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  1. #301
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    Modding your Yuba Mundo for speed in the city (part two)

    Hi,
    part two of what I did as an amateur. I am just sharing what I did and the following might not be for everyone plus it is dangerous to do unless you are confident and proficient.

    Replacing bearings


    I park my Yuba outside and also drive in the winter. With the weight plus the wheel protectors on them the rear wheel brearings can get dirty or dry.
    You can get new wheels if money is not an issue or you can take the wheel to a shop for new bearings but I decided to do it myself.

    • When to change bearings?


    Turn your bike around or lift the rear wheel. One indication is if there is play: can you easily pull the rims to and fro even though the bolts on the axle are tightened? Another indication is scraping noise when the wheel is turning. For this slowly spin the wheel with the pedal and listen. Just spinning it by hand may cause you to mistake scraping of the plastic cover behind the freewheel to the spokes with the noise from bearings.

    • Supplies

    I bought mine here. They are cheap and work for me. You are welcome to spend more but the branded will most likely use this bearing plus a brand on it
    https://www.jsbgreatbearings.com/bicycle-bearings-c-96/
    This is for stock wheel. You can double-check on your bearings. The numbers are on them.
    Front: 6001-2RS
    Rear: 6902-2RS

    • How to do it

    To get you started watch some videos,e.g. this one https://www.youtube.com/watch?v=ZhuAQqPXAQ4

    - Remove the rear wheel and the freewheel (with Park Tool FR-1 and chain whip)
    - Remove all the bolts, spacers and washers keeping note of the order. Clean those parts and lightly oil/grease them to prevent rust.
    - Now take a wooden hammer or use a light touch and hit the axle from the DRIVE-SIDE. You want to hit the axle out of the wheel like this

    HAMMER=> <----DrivesideAxle-Wheel-Non-drivesideAxle--->

    This will hit the axle out and will take one bearing with it. TAKE NOTE on which way the axle was in the wheel as you have to insert it correctly later.

    - look into the "axle-hole" in the middle of the wheel. I hope it is nice and shiny. If not you may want to get a new wheel as this is an indication that even with bearings this is not tight. Wheels are not that expensive on the Yuba page.
    - look into the whole at the center of the wheel from the NON-drive side. You can see the other bearing as its inner diameter is smaller than the diameter of the "axle hole". Lay the wheel onto the DRIVE-side on a soft surface or some wood.
    Now take the axle (or any other metal rod) and start tapping the bearing out from the inside. Gently hit it at 00, 900, 1800, 2700, etc until the bearing falls out. Be gentle but determined. Don't worry about damaging the bearing but you want to get it out in one piece. To explain another way: the bearing is like a thick ring stuck inside a pipe and you want to get it out of the pipe - o.k. not sure if that is clearer now. Ask me if not clear.
    - Wipe everything clean then grease or oil lightly where the bearings sit.
    - install the new bearing. You can't push it in by hand. Don't even try as you will hurt your finger or damage the bearing. Also don't hit it in with a hammer unless you have very good control of the hammer but even then you won't get it fully seated that way. You can get bearing installation tools ($$$) or go to the LBS and ask them to do it. Instead I just used the parts in front of me. This is how I did it.
    i) get two wrenches big enough for the axle-bolts.
    ii) insert the axle into the whole. just the axle but make sure it is the right war round. The drive-side is the one where there are more threads.
    iii) put the new bearings onto both sides of the axle.
    iv) put the old bearings on top of the new bearings. This is so that you push in the bearings by pressing as much as possible on the outer race of the bearing (the outer rather than the inner ring of the bearing).
    v) put the washers and bolts onto both sides. Hand tighten making sure that the new bearings sits evenly on the whole where they need to go in AND the old bearing sits perfectly on the old bearing. This is the order on the axle

    bolt-washer-oldbearing-newbearing-WHEEL-newbearing-oldbearing-washer-bolt

    Now tighten both bolts at the same time and watch the magic unfold in front of you as you smoothly push the new bearings in. Make sure the old bearings sit perfectly on top of the old bearings (see above).
    vi) You will notice when the bearings are all the way in. Then turn just a little more but do not force it as otherwise you will damage the bearing.

