2WD Electric Yuba Mundo Build

Hi, I just wanted to say your build and documentation is Great! Thanks for posting, I have used some for my current Mundo build (Controllers mounting) I am working on. Your build is the go to guide for the Mundo.
 
So - I'm hopelessly behind in posting on this build.... the bike has 11K+ miles on it and still running strong, so it's clearly into the tweaking and incremental upgrade phase of life.

Anyhow, last summer I decided to add brake lights to the bike. I had earlier looked at and purchased an off-the-shelf mechanical motorcycle brake switche to trip with the disk brake cable pull, but the whole strategy was just too fragile and Rube Goldberg.

genericChopperSwitch.jpg
So - as much as I didn't want to revise the pile of custom wiring, I took a look at the drive-it-from-the-ebrake-signal problem and realized it was a pretty easy project. Using a pretty standard microprocessor relay driver board (very tiny) got the job done PDQ. I stuffed it in the headlight housing so there were no new mounting issues.

I was going to post up the details here, but posted up the complete bike lighting details in an new post >>>here<<< where it might get better visibility for other builders.

The only twist on the generic circuit in that post is that I use only one live ebrake to the V3 so I can hold the bike in place on inclines and goose the motor for getaways. With two live ebrakes, the motor is dead until both are released. So - I wired the unused ebrake to drive the brake light circuit. This is handy since I can choose to light the brake light or not for on-the-go slowdowns by using only one or the other brake. This is not a big thing, but not getting other drivers in a tizzy over very mild braking can be a Good Thing.

While I was fiddling the headlight housing, I also wired up the unused daytime running light in parallel with the existing front strobe. The incandescent lamp was exchanged for a plug-in LED replacement unit from SuperBrightLEDs. This flashes the whole headlight reflector with a really white light, but in an inoffensive way. It's much more noticeable than the original 3-LED medallion light (which remains hooked up and working). Highly recommended for those going the bobber light route.

View attachment 1
The tiny opto-relay has a small square of flexible cutting board under it to protect the traces and got a sleeve of heatshrink to package it all up. The outputs have handy screw terminals and a 4s balance lead from eBay hooks up the input pins nicely. Here's the various modules ready to be stuffed into the housing - only the opto-relay is really new, but it's definitely a bit of a puzzle to get everything properly aligned to fit.

15_AssembledComponents.jpg
Anyhow - the brake light completes the 'standard' lighting suite. After years on a motorcycle I certainly wouldn't treat any lighting as a guarantee of safety, but anything that changes the odds in my favor gets the nod no matter what the game... :D
 
WOW! Fantastic build and what a resource for dummies like me absolutely brim full of gems of information - beautifully documented and much appreciated :D
 
Really fine read. Appreciate the quality and detail of your work, and the clarity of your thought process.

*edit, yep, out of 20 words I got one wrong.
 
Hi Tek,

I used your combination of X.3 trigger shifters and the Magura throttle with short bike brake levers, and it works fine. The front is hydraulic and the rear is a Shimano XT lever and caliper for the rear rim (frame has no disc mounts), and two or three fingers is plenty. I also had to take a bit off the inside of the long trigger to get reliable return. More in the Bonanza thread.

I also tried the Domino throttle and was unable to find enough clearance at the right angles. So the Bonanza will stay Magura throttled. Putting two PhaseRunners on for 2WD, should be sweet. Have a 72V pack coming, BMC V4TT front and 9C 6x10 rear.

Great build here and beautiful custom aluminum bracket work!
 
hey Alan-
Glad the Magura/X3 combo worked out for you. I was thinking of trying a Domino on a lark and was wondering how it might fly with the X3 - good to see you already looked into that. There's no doubt that the Magura is not a top of the line motorcycle-quality throttle, but I have no problem with them - I actually like the long throw and they've never failed rain or snow for some 13K miles, so what the heck...

I've been following your Bonanza thread - it's coming together nicely... :D

I was just talking with Justin this week about your non-ferrous saw blade remarks in that DIY Phaserunner Heatsink thread and remembering back to our posting exchange about those blades in this thread back in 2012. Time does fly...
 
Yes, time flies, and lots of good experience related here and there.

I had no previous experience with trigger shifters (till I got the RidgeRunner, which has the Shimano type), so good to get some starting suggestions to try that had some chance of success. These are inexpensive enough.

