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Squat - TPD's experience/development bike

74K views 239 replies 14 participants last post by  toddshotrods 
#1 · (Edited)
I've actually had this bike for a while, and to date it hasn't cost me one penny. :) The bike is a Honda CM400, that I bartered a few hours of fabrication work for, and promptly "bobbed" (cut off the entire rear section, lowered the rear, and welded struts in). :D The engine had passed on, and was already gone, along with all the body parts. It will exist, for the most part, on Scrape hand-me-downs and business R&D projects; meaning mostly free. As I develop my line of EV bike parts, I will test some on Squat. It will also be a client/customer "experience" bike, that will allow people to intimately experience EVs, many probably for the first time. Squat is not intended to be a practical motorcycle; it's really a glorified scooter. My initial plans are for 25-30mph and 20 miles of range, like a plug-in scooter might have. The reason I am finally posting it here is it is about to finally become a functional bike.


When Scrape gets its new motor, the little ProTech motor will go to Squat (small cylinder under the seat). Originally, just as it was on Scrape, I will just have a 12-volt battery hooked up to it. When I upgrade to a better controller and batteries in Scrape, that setup will be installed in Squat. The battery box (large cylinder) is going to be fabricated from sheet metal, with smoked Lexan sides. It is 12" in diameter X 8" wide, and will hold eight of the little UB1250 AGM batteries - same amount that fit in Scrape's current box - get it?;), or up to 32 of the large Headways (the 20 mile range figure). The only things I will have to actually purchase, in the immediate future, are the supplies for the battery box. It is a structural component in the chassis, and will be permanently welded in. The front down tube will curve back into the box. The controller and electronics will float on Lexan over it.
 
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#2 · (Edited)
I was playing with the numbers for Squat, just for the fun of it, and found some nice "freebies". By running the batteries all in series, and over-volting the motor, to create a 96 volt system, it would have around 70 mph top speed, and 25-50 miles of range (hypermiling for the higher number). That would be possible in the same plan, if Scrape is able to pass down an Open Revolt controller, someday.

The eight AGMs in series would be 96 volts, but only 60 amps max draw, so the controller would have to make up for what the batteries couldn't supply. With the Headways, it would be 102.4v, and 150 amps max - more than enough.

Adding to all this, I just purchased a 58T rear sprocket that, combined with the extremely light overall weight, will substantially reduce the current needed for accelerating from a standstill. In Scrape, I pull 110-120 amps for a few seconds, then it quickly trails down to 30-40 amps. The motor is rated for 31 amps. I wasn't going to buy anything, other than the battery box supplies, but the bike has a 30-something tooth rear sprocket now and I didn't want to risk hurting the motor. Scrape's final drive ratio is 3.75:1, and Squat's will be 5.8:1 now. Combined with less weight, it should be really easy on that little motor. I am still going to have to pull it apart someday and bore cooling holes in the end caps, and fabricate a forced air cooling system.
 
#3 ·
While I wait for parts to start streaming in for Scrape (beginning tomorrow), and to get myself in a CAD state of mind for some more mundane client projects I have to do this week, I designed Squat's seat. It's designed to appear much more involved and elaborate than it really is. A lot of stuff I've used before, arranged a little differently. Of course, my Bat-T logo, the crosshair rivet points from Scrape, tweaked and vectorized Photoshop lightning bolt, etc. The "stitched fringe" is just a string of 45-degree curves that I twisted around the perimeter.

The seat itself is just a scrap piece of aluminum I have (sitting on the bike in pic above), that will get a little chemical patina, and then be engraved on the CNC router. After that, I'll hammer some gentle rolls (to help keep me on the bike), and mount it. I think I am just going to do a simple flange and tab pivot up front, with hairpin springs in back.

The CAD curves, and a preview from the programming software.


