Several Yuba Mundo Builds

[Kiwi]

Here are some photos of the Yuba Mundo cargos I have built over the last few years.

2 72v15ah beasts at 40amps with disk brake upgrades crystalyte x5305 motors.






72v20ah 100km range, x5304 regen, disk, 52 tooth front chain ring, temp monitor...wahoooo, this bike is awesome.


48v10ah nine continent front


2 x 36v15ah 25amp controller nine continent front. Really nice set up. 36km/h cruise 40km range.





They make such great electric bikes. SO useful.
Really looking forward to getting some of the new frames.
I have designed the battery cases and torque arms specifically for the bike. Yell out if you want some.

[mastershake916]

I have always thought that they would be great e-bikes, but couldn't see a good way to use a hub motor on it because of the 14mm dropouts.
How did you do it?

[mabman]

Nicely done Kiwi.

[miuan]

I'm interested in the dropouts too. Do they still have the 1" threaded steerer?

[Kiwi]

There is a thread on it here. http://lh3.ggpht.com/_xtfwwaIXUcM/SrmQ6kx3EiI/AAAAAAAADH8/NZVl5ZvlC00/PICT0376.jpg

Basically the axel is 90deg to the flats, so the 14mm axel fills up the space. Then I use custom torque plates to transfer the load to the frame.
The picture show the first ones I made, but then I changed to longer arms, worked perfect.

The distance between flats should be 10.1 not 11 as shown in the drawing. Once zinc plated they are a snug fit.


Showing original reaction plate.


Showing new plate design (note should be 10.1 not 11.1 across flats.)
Sorry dont have picture of new plates they have gone with the bikes.
I can supply a DXF file for you to take to a laser cutter or CNC mill person, or can make and send you some reaction plates in the post.

I made custom ones for the front too. I will find some pics of them.

[mastershake916]

Nice solution. What's the range on those suckers? They look like serious moped killers.

[mr.electric]

Nice work. Very Clean.
The manufacturer of the bicycle -Yuba has released an electric bike
http://yubaride.com/electric-cargo-bicycle

[joe tomten]

Kiwi,

these are just great! I'm way envious.

I've been pondering the ammo box battery concept for an xtracycle build i have going - and this has me completely convinced.

Are you happy with the balance of things where they are? And why did you go to the trouble to stick batteries in the triangle if in fact you liked the rear balance.

the xtracycle will be less rigid than your bikes. the guy before me just put them in milk crates on top of the rear up behind the seat.

Joe

[Alan B]

These look really nice. Very clean. Great for carrying some cargo, or a really long range battery pac

How do these compare with the Surly Big Dummy? What would make one choose one vs the other??

[Kiwi]

Sorry, never experienced riding a big dummy so cant say.
With 2 big batteries on each side they are heavy bikes. With one battery in the frame its much better handling and you can get better use out of the carrier area. I am building one at the moment which will have the batteries under the running boards, so you wont see them and they will be down low. It will have a rear NC 8x8 or 9x7 @ 72v 30A.

[amberwolf]

If it helps you at all, in my various experiments with placement on CrazyBike2, the one that really improved handling the most was to put them in the frame as close to a line between the axles as possible, where they are now. It was actually a bit better when I had the powerchair motor mounted just below them, as that weight was below the axle where the batteries are mostly above.

When they're out to the side, then it doesn't seem to make too much difference whether they are above or below the axle line, as their outboard placement has more effect. I tried them in the cargo pods, forward and rearward, well-forward of the pods and as far inboard as they'd go under the seat along the lower pod rails, etc.

The closer they are to the center of CB2, the better, in every axis, so far.


BTW, when I have the cargo pods taken off, it rides even better.


Note that in the pic below, the seat is laid back because the front mount broke, but it's the only uncorrupted pic I found of a full side shot as it is right now:

[ecowheelz]

Great job on these bikes! Nice clean installs

[Kiwi]

kiwi-
Just saw your Yuba thread - very interesting - I am just starting a Yuba build. I'd like to leverage some of your efforts:
(1) what are we talking about to post a pair of torque arms to CT, USA and when might they ship? What material are you using (e.g. stainless?)
(2) what are the inside dimensions of your vee box and what are you asking?

I have a different custom Yuba torque arm design but it has no advantages over yours so the easy way is the best way...

I am building to a 48v30AH headway battery (same net capacity as your 72v20AH) and was planning on splitting it as panniers as you did, although forward a few more inches by extending/cantilevering the side-loader decks forward. I am curious about any comments you might have about the handling of your efforts... particularly if you have finished/tested the batteries-under-side-loader-deck bike. I was seriously looking at that strategy (stealthy) but it seemed that it required flattening the case (which moved weight rearward behind the rear axle) and did not actually improve the 'outrigger' weight placement (i.e. no closer to side-to-side bike centerline). Very curious how it worked out in real life. My bike is on order and so I don't have the advantage of simply *trying* different placements

Anyhow - definitely would like to hear back on the parts above.
Thanks!
-teklektik

Hi,

First, my Yuba frames are the older 2.0 frames. You will be getting a new model frame. I am not sure my torque arms will fit. If I had a frame I would design and produce the arms, but we here in New Zealand are struggling to get the new bikes.

