E-Bike XB-502 conversion project

[ElectricGod]

The chain line is finally done! It shouldn't have been this hard, but it was. I made 3 wood mock-ups and tried different places on the swing arm. All of them had issues. I finally went with a smaller roller and that fit in this location nicely and solved all the issues I was having with running into the swing arm with the roller or the chain. I've spent several days now trying different rollers and tensioner locations. It took a loooong time to get the chain line right, but it's silky smooth, dead straight and doesn't interfere with anything now that it's done.

The final tensioner took several hours to make and tweak, but it's rock solid and works perfectly. The 3 holes need to be elongated so that it will slide up or down the swing arm a little as the chain stretches and it needs to be painted. Otherwise it is finished.

This location gets the return side of the chain away from the swing arm. Having the chain graze the swing arm was causing me lots of problems.

 

[SlowCo]

Why the chain tensioner when you can just slide the rear axle further back?

 

[ElectricGod]

There we go...slotted.

 

[ElectricGod]

Why the chain tensioner when you can just slide the rear axle further back?

For several reasons, one reason is because of how the brake caliper mounts. One end of the bracket is trapped on the axle.

See that 8mm pan head bolt just above the brake caliper? It threads into the swing arm and then threads into the bracket for the brake. Even though the axle has a tensioner on it, the 8mm bolt won't allow the axle to move since it's all locked together.

And then finally, the chain needed to be lifted up so it doesn't drag on the frame right below the motor. Notice how the return side of the chain just grazes the frame? It makes a good bit of noise and of course wears on the frame. The chain tensioner solves this issue.

The chain is lifted away from the frame where it grazes the frame as the chain passes over top of it.

 

[SlowCo]

Ah, now I see!
I've been following some of your threads and like the work you're doing. Good luck finishing this.

 

[ElectricGod]

Ah, now I see!
I've been following some of your threads and like the work you're doing. Good luck finishing this.

Thanks!

Lots of people read my threads and then PM me about their builds. I've gotten requests for help from all over the world. Quite often we stay connected for many months as I help them work through their issues. A few months ago I was working with a guy from your country. Right now I'm working with 3 people from NYC, San Francisco and Romania.

 

[ElectricGod]

I've been busy with LED's and chargers and batteries. I also got the Pantera moped running and sold it off for $400. I had a bunch of SLA's and an old controller that went in it to get it running. Cost me nothing but an hour to get it running again. Anyway, it's been a while since I made any progress on the moped.

I got a new throttle for it and installed it, brake lights are hooked up now and the XHP70.2 headlights are in place. Since I've never had a working throttle on here before, I've never known which way the motor turns. Well it's backwards...go figure! That's pretty easy to straighten out. There's always something I suppose.

The headlights have been done for a good while. They were waiting on free time to get them installed and wired up. I took the lens ring off and used that to figure out where to cut out the headlamp shell for the new LED lights. I also got better reflectors which needed some slight massaging to make them fit the LED shells, but that's all done now. The lights are glued in place by their front lens rings. The backs of the lights sit on some plastic parts inside the moped.

Dashboard.

Rear running lights and tail light.

Brake light.

Front running lights.

These handlebar lights are actually 2 sets of LEDs...yellow and white. I really wanted to use the white LEDs for another set of running lights and the yellow ones for flashers, but they wash each other out so they all became directionals instead.

Low beams...they are cheap Chinese LED headlights, but plenty bright enough.

Because of the shutter closing down, it's impossible to show how bright the high beams are. Suffice to say, they are plenty bright!

 

[ElectricGod]

Busy busy busy!!!

Finally got back to the moped again...

I've had these parts partly made for several months now and finally got them finished up tonight. It's a piece of aluminum rod that's about 1.5" long. The bottom is narrower and is threaded with M6. The the wider portion as seen here is threaded with 1/8" NPT on the outside and M6 on the inside. This allows me to have a single stud that threads into the frame, then thread on a nut with 1/8" NPT threads to hold down the plastic front sections and then finally to place the deck on top of all of this and hold it down with 2 M6 screws. I'm sure there's some other way to do this, but I had all the taps and dies and the aluminum rod so why not? The top of the NPT threads get pretty much destroyed by the pliers when I thread down the stud and snug it down. Oh well, I'm not using the threads on there anyway.

And finally a secured deck on the moped! There's a nice gap underneath the sides that will get sorted out next. I need to get some security torx screws in M6.