I have an idea for a simple lower trim piece that would finish off the illusion of sophistication, and also serve as the tail light and turn signals. I can cut a, slightly sculptured, ring from a piece of acrylic that matches the shape, tapering from thin in front to thick in back, with LEDs embedded in it. Red in back and amber on the rear corners. Cut and engraved acrylic can be end-lit, meaning light directed into the sides will reflect in the cut portions. If I get the design right the light will be diffused but bright in back, where it's needed, and kind of fade away as it goes forward. Cheap trick. :D
 
#4 ·
This is a part with production intent, that I decided to to do now, rather than later. The cheapo handlebars were the weak link in the project, and had to go. These are going to be smooth chopper style bars, where there are almost no apparent controls. With electric this is way too easy - no clutch, and no throttle cable needed. The grips will be the same diameter as the this tubing, and the right hand grip will be the throttle. That GM TPS will be mounted in the "V", and a rod from the throttle will turn it. I'm not going to hide the TPS, as I want people to notice it so I can explain how it works. Production versions will be different, this is just the concept to promote one of my future products. Unlike traditional, capitalism, I am not going to be so secretive about most of what I do. I'll try to make my money by being first and/or best to market, and hope to contribute a lot of open source design stuff to the cause.


I'll chamfer these, weld, and blend, them next.

The front brake is going to be fly-by-wire. There will be a small lever - I think I am going to use the balled end of the clutch lever there - but it will be obviously too small, and also obviously not directly connected to the brakes. It will control a pot that will direct a stepper motor to apply the appropriate amount of pressure to the master cylinder; which will be mounted on the chassis somewhere. I want a stepper controlling the rear drum brake too, eventually, and ultimately with the ability to electronically control the bias, so that the front brake lever is the only brake control. Initially I might use this simple control method, but will move up to something like an Arduino.
 
#5 ·
Seems like a cool project. But I'm not sure that it's a good idea to trust a stepper motor and controller for the brakes. Perhaps there could be a "fail-safe" mechanism that would automatically apply enough mechanical spring pressure to the brakes to stop the bike safely and also function as a parking brake if electrical power is disconnected. Then the stepper motor could release the brakes or apply extra pressure under control by the rider.

There could also be some braking by using the motor as a generator and that might supply enough electrical power to apply the brakes in the event that the batteries are depleted. Maybe a few ultracapacitors could be added to provide the surge current you want and also absorb the energy from regen, but of course some of these things may involve some expense and may not be practical. Just some ideas...:)
 
#6 ·
Seems like a cool project. But I'm not sure that it's a good idea to trust a stepper motor and controller for the brakes. Perhaps there could be a "fail-safe" mechanism that would automatically apply enough mechanical spring pressure to the brakes to stop the bike safely and also function as a parking brake if electrical power is disconnected. Then the stepper motor could release the brakes or apply extra pressure under control by the rider...
Thanks and I agree. There is definitely a need for a fail-safe. What I'm thinking is an actual mechanical lever, positioned discreetly so that I can find it and use it the event of a "fly-by-failure". :eek::D With the front master cylinder and rear drum activated centrally, in the chassis, I can also have a mechanical lever that has access to them. Not ideal, but Squat is evolving into more of a concept bike than I had anticipated.




...There could also be some braking by using the motor as a generator and that might supply enough electrical power to apply the brakes in the event that the batteries are depleted. Maybe a few ultracapacitors could be added to provide the surge current you want and also absorb the energy from regen, but of course some of these things may involve some expense and may not be practical...
In the spirit of "concept", that would all be fun to experiment with - if not for the added expense part. I will put those things on the wish list, but don't really have plans to purchase a regen capable controller for it any time soon. Most of the initial fabrication will be nearly free, using leftover materials from other projects, and the power stuff mostly hand-me-down from Scrape. However, if the budget increases later... ;)




...Just some ideas...:)
Thank you - I welcome them. :)
 
#9 · (Edited)
I found these installation and wiring instructions for the little Curtis (here):
Curtis Model 1505 Speed Controller
Curtis Model 1505 Pulse Width Modulation 24 Volt DC Motor Speed Controller
The Curtis PMC model 1505 is a small, simple, low cost, unidirectional controller designed for electric bicycles, scooters, mopeds, trolling motors, pumps, and other small PM motor applications. It offers smooth, silent cost effective control of motor speed and torque. It has no annoying delay on acceleration like most stock scooter and bike speed controllers have. These controllers have strong electronic dynamic brakes as you let off of the accelerator, eliminating the need for a mechanical rear brake usually. 24 Volt dc, 20 Amps continuous duty, 80 Amps for 1 minute rating. Thermal overload protection rolls current back when unit gets hot to protect the electronics. Common 5k Ohm potentiometer throttle input.