Your battery pack is going to be really heavy. If you are going for a rear motor, you are going to bust spokes.
I had to relace my wheels with 10ga motor cycle spokes.

If you go front wheel motor, then no issues as not much weight on front wheel.

If you try to move the batterys forward on the side loaders you will break your leg. Allready had one rider with broke ankle. What happens is that you put your foot down and you get run over by the side loader. The side loader bars are on an angle at the front so your foot gets pushed out the side instead of breaking. THis is why I have gone away from the boxes on the side loaders to in the frame triangle.

You could split the pack up into 3 48v 10ah packs, one on each side loader (within the frame) and one in the frame triangle or on a front carrier.

If you have a rear motor and rear batteries, you will hardly be able to lift the back of the bike. You have to have the best tires and tubes you can get to avoid getting punctures. You will need disk brakes at both ends to slow you down and regen too will help.

Best option is to spread the load between both wheels as best you can.

[teklektik]

Thanks for the insights - especially regarding the angled design of the side loader bars - not obvious. I had already decided to move cells to the frame Vee for the reasons you pointed out and to take advantage of amberwolf's observations above. The rear spoke issues are interesting considering that even a heavy battery pack is far under the load rating for the bike or the load carrying a passenger back there. I have 12ga spokes - we'll see how they hold up.

I saw your frames were v2's but I thought you might be getting some newer ones PDQ (If you check the Yuba site, the eMundo page shows the new v4 frame). Sorry to hear about the bike availability issue down there. You are right - I will move on to a locally grown torque arm/axle adapter. Hope you can get some bikes down there soon

Anyhow - thanks for posting your stuff - nice to see such slick installations.

[boostjuice]

(If you check the Yuba site, the eMundo page shows the new v4 frame)

You mean V3 right? http://yubaride.com/mundo-cargo-bike

First, my Yuba frames are the older 2.0 frames. You will be getting a new model frame. I am not sure my torque arms will fit. If I had a frame I would design and produce the arms, but we here in New Zealand are struggling to get the new bikes.

Hi Kiwi. You might be aware of this already, but as I myself am looking at getting a V3 Mundo frameset i thought id post my findings. Although the Australian distributor is the closest to NZ and perhaps seemingly the obvious purchase point for NZers, it does seem Yuba USA will Airmail deliver (3-15 days) to all of Oceania. $70 for a complete mundo, and $45 for a frameset. Are you having troubles procuring one via this avenue? If so please tell of the difficulties?

[Kiwi]

I did not realise they would ship for that. Thanks.

Partner and I have been the Yuba NZ distributor for 3 years. Getting one bike easy, and I should do that, getting 30 bikes, harder, and there are a bunch of business challenges holding us up getting more bikes. The NZ ezee distributor will be bringing in the e-mundo, and I will hopefully sell them, though I like to do my own conversions for customers. Based on what I know about the ezee gear, the bike should be good, though 36v10ah is not enough battery for hauling loads around, especially in NZ where everywhere is a hill.

Yuba USA will Airmail deliver (3-15 days) to all of Oceania. $70 for a complete mundo, and $45 for a frameset.

Where did you find this info? I dont see it on the web site.

[teklektik]

You mean V3 right? http://yubaride.com/mundo-cargo-bike

The whole site isn't updated to reflect the revised v4 frame yet, just the newer eMundo shots. See: http://yubaride.com/yubashop/product.php?id_product=28. Visually, a few changes aft of the seat.

... The rear spoke issues are interesting considering that even a heavy battery pack is far under the load rating for the bike or the load carrying a passenger back there. ...

Re: spoke issues on rear drive Mundo: ahha - 48 spoke stock rear wheel vs 36 spoke w/hub motor.... looks like a bit of load capacity derating may be in play w/o special attention to the hub motor wheel build. Kiwi - thanks for the heads-up.

[Kiwi]

its a combination of weight loading and torque from the motor.

You need to use a super stiff rim, otherwise the rim becomes oval under load and the spokes loosen and tighten on each revolution. Does not take long for them to fatigue and break at the bend. If you are going for a rear motor, get a serious downhill rim, then you might be good with 12g spokes. If your batteries are up front, then I think you will be ok. We had 2 adults and 2 kids and broke 5 spokes on one trip running 12g, but average rim. After going to 10g no more spoke issues.

[teklektik]

Set up with Fat Franks on Sun Mammoths - triple-hollow I-beam construction, nickel-plated brass eyelets. Should be good except for bike-eating pot-holes....