    Now remove the bolts and the old bearings.
    Install all the washers, spacers, and the freewheel back on the axle.
    Install the wheel back onto your Yuba.

    I think it is totally worth it especially after a long and dirty winter. Plus you will feel cool about being able to do it.
    Now hit me with your comments, reactions and questions!

    Ride in peace!

    Gauguin
    Last edited by gauguin; 05-15-2015 at 01:00 PM.

  2. #302
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    On a tangent, a quick look shows that the Yuba Mundo is one of the only, if not the only, cargo bikes that can use v-brakes instead of disks on the rear. I have a Heinzmann electric hub with no rotor mounts that a 20" rim built onto it. I can rebuild the wheel into 700c, but I like the idea of 20" in the rear for strength. There are a few manufacturers that make cargo bikes with 20" rear wheels, but all I have found use a disk brake.

    Is there such a thing as a Yuba Mundo with a 20" rear wheel? Or, any other cargo bike with a 20" rear that can use v-brakes?

  3. #303
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    Quote Originally Posted by honkinunit View Post
    On a tangent, a quick look shows that the Yuba Mundo is one of the only, if not the only, cargo bikes that can use v-brakes instead of disks on the rear. I have a Heinzmann electric hub with no rotor mounts that a 20" rim built onto it. I can rebuild the wheel into 700c, but I like the idea of 20" in the rear for strength. There are a few manufacturers that make cargo bikes with 20" rear wheels, but all I have found use a disk brake.

    Is there such a thing as a Yuba Mundo with a 20" rear wheel? Or, any other cargo bike with a 20" rear that can use v-brakes?
    Not an answer to your question but according to Sheldon Brown and other pro cyclists the main breaking should be on the front. So the rear break need not be that strong but mainly functions as a back-up.

    Braking and Turning Your Bicycle
    https://www.youtube.com/watch?v=frIKK_XU-qE


  4. #304
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    gauguin - I agree with St. Sheldon on most things, but when that article was penned(? typed?), cargo bikes were not as prevalent as they are now. I would argue that on a cargo bike that is heavily loaded, especially with weight on the rear, braking force is probably more evenly distributed in terms of stopping power. There is still undoubtedly more braking force on the front wheel, but the rear clearly contributes significantly to braking force. I think if you want the best braking performance on a longtail cargo bike then you need to do whatever you can to increase the braking force to the rear and improve modulation in any way you can. The best way to do this is with either installing hydraulic disc brakes, or alternatively mechanical discs with rigid brake cable housing going to the rear brake. I run BB7s and my rear brake has a somewhat mushy feel to it because of the long cable run. One of my next upgrades will be a truly compressionless, armored type cable housing for the rear brake.

    honkinunit - there is in fact a Yuba with a 20" rear wheel. I just came out and is called the Yuba Spicy Curry and is sort of Yuba's answer to the Xtracycle Edgerunner, however unlike the Edgerunner the Spicy Curry is purpose built as an e-assist bike and has a bottom bracket that accommodates a mid drive motor.
    Spicy Curry | Cargo Bike, Cargo Bicycle, Electric Bike Cargo, Family Bike

    Mechandy - I know AUS dollars aren't the same as US dollars, but do you think you saved an appreciable amount of money by custom-building your mid drive motors using the scooter motors and gear reduction, versus buying a complete unit like the Bafang 8Fun mid drive or something similar by another company like Stokemonkey or EcoSpeed? I'm doing my research, and frankly the cost of setting up an electric motor is pretty daunting. Many of the options for mid-drive available here in the US are easily $2500 or more. There are certainly some much MUCH cheaper Asian mid-drive motors but I don't know just how much I'd trust one of those, especially the electronics like the throttle, speed/assist selector, brake lever cutoffs, etc. It comes back to that old adage you know - "you get what you pay for."

  5. #305
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    Is it really worth upgrading the rear wheel brake?