  • Power MOSFET design provides silent high frequency, high efficiency operation which reduces controller heating, motor and battery losses.
  • Current limited to protect the electronics.
  • 3 wire 5k Ohm potentiometer throttle input.
  • Open wire pot fault feature turns off controller if any throttle wire becomes open circuit.
  • Under voltage cutback reduces output current as battery voltage drops below a preset level.
  • Keyswitch input to turn on the controller.
  • Simple installation with no adjustments required.
  • Quick connect terminals.
  • Easy to add an auxilliary Heatsink using 2" 6x32 machine screws'
Curtis PMC Model 1505 Speed Controller
CURTIS PMC MODEL
VOLTAGE (VOLTS)
1 MIN. RATING (AMPS)
CONTINUOUS RATING (AMPS)
TYPICAL VOLTAGE DROP AT 20A (VOLTS)
UNDER VOLTAGE (VOLTS)
1505
24
80
20
. 40
18










- Controls the speed of one or two electric motors.
- Requires a minimum of 18 Volts DC to operate.
- Requires a 5k Ohm throttle or potentiometer.
- Complete all connections prior to hooking up the battery pack.
- The key switch circuit must be "on" for controller to operate.
- The EPO circuit is optional. If installed the EPO circuit must be "off" for the controller to operate.

Note: The above Diagram is INCORRECT where it shows a 'Battery Current Meter'. This is a VOLTMETER connection, not a shunted AMMETER connection. The FULL BATTERY VOLTAGE appears across pins 1 and 2. Short or shunt them (I.E. put an AMMETER between them) and you will get a BLINDING FLASH as the pins vaporize.​
 
#12 · (Edited)
My obsession with antique clock domes returns. :eek::rolleyes::D This time, however, it's not a pie-in-the-sky idea, a possibility, or a mock-up - it's a plan in motion! :D

The little controller is actually supposed to be here tomorrow, and I found (and purchased) a small, used, acrylic dome on eBay today. I have a heat sink saved in my Watch List, and will pick up whatever supplies I don't have to make it soon. What makes this one a quickly achievable goal is the size of the components and experimental nature of the beast (Squat). The dome cost a tenth of what the other ones cost, probably even less for the heat sink, and there won't be massive amounts of heat to worry about, so cooling isn't such an issue.

For that I also purchased a clear plastic, 120mm, computer case fan, with blue LEDs! :D To make this a reality, all I really need is a chunk of thicker acrylic to cut the base plate from, some screws, nuts, bolts, and to fabricate some kind of mount.


On the subject of the cooling fan. The idea is to have it blow into the bottom of the housing, of course, and out through the heat sink. In addition to the area on the ends of the fins that is inside the housing, I plan to mill between the fins on at least part of the sink that isn't connected to anything - it bolts to the heat sink on the 1505 controller; the little aluminum block.

Wait 'til you see how it will be incorporated into the bike! :D
 
#13 ·
The Curtis 1505 was actually here yesterday but, for some reason, the mailman (USPS) arrived here at 8:41am, instead of his normal 10:30-11am, so I missed him. It comes back, along with the dome, Scrape's motor, and a couple other odds and ends tomorrow.

In the meantime, I have still been screwing with these handlebars! :eek::rolleyes::D My design projects usually have one or two key items that set the creative foundation for the entire project, so it's critical to get that right. With Squat it's the handlebars. They are what ushered in the integrated, passive, tech theme.

These are the individual pieces for the risers.