 

[ElectricGod]

The motor spins backwards ATM and I don't have any black paint for the deck so it is currently primer red. I have grip tape to apply to the top side of the deck. The deck needs some curved wood pieces made for sealing up deck to the moped body and then this machine is DONE.

 

[ElectricGod]

Don't know what happened exactly, but I blew out several mosfets in the controller. I was messing with motor phases to get the motor running forward and I picked a phase combination that made the motor shudder and then the controller was dead. I guess phase amps must have been crazy high or something. That was fun taking everything apart to pull the controller! I had no intention of running at higher than 82 volts. Since I had no IRF4115's and lots of AOT290's, I swapped all of them over. It's back running again and now I have a full telemetry module in the controller too.

 

[John in CR]

What happened to the original deck? On the European legal version I got my hands on, the deck was about the best part of the entire scoot...decent plywood shaped, sealed, and covered with a rubberish mat.

If you're planning on using it on your long commute, keep an eye on the front end. One of my front springers wore out and broke while riding. Luckily I was going slow when it completely separated and paid attention to the strange handling immediately after the speed bump.

I hate that front handling, so I've been looking for cheap parts scooter to hack the front off and put on my little commuter rocket to make it a lot safer.

 

[John in CR]

Don't know what happened exactly, but I blew out several mosfets in the controller. I was messing with motor phases to get the motor running forward and I picked a phase combination that made the motor shudder and then the controller was dead. I guess phase amps must have been crazy high or something. That was fun taking everything apart to pull the controller! I had no intention of running at higher than 82 volts. Since I had no IRF4115's and lots of AOT290's, I swapped all of them over. It's back running again and now I have a full telemetry module in the controller too.

I use alligator clip jumpers to the phase and batter wires when figuring motor wiring. That way there's never enough current flow to blow anything unless you let something short together. Plus it makes swapping wires quick and simple.

 

[ElectricGod]

Don't know what happened exactly, but I blew out several mosfets in the controller. I was messing with motor phases to get the motor running forward and I picked a phase combination that made the motor shudder and then the controller was dead. I guess phase amps must have been crazy high or something. That was fun taking everything apart to pull the controller! I had no intention of running at higher than 82 volts. Since I had no IRF4115's and lots of AOT290's, I swapped all of them over. It's back running again and now I have a full telemetry module in the controller too.

I use alligator clip jumpers to the phase and batter wires when figuring motor wiring. That way there's never enough current flow to blow anything unless you let something short together. Plus it makes swapping wires quick and simple.

I already have 5.5mm bullets on everything. I figured it out...2 bullets weren't closed up all the way and they shorted together. I killed 17 of 18 mosfets. Once the mosfets were replaced, the controller was back to running again. Oh well I wanted AOT290's in it and it had IRF4115's. A costly way to swap out the 4115's, but the job is done now. LOL!

 

[ElectricGod]

The motor controller is fixed now...installed AOT290's. I also added the latest version of the telemetry module with dual temp sensors bonded to the mosfets. It's all working and in good shape again. Since I was repairing the motor controller, I also realized I made a couple of snafu's in my wiring. All the wiring i nthe EV goes to a terminal block that I had forgotten about. It was stuffed down next to the motor controller. nothing is water tight in this position and water getting in that terminal block would be a disaster. I am moving the terminal block to inside the battery box. I also moved the power distribution block into the battery box and extended the power wires to the controller to the new location. This will fix several issues at the same time with water intrusion into wiring and also make the motor controller MUCH more accessible without major surgery...like I had to do to pull it out.

Blowing up the controller was not something I wanted to have happen, but it exposed design flaws that I had forgotten about and had intended to fix months ago after everything was working. Well they are getting fixed now before they become problems!

 

[kiwifiat]

Nice job on the conversion, I'll be interested to hear how it goes with the big block. The big block runs really nicely driven by the Lebowski controller.

 

[ElectricGod]

A bit more rework done...

I've moved the wiring that was exposed to inside the battery box. I also moved the power block inside.

Power to the controller has been extended to the new location and upgraded to 8 awg.

There used to be a piece of sheet metal welded here. I cut it out and filed off the welds so the motor controller could go here. The controller will get much more air flow and is lots more accessible. I still have to remove the seat and storage box. It's held in by 4 screws. The screws that hold down the controller are underneath, but that's lots better than disassembling the entire back section of the moped to get at the controller.

 

[ElectricGod]

THe XB-502 is on the charger right now. It's all back together again and ridable. The deck still needs some work, but I'll be able to ride it tomorrow.