    Quote Originally Posted by Velo Celt View Post
    gauguin - I agree with St. Sheldon on most things, but when that article was penned(? typed?), cargo bikes were not as prevalent as they are now. I would argue that on a cargo bike that is heavily loaded, especially with weight on the rear, braking force is probably more evenly distributed in terms of stopping power. There is still undoubtedly more braking force on the front wheel, but the rear clearly contributes significantly to braking force. I think if you want the best braking performance on a longtail cargo bike then you need to do whatever you can to increase the braking force to the rear and improve modulation in any way you can. The best way to do this is with either installing hydraulic disc brakes, or alternatively mechanical discs with rigid brake cable housing going to the rear brake. I run BB7s and my rear brake has a somewhat mushy feel to it because of the long cable run. One of my next upgrades will be a truly compressionless, armored type cable housing for the rear brake.
    Hey Velo Celt,

    I think hydraulic breaks are sweet and great to have and in the future we should all have them but by the sheer physics of bike-braking (I would be glad to have some nerd correcting me on this one) I question what difference they will make on the rear wheel even with the added weight as this is not a trailer but just your bikes "behind". Yes, better breaks with better modulation will help no question but here is my situation and I would value your input.
    I still have the original Promax TX-125 V breaks on front and rear. Recently I upgraded the cable and housing. Nothing fancy, just went to the LBS and got the supplies I needed from the helpful guys there and also got some new breakpads for $10 a month ago. Even with these brakes I can lock/modulate the rear wheel. I tried it last night again making some emergency test breaks. I also had a recent close encounter on the trail (asphalt surface) were a runner with headphones decided to suddenly cross in front of me. I was going at 30km/h (19mph) and I slammed the breaks and locked/modulated the rear break no problem.
    Nevertheless I am now upgrading the front to BB7 - that is a no-brainer to me now - but for the rear I am not sure it is worth it. How much more breaking power can I get given that I can lock/modulate the rear wheel already? (By "lock/modulate" I mean that I can break to lock and easily let go a little to keep it just below locking.) Is it worth the $100-200 (depending on set-up) plus the fun of installation and maintenance on the rear wheel?

    Thank you for your input.

  6. #306
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    Hi Velo Celt, great questions! To me, it all comes down to 'application'. What do you want to do and where. Our 5,000 km tour over 10 months, was only one tour out of the 54,000 km's we've toured over the last 6 years. Our experiences have taught us much over that time. The planning for this last tour took well over 9 months, and everything worked perfectly, apart from the rear rim failures. As you can see from my previous posts re the Yuba's, every detail had to be taken into account. The main reason for this, is that here in Australia, it is not unusual to find oneself in very remote country, where food and water, let alone bicycle spare parts, are impossible to find. We have cycled our way through areas where food and water is not available for 400 plus kilometers, so the engineering of the bikes, has to be right. This is why I designed the system myself. Everything, right down to the wiring, which can lose its ability to move amperage current under extreme heat conditions, had to be calculated and sourced. Each bike, complete with Solar panels, LiFePo4 batteries, charge controller, Rohloff Hub, and various other upgrades cost just over AUS$7,000. Thats excluding the cost of the Yuba's. The system I designed also enabled us to recharge mobile phones, computers and complete the 5,000 km's entirely off the sun, we did not have any recharge capability from mains power outlets.

    Luckily, the rim failures occurred in a place where we could easily get replacements, we learnt a lot from that experience. I have built many of these mid drive systems for customers over the past 8 years, and therefore have come to trust the motors I use and the system I designed, not only through our own touring, but also from the reliability my customers have gained. That said! If your application is not as demanding as the one I've outlined above, there are many other options available. BUT, I agree with you wholeheartedly, steer clear of the cheap Asian options!

  7. #307
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    Quote Originally Posted by mechandy View Post
    (...) We have cycled our way through areas where food and water is not available for 400 plus kilometers, so the engineering of the bikes, has to be right.
    Wow, that sounds so awesome. It must be such a mixed-emotion feeling of empowerment but also of trepidation to be out there and taking on so much responsibility for yourself and others.

    Quote Originally Posted by mechandy View Post
    BUT, I agree with you wholeheartedly, steer clear of the cheap Asian options!
    Here in Philadelphia we see many of those cheap systems being used by the Asian food delivery guys. Clearly for them the risk of failure is not a big problem as they are never far from their home-base so the cost-advantage dominates. Plus it's great to see them being used more and more around here. This was only made possible quite recently due to a change in city street regulations permitting stronger E-bike systems.