Then welded. I MIG'd the washers to the mounting studs, and tacked the tube sections to the washers with the TIG. I'll probably TIG weld those to cut down on the grinding.



On the bike.



A couple beauty shots. First a silhouette, in front of the welding area dock door, and then a knee-high-to-an-ant shot with the welding curtains in the background.

 
#14 ·
In all the hubbub over Scrape's motor, I am just getting around to posting pics of what I have been drooling over since Monday morning - Squat's flux capacitor drive!!! :D The little 1505 and acrylic dome have been in my office since then, fueling my creativity. The fan is on the way (from China), and I expect to purchase a chunk of acrylic to machine the base from soon. Naturally, I have some crazy, crazy, ideas brewing... :cool::D







Think this thing could be hacked to run at 48 volts? :rolleyes::D
 
#15 · (Edited)
I could not find a schematic and I couldn't even find this controller model on the Curtis website. They all seem to be 1200 series. What I found was this:
http://www.cfnet.net/tm/1505.htm
http://cafeelectric.com/curtis/Curtis_manual.pdf (1200 series)

There is a PDF site that supposedly has a schematic, but I've found that they ask you to join some sort of gaming or file sharing network, and I'm not "game" for that:
http://www.imarkswebs.com/bk/curtis+24v+controller+diagram/

The following thread shows a rough schematic and mentions using the smaller controller with higher power MOSFETs:
http://www.diyelectriccar.com/forum...ontroller-design-sg3524-and-tc4420-13763.html

And this search brings up some threads that might be helpful:
http://www.diyelectriccar.com/forums/forumdisplay.php/controllers-36p44.html

If you can trace out some of the circuit and identify the MOSFETs and power components such as the large capacitors, it might be possible to rework it for 48V.

It appears that there is one unusual IC on the board, a SGPMC-98500, which is some sort of PMOS DC motor controller:
http://www.seekchip.com/icstock-S/SGPMC-98500.html
 
#17 ·
A couple developments:

One, a potential new volunteer visited the community workshop yesterday, and expressed interest in helping with the vehicles. He is an automation engineer, who is also an EE, and expressed interest in helping with some of the electronic/electrical stuff. If you've been following any of my threads, you'll know that I haven't had the best luck in attracting and keeping electronic types, so I am cautiously optimistic. I am going to start with some of the ideas I have for Squat, and if he's still around progress to DIY controllers, rewinding motors, etc... :)

Two, I had to let the theme gel a little, but have been looking for a direction for final finishing on Squat. It's kind of important to figure out on scratch-built/nearly-scratch-built vehicles, because materials and component choices have to be inline with what the final goal is. The retro-futuristic theme, like I was pursuing with PackRat, wins out here again; with a bit more bias towards the future.

  • For some reason, I am really into the blue LED lighting thing. The fan was chosen, in part, because it has them incorporated in it, and the eery sci-fi glow in the clear plastic is exactly what I see in my head for this bike.
  • I want stuff to light and glow all over it - but done as tastefully as possible. So, I'll probably concentrate on illuminating things that make power or provide an interface.
  • I had been planning traditional chopper/hot rod stuff for the seat and grips, but now am thinking about using them for the blue glow. I might try cutting my seat from the blue acrylic I have and making the TPD logo an insert piece with LEDs, so it end lights all the engraving, and the edges. So, if it works properly, the shiny blue plastic seat will display an outline and pattern when the bike is powered up.
  • Similarly, for the grips, I can laser etch pieces of acrylic tubing (CIF's laser has a 4th-axis rotary attachment), and end light them, so that the pattern glows when powered up. I'm trying to decide whether to use clear tubing for contrast, or matching blue.
  • The "flux capacitor" (controller) housing will of course have blue LEDs in the fan, and I am considering a miniature chill plate instead of the finned heat sink, with a coiled coolant line going to the chill plate - of course highlighted by blue LEDs. :D I thought about some type of clear lines, and tinting the cooling fluid blue but that brings up a lot of complications (how/what type of clear tubing to heat and form, how well will it tolerate the heat, etc).
  • This might all sound crazy, but it is honestly the easy way out, for me. Sticking piece of acrylic in the laser and poking some LEDs in it is simple, and lightning quick, compared to fabricating and machining my normal metal parts; not to mention the acrylic and LEDs are dirt cheap, compared to what I would spend to do all this aluminum...
  • Finally, for now, I was originally planning on candy-metallic burnt orange or lime green paint, using the LED lighting just for highlights, but "blue" has taken over. I am now thinking about candy blue powder coating for the frame and swingarm, and probably some mixed natural and blue anodizing on the aluminum stuff, to give the whole bike that futuristic blue glow.
More to come... :)
 