I did damage the front trigger shifter by shifting it with the cable loose, and it jammed up. I took it apart to figure out what happened, and the loose "end" of the cable inside got bent and jammed. The shifter is not damaged, but the cable is. However, I've no idea how to reassemble one of these shifters, parts popped out when I opened it, which I expected, but I wanted to understand what happened. So I just bought a second set and now I have a spare rear shifter, and spare parts for the front one, for $23 Amazon second day. :)

The Domino throttle is very nice, slightly less throw, softer grippier rubber, a switch on release that might be useful, but the body is larger diameter. There's a section that has a cut for clearance, it might work out, my first tries did not, but since then I've had to rotate things some so I should look again and see if it is now possible. I'd still get one to have in your parts kit, it might not fit on this bike, but it is a nice throttle.

I've had no trouble with the two Magura's I have used, but I do keep them out of the rain.

The pot in the Domino is rated IP67 so it might be more reliable. I'm running one of each now, the difference is immediately noticeable when bare handed, but I won't ride that way, with gloves the differences are less noticeable. The grippier Domino is slightly easier to keep where you want it, and the reduced throw is nice for the wrist.

Perhaps some grease or O rings on the Magura would improve it, the only major complaint I've heard is weather getting in the pot.
 
No - this puppy is a done deal - it's a smooth running well behaved 2WD and I can't honestly justify the cost of two Phaserunners for a bike that has no issues. It's quiet enough that peds don't notice anything when I pass - most don't think it's powered. It has no control or contention issues so - "if it works, don't fix it". :D

The Phaserunner heatsink thing just came up in a 'catch-up' conversation after J got back from his trip to EU - part of which was to Unicon. If you haven't seen it - check out his power unicycle video here - The drive system got machined/fabbed and the custom CA driving a Phaserunner programmed in the week before he left. Quite a fun project.

I will be putting a Phaserunner on my Paratrooper to get it fleshed out with more or less stock Grin drive, controller, and accessories for CA testing. The Mundo can't easily test some CA features or even allow standard CA accessories to be plugged in because of all the custom wiring and purpose-built controller mounts, etc. So - Mundo = around town grocery getter, Paratrooper = folder for car trips to far away trails + CA testing.
 
Nice, well I never consider my builds completely "done" but it is difficult to tear up something that is working. I was driven to the FOC controller on the Borg by failures, otherwise I probably would not have done so, but it is such an improvement that with that experience I am more willing to retire the working trap controllers. It is all an experiment anyway, learning something is worth a few dollars. Better throttle control, increased efficiency, much smaller controllers, more adjustments like flux weakening and variable regen/braking (on the DD motor wheel at least). It will also allow mixing the two motor types seamlessly with the torque request being the common control, and allow scaling front/rear torque easily. Hopefully it will be worthwhile!

Yesterday I rode the Bonanza with CA current control, and today I rode the Borg with true torque control. They are both nice, but the Borg is smoother on the low end, and more powerful on the high end. Hopefully the dual PhaseRunners will be similar, but with a bike that weighs half as much. :)
 
teklektik said:
No - this puppy is a done deal - it's a smooth running well behaved 2WD and I can't honestly justify the cost of two Phaserunners for a bike that has no issues. It's quiet enough that peds don't notice anything when I pass - most don't think it's powered. It has no control or contention issues so - "if it works, don't fix it". :D

...

A few thoughts on PhaseRunners. The PhaseRunner is superior at regulating peak motor currents compared to the conventional trap controllers. They actually allow huge peak motor currents at low speed which causes a lot of the damage and wear to geared motors (I see a lot of well documented maintenance in this thread). I suspect the PhaseRunner will facilitate much lower maintenance for geared hubmotors. In my testing I haven't heard any slamming of the clutches for example. In the DD on-road testing it feels very soft and silky, with none of the big jerky acceleration peaks that represent significant overcurrent events. Using a trap controller is like hitting the motor with a hammer fairly often.

To verify this would require measuring actual motor currents which would be interesting and not too hard to do.

Another benefit of real torque control is cancelling the drag of a DD motor when pedaling. It takes very little power and is easy to do when the throttle signal just needs to be set to a minimum very slightly above zero to make a DD motor have zero drag.

The size of these PhaseRunners is also significantly less than the trap units, making them easier to fit and leaving more room for other things.
 
I'm late to the party, I know, but wow, this build is just awesome. And every aspect of it is so polished... And it is very well documented !
Not the kind of resource seen everyday ! Thank you for that (and also for the tutorial about adding "turn signals" to an ebike, I'm adapting it for my needs)
 
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