  8. #308
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    My big bike of fun

    The Yuba Mundo Thread-mrt7341jm67z49p50jlpw1ah08313xac.jpg

  9. #309
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    Modding your Yuba Mundo for speed in the city (part three)

    Hi,

    I am back for some more from me to share with you on what I did to my Yuba Mundo bike given I wanted to ride fast and safe in the city.

    Chain lubrication

    I often ride with trousers as I am commuting and getting them dirty from the chain is always a burden. So I went out to look for a solution (other than changing the chain monthly) on how to lube the chain to minimize dirt and friction without breaking the bank. Is that even possible? It turns out it is. The solution is to coat your chain with paraffin wax. Yes, good old candle wax.

    Someone actually did a very sophisticated test on it with reports on Bikeradar. In terms of friction it is the best out there.
    Friction Facts publishes UltraFast chain lube formula - BikeRadar USA
    Here are some handy instructions on how to do it:
    Lubricating a Bicycle Chain using Paraffin

    Make sure to first thoroughly clean, degrease and dry your chain. I coat my chain in a double boiler: big can with paraffin in it standing in hot water. Wait for it to melt then submerge the chain and wait a few minutes. Note: do NOT boil wax directly in a pot. Always use a double boiler. All you want is the wax to become liquid. Be safe: there is a risk of spontaneous combustion when you boil wax.

    If you can't find pure paraffin at your local store you can buy some very big candles at your department store but make sure to peel off the hard outer wax coating if there is any and remove the string by pulling it out from the bottom with some pliers.

    Once your chain is coated with wax, take it out with a tool and lay it on paper towels to cool. It should not be that hot but better be safe. The chain might be a little hard and inflexible at first but that is just the excess wax which will peel of quickly on the bike. If not then you did not clean the chain well at first (see above).

    This works best on a new chain.

    You may need to recoat your chain every month or two depending on how much you ride but it is worth it. Clean trousers and legs plus low friction at a very low price.

    Questions, comments, and reactions welcome!

  10. #310
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    Hi gauguin, yep, it's a great feeling being in the middle of nowhere and making it through, after several days riding, to somewhere......

    My comment re the cheap Asian systems is related to the fact that I have to repair them in my workshop. There are now literally hundreds of cheap brushless hub motors available, and when they are pulled apart, it is not hard to see why they fail. Coils are poorly wound, Hall Effect Sensors are badly positioned and easily get chewed off and there is often little consistency in the colour coding of the wiring for the motor phasing. I totally agree that it is great to see the uptake of electric bikes, especially for hauling cargo, but in our 'throwaway' society, where it's easy and cheap to go buy a replacement if something goes wrong, rather than paying for quality that lasts, to me at least, this is wasteful. I cannot repair badly wound coils that 'short', (because it's uneconomical to attempt to) and so I often have to send these cheap motors to metal recycling, in most cases, in less than a year after someone has bought one......

    I'm very interested to hear more about the changes in the city street reg's for electric bikes in Philly. We have a legal limit of 200 watts (250 watts if it incorporates a Pedelec system) here in Australia, which is pretty low. We run 350 watt motors on our rigs (yes, we break the law!) but we are quite prepared to stand up in Court and argue our case, if it comes to that. I've heard that Stateside, motor size reg's are far more liberal, is this correct, or does it change from one place to another?

    Cheers
    Andy

  11. #311
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    Would there be difference if that same situation of the runner cutting you off happened on a downhill and the mundo was loaded on the back and heavy? I cant quantify, but would guess a disc on the rear would help more in that situation. Who here can enlighten us on this?