#18 · (Edited)
Have you considered using RGB LEDs and a controller that can be set to produce just about any color and brightness? I think that could be way cool, and it could also be set up to change in response to speed, acceleration, or other parameter.

You may need to make sure the blue lighting does not violate laws which sometimes disallow colors that are used for emergency vehicles (assuming you want this thing to be street legal). The multicolor scheme solves this so you can use any combination and change it on the fly if needed.









 
#19 ·
Have you considered using RGB LEDs and a controller that can be set to produce just about any color and brightness? I think that could be way cool, and it could also be set up to change in response to speed, acceleration, or other parameter...
Thanks for posting the videos Paul. My goals are for more subtle accents. Lighting that highlights the features of the bike, rather than becomes the attraction, hence my desire to use hidden LEDs that end-light the engraving and edges of the acrylic, and add a subtle glow.

I do want to use an Arduino controller eventually though. I want to make the lights pulsate and dim, to highlight things that are going on with the bike (power up/down, charging, nearing battery depletion, etc). I also want really passive "gauges" incorporated into the bike, so there I would probably use the color change idea. For example, a small LED or strip of LEDs that starts green and normal brightness, but goes yellow, then red, and progressively brighter - and probably flashes - to indicate SOC. It won't be as intuitive, or identifiable, as a normal gauge but then again Squat won't be used like a normal bike...




...You may need to make sure the blue lighting does not violate laws which sometimes disallow colors that are used for emergency vehicles (assuming you want this thing to be street legal). The multicolor scheme solves this so you can use any combination and change it on the fly if needed...
I've noticed people riding here with all sorts of LEDs, constant on, flashing, dancing to music, etc, while riding, so I guess Ohio is pretty forgiving with motorcycles.

I doubt a cop would even notice most of mine, because it's so subtle. My azz and hands will cover most of the seat and grips. The controller will have a subtle glow, as noted, that will be partly obstructed by my legs, etc, etc...



On this note: I had some new thoughts on the controller chill plate/fluid idea. Fiberglass sleeve supposedly goes transparent with epoxy resin. I should be able to print the core in ABS, slip the sleeve over the plastic coil, wet-out, heat shrink tubing, cure, remove heat shrink, dissolve ABS in acetone, and have a clear coiled flow tube... :D

I need to get some glycol, find a dye that will work, and something liquid that will not mix with the glycol and form little bubbles in the fluid, so it can be seen flowing through the tube (think lava lamp). :D:D:D Again, very subtle, but it serves a purpose in showing how the cooling system works. Wait'll you see my radiator.
 
#23 · (Edited)
As soon as Scrape's motor is wired up (hopefully later today) I will turn my attention back to Squat. The goal is to have both bikes running for the Columbus Mini Maker Faire, in three weeks. :) That's the event I debuted Scrape at last year. This year Scrape will be faster, better, and will have a younger sibling with it.

Last week, I found a piece of 12" I.D. steel tubing at the local recycler, for $5, so I can get the chassis together. I grabbed my pencil and coffee saturated notebook this morning to think through what I want to do, and found the opportunity to get really creative. I, obviously, also had a little fun with it in Photoshop...