 

[ElectricGod]

After last night getting things all put back together, I made some controller setting changes to account for an 82 volt pack and went for the maiden ride tonight. I started at 123 phase amps and that worked pretty good, but the motor felt a little tepid so I bumped it up to 166 phase amps and then acceleration felt pretty decent. I'm going to bump that to 180 amps for the next ride.

I charged last night to 76 volts since it had never been charged before. Tonight I went for probably 30-40 minutes of riding and that dropped me down to 73 volts when I returned home. This was the maiden voyage and for the most part, I'm pretty happy. I don't know what happened, but the front wheel fender has deformed and now when the front shocks compress, the fender drags on the tire. I took it off and went back out again. The roads are dry, so who cares for now. I tooled around town doing mostly 30-45mph. After a while I was getting used to how the moped handles and wanted to see what it had to offer. I was riding on roads that generally see cops pretty often and so I headed for a road that I have never seen a cop on. I then cranked the throttle to WOT and held it there. Acceleration was as good as or better than the cars I was passing who were all doing 40-50mph and I topped out on level ground at 55mph at 73 volts while sitting straight up. In a tuck, I bet I'd pick up another mile or 2. I'm charging right now to 100%. I'm really curious to see what 82 volts gets me. 60+ I bet!

Other than the stupid fender, everything worked perfectly. I want to adjust my XHP70.2 headlights up a little. They point too close in front of the moped and not down the road enough. I want to rewire the low beams so they are on in high beams too. Other than finishing up the deck, it's perfect. The motor and drive line is sooo quiet! I need mirrors for it and I think I have a set...somewhere...maybe.

This is the reading on my GPS speedo. I held 55.3mph for just over 2/3 mile. Yeah 26.6 miles between 2 runs tonight...not bad and just 3 volts drop in the pack.

This is the motor temp at 166 phase amps and my battery voltage after a few minutes of recovery. Under load at 55mph I was looking at 73 volts.

Where I live the state law says that an unlicensed moped can drive at 40mph max. I've added this stealth 3 speed switch under the front edge of the seat. Low is 25.2mph, medium is 38mph and high is maximum everything...or last I checked...at least 55mph. If a cop pulls me over for exceeding 40, I'll flip it to medium and then tell him there has to be a mistake since my moped doesn't go that fast and tell him to clock me again. Since WOT in medium is 38, he'll walk away scratching his head and I'll go away with a giant smile on my face.

 

[ElectricGod]

what's totally brilliant about this build is it looks pretty much factory...like it's unmodded in any way. You'd have to know what this moped looks like in detail off the factory floor to know it's sooo NOT factory anymore. When I got it, it ran at 48 volts on 4 SLA's. It had zero ability to get moving on it's own. You literally had to kick off multiple times to get moving fast enough for the motor to get up enough speed to carry you on it's own. Even over watted, it could get going on it's own. The motor was weak and the controller even weaker. With a wind at your back, it topped out at 26mph and took a good minute+++ to get there. Now, 26mph happens in a couple of seconds and it is not close to being done going faster.

Big giant grin on my face!

My next project is the RMartin moped. Right now it tops out at 50mph and weighs 4X more with all the SLA's in it. This 50cc sized moped makes that thing look slow.

 

[ElectricGod]

GAWD! 2 months since I got to think about doing anything to finish this up.

 

[ElectricGod]

Close to getting back to this...

The Currie is getting some updates to it and I'm doing some work for a friend. Once they are done...

 

[ElectricGod]

Geez...a lot has happened since I got to think about working on this beast. Moved to a new house, finished up the Currie scooter modifications, completed 2 projects for friends, worked on another friends blown controller and various other smaller projects.

Finally getting this back on the bench again to get it closed up the rest of the way. Last I remember, I needed to connect the new throttle and finish the deck. I think I needed to modify the chain tensioner so it can slide and be adjustable. It's currently working in 1 position only and otherwise needs to be completely pulled off to get slack in the chain. I've also modified a smart BMS for it. Currently it uses a couple of 50A, 20S dumb BMS and the smart one is good for 20-28S and 300 amps.

I've never tested it for range. Never had it on the road for more than 5 or 10 miles. That will be next...maroon myself 10 miles from home! My expectation is with 32Ah I should get around 15-20 miles at max power the whole way. With more casual riding, something like 25 miles. The battery bay is only about 80% full since it has 16ah LIPO packs in it. There's lots more room in there if I build a pack with 18650's that fits the space. I bet I can get 40-45Ah in there if I build it from 18650's. There's also a storage space under the handlebars inside the front cowling that I want to expand a good bit and put another 32Ah in there. I should get 50-60 miles range with 64Ah of LIPO and keeping up with traffic...aka 40-50 mph.