  12. #312
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    Quote Originally Posted by mechandy View Post
    I'm very interested to hear more about the changes in the city street reg's for electric bikes in Philly. We have a legal limit of 200 watts (250 watts if it incorporates a Pedelec system) here in Australia, which is pretty low. We run 350 watt motors on our rigs (yes, we break the law!) but we are quite prepared to stand up in Court and argue our case, if it comes to that. I've heard that Stateside, motor size reg's are far more liberal, is this correct, or does it change from one place to another?
    Legislation varies by state and sometimes within state.
    Electric bicycle laws - Wikipedia, the free encyclopedia

    As for Pennsylvania, up until recently there was ambiguity in that E-cyclists at times received citations by the police as they thought E-bikes needed to be registered and ensured like motorcycles.
    Proposed Pennsylvania law would allow electric bikes without insurance, registration | Pittsburgh Post-Gazette
    The law now is here
    Electric bicycle laws - Wikipedia, the free encyclopedia
    As you can see we are permitted to use up to 750W (!) with top speeds of 20mph.

    If you can spare a moment it would be valuable for the community to read how you think one should convert a bike to an E-bike. Perhaps you wrote about it elsewhere in which case posting links would be great.

    Gauguin

  13. #313
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    Mechandy - I'd also like to know more specifics about the brand of motor you selected, batteries, controller, etc. I'm still quite a ways off from my own e-assist system but I'd like to know more about what you did in case it ends up being a viable option for me, maybe keeping costs lower versus buying a complete mid-drive system from someone else. Is your system designed to be pedal assist, as in you can pedal at the same time the motor is running or is it a system where you don't pedal while the motor is running? I've read about both types and think I'd rather have pedal-assist. Also, almost any touring I do would allow for plugging in to recharge at mains, but I'd also like to figure in maybe using a solar panel to try to recharge batteries while I'm out on the road. Currently I have a small external battery pack that can recharge itself via its own solar panel and it's adequate for recharging a cell phone a couple times at least. Also, I have a dynamo and front light setup that the light has a USB plug on it and will also recharge small electronics while the bike is rolling. I've looked at some portable solar panels that I could unfold and strap to the back of the Mundo which could help recharge a larger battery while riding as well.

  14. #314
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    Yuba in the city: shout or ring bell to get noticed?

    Time for a bit of fun laced with seriousness.

    What do you do to get noticed on the Yuba bike in the city? My approach is to assume that nobody saw me unless I established eye contact and also to be more understanding of the challenges of car drivers and pedestrians - after all they need to drink a latte, check their Facebook updates, AND navigate traffic. Being zen like that keeps me safe and calm.
    Yet at times I need to alert people of my existence. Cursing makes me angry so I avoid it as much as possible. Instead I often scream "wait!" which works better than "hey" or "bike".
    Ringing the bell does little until I installed a dingdong bell like this pretty one
    Kids Jumbo Bike Bell : Target

    or use two bells at the same time. I think the unusual sound gets more attention.

    What works for you? Please share ...
    Last edited by gauguin; 05-19-2015 at 07:34 AM.

  15. #315
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    Quote Originally Posted by gauguin View Post
    Hi,


    Make sure to first thoroughly clean, degrease and dry your chain. I coat my chain in a double boiler: big can with paraffin in it standing in hot water. Wait for it to melt then submerge the chain and wait a few minutes. Note: do NOT boil wax directly in a pot. Always use a double boiler. All you want is the wax to become liquid. Be safe: there is a risk of spontaneous combustion when you boil wax.

    If you can't find pure paraffin at your local store you can buy some very big candles at your department store but make sure to peel off the hard outer wax coating if there is any and remove the string by pulling it out from the bottom with some pliers.

    Once your chain is coated with wax, take it out with a tool and lay it on paper towels to cool. It should not be that hot but better be safe. The chain might be a little hard and inflexible at first but that is just the excess wax which will peel of quickly on the bike. If not then you did not clean the chain well at first (see above).
    I've been dipping my chains in hot wax for 2 years now. First, they are very rust prone, as wax turns out to be an exceptional degreaser. Second, it works fine on used chains and really gets them clean.

    I use a cheap plastic crockpot from a thrift store as a double boiler. I reuse the same wax over and over again, and i drop all my chains in every couple of weeks or so. On a mountain bike, which is where i use wax the most frequently, I find that in dry riding, the wax works well for ~50 miles and in wet muddy weather, it will not last long, but even when caked in mud for 20 miles, your drivetrain is much much smoother than any alternative. Every 12 to 18 months, I buy a new middle ring (maybe others too) 4 new chains, and a new cassette. Then I rotate the chains every ride or 2 and after a couple of weeks, all the chains go in the wax.