So, if you're not fluent in chicken scratch, here's what you're looking at. After I weld the 12" tube in to create the battery box, and now main frame section, I will splice a piece of square steel tubing into the old frame, just behind the neck, running down to the battery box. Then, I'll cut the old frame completely out, and sculpture the new "backbone" and seat mount with fabricated steel sheet metal. Somewhere in that process, I also have to create the matching sculptured brace on the bottom of the swingarm. For around twenty-five bucks, and a few hours of labor, I will have an organic EV display piece/modern chopper; instead of an old Honda. Of course, that's my coveted clock-domed, flux capacitor drive in place of the fuel tank.



My new electronics guy had a great idea for the battery box. I had been planning to put smoke-tinted acrylic or polycarbonate "windows" on it, so people could see the batteries. His point is valid, that even with the best batteries they're still kind of visually boring, to the average Joe. He suggested this:


I said - absolutely! Imagine the Bat-T logo in the center and perimeter LEDs disappearing into space. To complicate things, I want to do an Arduino controller that will make the perimeter LED lights spin forward when throttle is applied and backwards when in regen - to actively show energy leaving and returning to the pack.

Sparks fly this week... ;)
 
#26 ·
My new electronics guy had a great idea for the battery box. I had been planning to put smoke-tinted acrylic or polycarbonate "windows" on it, so people could see the batteries. His point is valid, that even with the best batteries they're still kind of visually boring, to the average Joe. He suggested this:


I said - absolutely! Imagine the Bat-T logo in the center and perimeter LEDs disappearing into space. To complicate things, I want to do an Arduino controller that will make the perimeter LED lights spin forward when throttle is applied and backwards when in regen - to actively show energy leaving and returning to the pack.

Sparks fly this week... ;)
I really like that idea, very showy and absolutely idea for what you are doing. :)
 
#28 ·
Not sure my chicken scratch frame design is going to happen. Many great ideas are worthy of consideration, not all of them are feasible to actually pursue. :) I welded the big 12" battery box tube, and the original front down tube I had planned and already underway, into the frame. That was the original plan, and it looks pretty darn good as it is. When I weigh finishing up what I have here and moving on to actually making it run - against cutting and grinding, and cutting and grinding, and cutting and grinding, to make that little sketch a reality... :rolleyes::D

I'm thinking that a hybrid of the two ideas might be the best route. Keeping the existing frame, but lopping off the rear section and floating the seat on a sculptured, organic, pedestal; sort of like the sketch.

Pics later...
 
#29 ·
So here's today's progress, and the original bobbed Honda frame plan. Battery box section of the frame, and front down tube, welded in. I still need to finish welding the two-piece front down tube together and blend it, but it's fully welded to the frame and battery box. It could have been a one piece tube, but I had those two bends laying around...



Tomorrow, I will probably fit and weld the motor mount. Then I just need to pull the rear wheel off and make the sprocket adapter and it will be ready to wire up and run.
 
#32 ·
I welded the motor mount on today, and reverse engineered the original sprocket mounting pattern and center hole, and the new sprocket mounting pattern, then cut a test adapter in acrylic on the laser - fits perfect first crack. Pics of all that soon...

In the meantime, I have been working on the flux capacitor drive. I modeled the base that mounts the fan and "thrusters". :D I need to stare at this and make a decision really quick, because if I'm going forward with it I need to get the acrylic block here soon. The fan is trimmed of its mounting flange on one side, and mounted to the base plate. The blue section is an acrylic flange bonded to the dome, that mounts the dome to the base plate. Finally the aluminum thrusters mount to the back of the base plate to release the hot air.


 
#33 ·
Almost there. The sprocket adapter is cut and works perfectly. Honda used a pin drive setup on the little 400, which is pretty cool, except for the fact that the sprocket is held in place, laterally, by a single external retaining ring. It's a beefy one, but I am glad it's on my low-power machine...

The pins needed these pockets in the adapter to self lock, as the nuts are tightened on the other side. A more elegant solution, Honda engineers, would have been a single piece with four pins; but I accepted the challenge to get my reverse engineering, of their overly-engineered solution, right and make the individual pins work - nailed it. ;)



The pins fit in these drive bushings, which engage with the rubber drive cushions, hidden behind the steel shims, and there's another miscellaneous plastic piece that caps it all off before the sprocket carrier goes on - lots of extra little pieces...:rolleyes: I also need new rubber drive cushions - there's a bit of slop.