[boostjuice]

I did not realise they would ship for that. Thanks.

Partner and I have been the Yuba NZ distributor for 3 years. Getting one bike easy, and I should do that, getting 30 bikes, harder, and there are a bunch of business challenges holding us up getting more bikes. The NZ ezee distributor will be bringing in the e-mundo, and I will hopefully sell them, though I like to do my own conversions for customers. Based on what I know about the ezee gear, the bike should be good, though 36v10ah is not enough battery for hauling loads around, especially in NZ where everywhere is a hill.

Yuba USA will Airmail deliver (3-15 days) to all of Oceania. $70 for a complete mundo, and $45 for a frameset.

Where did you find this info? I dont see it on the web site.

You have to go through the first processing steps of placing an order before you get the shipping quote. But never mind, it was a false alarm. The Yuba website is misleading due to a lack of updating their checkout process. I contacted Yuba to confirm what their automated checkout was telling me:

"Hi there,

I just used your online checkout to calculate the cost of shipping to Australia for a Yuba Mundo V3 frameset.

I was quoted the following:
Oceania ? ? ? ? 3-15 days ? ? ? $45.00 (tax incl.)

Is this shipping quote accurate?? It seems too cheap for such a large bulky item via airmail. Is the shipping service offered indeed airmail?"


...and got this response.

"Thank you for your email. Well spotted, actually the $45 in shipping was for shipping from Australia to Australia.
We don't take orders any more from the US to AUS or NZ since we have distributor down-under (FIY shipping is $650 bike from USA).
I will encourage you to contact Gary Cookson to discuss your needs."

So it looks like you've got the distributor exclusivity you need to survive in a globalised market - although horrendous airfreight costs for such large/heavy items kind of ensures that
Good luck with your business, they are sweet bikes, and i have no doubt you can fit waaaaaay better electric conversions than the elMundo offering.

[boostjuice]

You mean V3 right? http://yubaride.com/mundo-cargo-bike

The whole site isn't updated to reflect the revised v4 frame yet, just the newer eMundo shots. See: http://yubaride.com/yubashop/product.php?id_product=28. Visually, a few changes aft of the seat.

Indeed, it seems your right. Website needs updating.

"Well spotted. What you are looking at is the difference between the V3 and V4 frames. I found out last night that all of our bikes will be the V4 frames which is great because they shaved another 2.5kg off total weight. We should have updated specs and images on our site soon." Gary Cookson Cargocycles

V.4




V.3

[Kiwi]

Cool, thank goodness they got rid of that diagonal bar behind the seat post. That opens up a heap of opportunity for batteries and stoke monkey style installs.

[teklektik]

I'm not sure about the designations, but I believe we have images of four different frames.

(1) The dark blue bike (image 4 above) is the oldest. It has five luggage rack stays per side:
- The forward luggage rack stay (#1) is pinned to the outside of the seat stay and a strut continues the line from that point on the seat stay to the bottom bracket (pedal hub).
- The next luggage rack stays (#2 & #3) join and terminate on the chain stay.
- The last rack stays (#4 & #5) join and are pinned to the outside of the seat stay extension behind the rear axle.
- It has the blocky rear clamps for the side loader frame.

(2) The light blue frame above is the next version.
- Luggage rack stay #2 has been eliminated.
- Rack stay #3 is welded to the seat stay instead of pinned to the chain stay.
- Rack stay #5 is now welded to the seat stay instead of pinned.
- The rear side loader union is revised to eliminate the clamping block.

(3) The first two images above are the next version (fairly recent). Minor changes.
- The #1 luggage rack stay now terminates in the seat stay and no longer extends through to the bottom bracket (Stoke Monkey friendy).

(4) The current image of the eMundo http://yubaride.com/yubashop/product.php?id_product=28 is the newest incarnation.
- Another luggage rack stay has been removed (originally #4).
- Forward stay #1 has been relocated to the leading edge of the rack and now terminates in the seat tube instead of the seat stay.

I believe there was also some widening of the chain and seat stays in (2) and (4) which is not visible in the images.

I took (1), (2), (3), and (4) to be v2, v3, v3.3, and v4 respectively but I could be wrong about this.... Anyhow, it's interesting to see the evolution and simplification of the design.

[boostjuice]

How many revisions do they want to make! You'd be good at Wheres Wally judging by the detail you picked up in those photos. I just hope the load carrying capacity isn't compromised by the later revisions weight saving measures.

[Richard N]

Hello Kiwi

Those are some very nice clean looking builds you've put together there, I was hoping that you could tell us some more about the components you used, controller type, battery details, and so on. I'm looking at starting a Mundo project myself in the near future and would like to source out the best possible parts and plan as many of the details before hand as I can.

I'd also be very interested in hearing how your new build is coming along, how are the battery packs under the side load platforms working out?

Your experience with these bikes and converting them to electric would be very welcome information for me.

Thank you
Richard