    All the dirt falls to the bottom of the hot wax, so you can let it solidify, and scrape the dirt off the bottom. You also don't want your chain to sit in the bottom with all the dirt, so I made a little cradle from wire mesh to hold my chain above the bottom of the wax pot.

  16. #316
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    Hi PretendGentle,

    do you clean your chain before re-waxing? It sounds like you just pop it in the wax and let the dirt sink to the bottom.

  17. #317
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    I'm looking at a mundo 4.3 frame build. I have no fat tire experience but would be using the bike mostly for running errands with kids or wife running errands since she cant fit on my surly karate monkey..... that I have kid racks on front and back.... and a bob.
    We live were it's paved flat bike path for three miles then a very friendly bike town.
    We will use it on bike camping trips/ dirt road easy trails
    I will electrify the front with a 48 V hub when the budget allows it, or mid frame.
    I know nothing of internal hubs but love the idea
    I can build the wheels... my DT swiss wheels on my KM are 12 years old and still run great.
    It will be used instead of driving
    I love you can tow the kids bikes along if needed.
    I like mechanical disc's
    I've been told by my neighbor his mundo did much better with a DH headset... his goes 30 MPH... mine wont! At least not right away, and I will set it up to run at 20 MPH Max with assisted pedaling
    any tips APPRECIATED !

  18. #318
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    Sorry
    Last edited by beoutside; 05-20-2015 at 10:03 AM. Reason: REPEATED BY MISTAKE

  19. #319
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    Quote Originally Posted by beoutside View Post
    I've been told by my neighbor his mundo did much better with a DH headset... his goes 30 MPH... mine wont! At least not right away, and I will set it up to run at 20 MPH Max with assisted pedaling
    any tips APPRECIATED !
    I don't quite understand: how can a different headset give you an additional 10 mph. Is it much lower for better aerodynamics?

  20. #320
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    Hi Gauguin and Velo Celt,

    Gauguin, many thanks for the feedback re the electric motor reg's in the States, 750 watt, wow....... I can only dream!

    Re some more info on the design and manufacture of my pedal assist system, I'd be more than happy to share that info with the community here. I haven't written about it elsewhere, mainly because our application is very unique and not what most people are looking for. I have sold less than 10 of these systems over the past 8 years and they have all been to customers looking to do the same as us, shift a lot of weight up some steep hills. Most people I come into contact with are interested in 'speed', the system I designed is not fast, it is built to extract the maximum amount of torque out of the motor at its peak RPM torque range. Over the 5,000 km's we travelled last year, our average speed was somewhere between 12 and 14 kms/hr, slow!

    At 130 kg's, our bike, cargo and solar trailers weigh the same as the lightest 250cc motorcycle available here in Australia. That motorcycle has a 32 Horsepower motor and our bikes have a 0.47 horsepower motor. We do a lot of pedalling! This is why torque and gearing become critical, especially when you are trying to get up 10 or 11% gradients. In planning our trip, we knew that we would have several of these kinds of gradients to climb. The other factor we had to consider, was whether there would be any flat ground for us to stop on these hills (to rest and let the motors cool down). A small amount of flat ground would enable us to easily start off again, without it, starting off on a 10% plus gradient, with this kind of weight, is damned near impossible. We had one hill, a 10%, 80 meter ascent over 800 meters with nowhere to stop, once we got on it we had no choice but to keep going. 800 meters doesn't sound like much, but at a speed of 4 km's per hour, pedalling hard and trying to keep the heavy load balanced (you can't peddle standing up), it feels like an eternity!

    Another hill we ascended had two sections, the first a 10% gradient over two kilometers, the second 11% over 3 km's, luckily the second section had several places for us to stop, with flat ground where we could start off again. You can see that flat ground in picture number 65 in the link below. It is a photo taken from the top of a safety ramp that trucks, going downhill, that lose their brakes, can use in an emergency. You can see the bikes at the bottom.

