It should get here pretty quick, it is only going across town. "

7 Hours Ago

biothundernxt replied to the thread Chinese E-Vader/E-Grom/E-Monkey.
" Well that's disappointing...
The company I ordered from canceled my order because they miscounted inventory and cant get any more in stock because of covid...

Oh well...
Back to plan A then.
Plan A was my other motorcycle project: Yamaha XS750 conversion.
Ill post another thread for it.

Sent from my GM1915 using Tapatalk "

8 Hours Ago

gregjet replied to the thread Aprilia RS125 2-STROKE conversion.
" Definitely can be resuspended. You need a friendly experimental and knowlegeable suspension person hands on.
The big problem with suspending it properly is the crazy unusual weight distributions
. You have a crazy light chassis and swingarm, mated to a crazy heavy wheel, with massive torque across the rev range. It is completely out of the realms of the experience of almost everybody. I am NOT saying it can't be done, just that it is going to take a VERY intelligent and clean slate approach. Pretty much every chassis and suspension parameter will be wrong for optimium handling.
Good luck. It is the sort of problem I would love to be involved in solving and ,I bet, so would any creative suspension person .
My approach would be a mid engine but I would love to see an elegant solution to the rear hub motor problem. "

12 Hours Ago

Stevo replied to the thread Aprilia RS125 2-STROKE conversion.
" Can the rear shock be resprung and dampened? I checked my suspension go to RaceTech and they only have kits for RS250 "

18 Hours Ago

gregjet replied to the thread Aprilia RS125 2-STROKE conversion.
" Take one of the best handling motorcycles on Earth and add 43kg to the back wheel of a bike that weighs not much over 100kg total. Unsprung to sprung mass is not exactly ideal. Rear suspension will be completely overwhelmed. "

1 Day Ago

MrModify replied to the thread Aprilia RS125 2-STROKE conversion.
" It's a QS Motor 14kW (nominal) and 34kW (maximum) hub-mounted motor. 43kg. 350Nm of torque. "

1 Day Ago

Nifty replied to the thread Hi from Tasmania BMW K100 Electric..
" Hi Guys. Stevo! You said good luck with the programming,??? Havnt done so well yet. After two years plus tinkering the motor actually turns !!!. Have to dig deeper into the secret files of Curtis to extract the righ dial ups i need. Jon at Bylong/Catavolt is being very helpful,pity my brain isn’t. However ill peas on and hope to have some more positive updates and pic soon. Cheers guys, and don’t let this Covid scamdemic get u down. "

2 Days Ago

Spaceweasel clicked Likes for this post: Hi from Tasmania BMW K100 Electric. by Nifty

2 Days Ago

EVcycle replied to the thread Battery Help!.
" Chevy Volt batteries come in a 48 volt single pack. Ready to roll for around $500.
I have used them in several projects. You can purchase 50.4V Lithium chargers for about $250.
Use the Controller as a BMS and have fun!

Ed "

4 Days Ago

Stevo clicked Likes for this post: Hi from Tasmania BMW K100 Electric. by Nifty

5 Days Ago

Stevo replied to the thread Battery Help!.
Quote Originally Posted by 4r3st3r View Post
Hi all,
Some questions:
The BMS is attached to the battery (?) so would a battery that I buy come with a BMS pre installed. Do I need to program or edit the BMS to ensure that it keeps the cells in the battery balanced and with enough voltage? Or can I leave it to it, and use / charge the battery as I would with a lead-acid battery?
Is it better to get a battery custom built with the correct voltage / amperage output with a BMS that can handle that?
I think I have two mounting places for batteries, is it better to buy two 48v batteries (each with a BMS) and mount them in parallel, or two 24V batteries and mount them in series (with a BMS each, or one for both?)
If you buy from a salvage yard to get a good deal on Nissan Leaf modules or Chevy Bolt modules you will need to learn how to cut them apart.
Same with a Tesla pack, but all of those flashlight batteries will be a challenge to incorporate a BMS. The pouch cell modules are easier to deal with.
If you are building your own pack, like I did, you can arrange them anyway you want or need to. since this is your first build, try to go with one stack in series and figure out how to mount them on your frame space. They can be divided into groups. I have 3 groups of battery pouches all wired in series. There are a few BMS options available,,,, you'll have to do some research. I went with the Thunderstruck BMS.
ElectricCowboy has some good advice for you, But if you want to do your own from scratch, AND if you have the ability to weld and fabricate your own mounts and stuff, you can build your own for 1/2 the cost of a Boom Moto "

5 Days Ago

Nifty replied to the thread Hi from Tasmania BMW K100 Electric..
" Hi Spaceweasle. Made a new clutch center bolted to the clutch basket of plates etc. Keyway on motor shaft to fit center,same offsets all round just a different input,ie, electric motor. Made in conjunction with the adapter plate so all bolts up neat.Time will tell how the box /motor combo works.Bronze bush in end of motor shaft to center the box input shaft.Am trying to upload more as i can,stay tuned. "

6 Days Ago

Richard230 clicked Likes for this post: Boom Moto actually delivering bikes by Electric Cowboy

6 Days Ago

Electric Cowboy created the thread Boom Moto actually delivering bikes.
" Boom Moto uploaded a video about actual deliveries, this is super impressive. I personally saw a custom Orange bike with some Native American designs get picked up by a customer while Morgan and I were there. These guys are really working hard.

https://www.youtube.com/watch?v=pdOagsh_9SI "

6 Days Ago

Spaceweasel replied to the thread Hi from Tasmania BMW K100 Electric..
" How did you interface the motor with the transmission/clutch? "

1 Week Ago

Electric Cowboy replied to the thread Battery Help!.
" A lot of these answers depend on your build. You might want to consider one of the Boom Motos. They are not as polished as Zeros or Energicas, but they are 10kW hub motors with 6-9kwh batteries. and they cost $6500 to $7500 they are reasonable quality for the cost, and EASILY hackable. Way better to start with one of these and modify than to build from scratch if you are new. It will also help you learn a lot.

They aren't perfect, but they are good enough for their price. "

1 Week Ago