The shocks on it are almost worthless. The "gas" part does not work at all. They are just springs. Something went wrong on all of them and they don't damp at all. Cheap Chinese garbage! I've found not terribly expensive adjustable gas shocks. It needs fronts and backs.

 

[ElectricGod]

I've spent some time over the past few days...

The throttle is hooked up, all the lights work again, new telemetry module is in the controller and working great, the motor spins up, it's ridable again.

I did find a problem with some of the factory electrical. Most everywhere, I stripped it all out, but chose to leave the wiring to the tail lights in-tact...bad idea...because it has issues. If the lights are off and I hit the brakes, the brake light comes on, but so do the other rear lights, but dimly. There's some sneak circuit in there back feeding power to the rest of the lights. Oh well tear it out and do it right.

 

[ElectricGod]

A bit more progress today....

The scooter is all closed up and the deck is coming along nicely. I got some M6 stainless stand-offs to use for securing the deck. It worked out a lot better than the crappy aluminum stan-offs I made a long time ago. The deck is now secured with security torx.

The XLR charging port is gone now and replaced with an XT90. I'll make a weather cap for it tomorrow.

These are the new front stand-offs. The washers fit that rounded area and that serves the same purpose as the square nut on the aluminum stand-offs. THey hold down the front cowling that has mount tabs at hese 2 stand-offs. The aluminum parts were not that great and the threads on them were quickly getting messed up. The new ones are all stainless so they ought to be much stronger and last.

I need to buy more paint so I can finish the deck and then cover it in grip tape.

I taped paper over the gap between the deck and the side cowlings so that tomorrow I can cut wood to this shape. The wood parts will be attached to the underside of the deck and get sealed to the battery box. with closed cell weather stripping.

The contactor is now tethered to the scooter. It probably would be better if it could still be removed, but this way, if it gets bumped off somehow, it can't go bouncing down the road. I'll probably come up with some kind of quick release later for it.

 

[ElectricGod]

I took the scooter for a ride yesterday to test it out on longer runs. I'm not exactly sure how far I got since I shut it off multiple times, but I rode around for a couple of hours before I ran out of battery. Might as well run errands while I'm testing the scooter. I was riding most of the time at WOT just to see how well it held up and of course it did great. My top speed was 58.4mph. I had no problem keeping up with cars even on a local highway where the speed limit is 55. Something I was curious about is how much speed I would lose going from 82v to 64v. I never tried topping out when it was fully charged. That 58.4 mph was at about 79 volts. At the point were the BMS was dropping out or 69 volts 50mph was still doable. Battery sag at nearly fully charged was less than 1v. At the point where the BMS cut out, I'd see sagging of 3 or 4 volts.

I did find 2 small issues.
1. The radial fan on the motor was loose. Apparently I forgot to tighten the set screw on it. The motor never over heated, but it could have run cooler too.
2. The controller seemed like it was in a decent amount of air flow, but in riding around it warmed up to about 150F...warmer that n want. I'll have to figure out how to duct air flow into the controller.
3. I've purchased new shocks for it. The factory shocks are garbage. This ride really made it clear how much I need to replace them.
4. I'm not sure if braking will get better or not. It's not that they are not working. The brakes work fine, but I think I want a bit more braking power. It feels like it takes too long to stop and I can't break hard enough to skid. I'll hunt around for larger rotors if I think they are too weak.

A couple of 12v blower fans pushing air into here would do the trick. I have several. It's too enclosed up inside here to get decent air flow and no air comes off the tire either with the wheel guard in the way.

I upgraded a 20S BMS for this EV some time back, but never got around to installing it. I knew the dumb BMS's I had originally used were fine, so I left them alone. However, yesterday while giving the scooter the long run test, I was looking at 69 volts and the scooter kicked out. It was obvious the BMS had dropped out since all power stopped. All I had to do was let off the throttle and power came back a second later/ My assumption was that a cell or 2 was low and tripping the LVC in the BMS. I walked it home...about 2 miles since the BMS would not allow me to ride home on the remainder of the pack. When I got home, I checked all the cell voltages and none were below 3.5 volts. The BMS should not have tripped. It was time to swap in the smart BMS I had upgraded for about 300 amps. I'm balance charging from it right now. All cells are staying pretty close as they charge. They are currently 4.08 to 4.10 volts and pack voltage is at 81.77 volts according to the smart BMS. It's a fairly good fit on top of the battery pack.