I had to cut a bushing, the small aluminum washer in the center, for the retaining ring to work with my new setup. Luckily it was exactly .250", so I just machined the internal and external diameters. It would have been a nice little lathe project except for the fact that the cross-feed ball screw of our lathe is out for repairs, and it needed small clearances cut for the nuts. I didn't catch those until it was off the CNC, and ended up manually milling them (a bit too large). I will eventually machine this piece again, probably from stainless. I also bought bolts that are a little too short - will replace them soon, and use locking nuts.



Then, just as I thought I was ready to put 12 volts to the wheel and see it spin under electric power for the first time - I discovered that the chain is toast! :( At first, I thought the guy was wrong about the sprocket being for a 530 chain, but remembered checking that as soon as it came in. I noticed the chain would fit perfect in places, but not conform on the bottom, unless I forced it. It was almost 2am, at this point, and took me a while to realize it was literally contracting and expanding lengthwise!!! The plates are worn so bad, you can literally move some of the links around a sixteenth of an inch on the pins!!!!! :eek: There's no way I'm running this on my aluminum sprocket, plus I need to cut a little chain clearance in the swingarm, so the day (night) was over. So close...




I really like how this bike is turning out. It has a bit of old school, American cruiser/chopper, mechanical feel, that will be blatantly counterbalanced with the futuristic, fantasy, drive systems. It's exactly what I was after with PackRat, times 100. :D
 
#34 ·
It lives! I just took the first ride around the shop on Squat!!! :D Just like Scrape before it, I was using a single 12v battery (one of Scrape's scooter batteries), this time just touching the wire on the terminal with one hand (can't find my starter button), hanging on with the other, feet flailing. :D I even let one (motorcycle riding) member of the community workshop take it for a little spin.

I am surprised it's as "fast" as it is, with the steep gearing (5.8:1). That, combined with the utter lack of weight, means it definitely feels snappier than Scrape off the line. Not quick, or anywhere near startling, just peppier. The "top speed" was still decent - everyone who watched was surprised, again, that it was as fast as it was with one small 12 volt battery. I think it's going to be a nice little urban cruiser with 24 volts. :)

I also have no brakes! :eek: I was literally using the Flintstones method to stop. :D I think regen is going to work really nice, and the electric front brakes will be mainly for balance, and to come to/hold a complete stop. That's backwards from how you're supposed to stop on a motorycle, but hey my first mini bike did 35mph, and only had a drum brake on the rear wheel. :D

Video when I can get someone to shoot it. I made my goal of having it functional for the EV & Hybrid Meetup tomorrow, and have two weeks to make it as nice as possible for the Mini Maker Faire...
 
#36 ·
Well done on the first ride milestone!:)...
Thanks Woody! :) This little bike is a blast! I can't wait to get the controller wired up, with the little AGM pack next week.




...That big cylindrical battery box keeps making me think it will be a short 12" motor sitting in the frame.....
:D
:D
 
#37 ·
My acrylic plate arrived today, and I wrapped up the revisions to the housing base - so it's time to cut! :) I didn't like the square base sticking out under the dome. It was only there to accommodate the factory mounting holes and flange of the computer fan. Then, I remembered that I don't normally do "factory". :D We tested bonding a piece of the fan housing to a piece of acrylic and, when that was successful, I was free to play. The fan will be trimmed down, and bonded to a new mounting flange (the blue ring), allowing me to make a round, organic, base that flows off the bottom of the dome.



Here's the acrylic block, with the little bonding test piece, and the new, laser-cut, mounting flange for the fan.




The blue base is just for effect. It's a small color highlight in the maze of clear acrylic. It's parallel with the fan's, four, blue, LEDs so they'll end light it and enhance the blue glow - I hope... :D
 
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