    On these kinds of hills, we are pulling close to 17 amps through the motors, which have a maximum current draw of 18.7 amps. This can only be done over short distances, otherwise the life of the motor will be severely reduced. The motor therefore has to be very good quality. Also, at 17 amps, we pass the peak torque / RPM range of the motor and when this happens, the motor torque starts to drop off rapidly,then you have to pedal much harder!

    The difficulty in designing any system like this, is getting the perfect or as close to perfect combination of gearing, torque, RPM, cadence, for the 'application' you have in mind. Understanding the formulae for moving a specific mass up a given gradient over a given distance is critical in the design process. Whilst it is possible to design a system that will do pretty much what you want it to do 80% or more of the time, as we found on the few hills outlined above, one quickly understands the limitations.......

    Vagabond Tour - 2014 - Kristin Rule

    Cheers
    Andy

  21. #321
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    Sorry multitasking at this end , his Ebike yuba mundo can do 30 and he wore out a xc headset two facts that may or may not be related

  22. #322
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    I just bought a mundo to build up and am looking for tips from people building them up to be used with a Ebike kit .

  23. #323
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    Quote Originally Posted by gauguin View Post
    Hi PretendGentle,

    do you clean your chain before re-waxing? It sounds like you just pop it in the wax and let the dirt sink to the bottom.
    exactly. At the end, I pour the wax and water from crockpot into a pan and put it between two pieces of wood to insulate it a bit. I figure the slower it cools the better, as most of the dirt and all the water sink to the bottom. I just scrape off and discard the dirty wax after it cools.The "clean" wax does turn a greyish brown over time, but I don't think it makes a big difference. My drivetrain is very smooth, even for all the wear it has.

    If I take someone else's supposedly "clean" chain (i.e., a chain with some wear that has been conventionally lubricated (wet/dry/drip-wax) and cleaned fairly thoroughly) and drop it in the wax, I can pretty much always see tons of black gunk flow out of it. My chains are never like that, even after dirty rides.

  24. #324
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    I just found a bionix set up laced in a rolling Daryl wheel with a 350 w motor and xl lithium ion battery ... Thoughts ? We live in a flat bike path area and I would be carrying two kids and groceries mostly over 10 miles tops. Not sure if it with fit the 14 mm drop outs waiting to hear from seller.

  25. #325
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    Marc from yuba has some adapters but they will only work with the older hub motors .

  26. #326
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    Any tips on the best chain set up? I'm hoping to run 11/32 in the rear and 22/32/4? Up front with a bionix rear end

  27. #327
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    Mundo v5

    I called my local shop to have them order a Mundo v4 for me, then just saw this video and had to call them back. The v5...



    It has the features I wanted in the v4 (and more) and would have had to upgrade. Cromo frame that is 5 pounds lighter, 1-1/2" headtube, lock tabs, Yepp easy fit mounts, 10mm axle dropouts, hydraulic disc brakes, maybe a cassette instead of a freewheel, and Shimano components.

  28. #328
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    Yeah, I was a little aggravated that the new lighter Mundo came out a mere four months or so after I built my hi-ten steel v4.3 Mundo. The only thing I don't like is the paint. I'd prefer the option for a satin black like my current Mundo, as I've never been fond of bright showy colors for frames. Visibility is kind of a "meh" argument, especially in the daytime. Reflective surfaces, both in the daytime and at night make a lot more different I think than frame color. The shop where I bought my v4.3 frame wasn't even aware that the v5 was coming out, and thus had no idea what the price was going to be. I think my two biggest grips about the v4.3 frame was that they cut the steerer tube for their style of stem (wasn't enough height for me, as I had to install an extender), and the paint is really crappy and thin. They really should've powdercoated the frames. I use Ortlieb panniers and where they attach and rub against the frame, the paint has already come off. I'm going to have to repaint those bare frame paint rubbed areas then cover them with a heavy duty frame saver tape.

  29. #329
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    Mechandy - I was trying to revisit your information about how you built your motor setups and can't seem to find any decent photos of the finished product. I wanted to see if I could find a good photo that shows most of how you set your rig up so that I could just save it to one of my files on mid-drive motor setups and design. I've been looking at a lot of commercially available stuff and am still not sure I like what I'm seeing. It looks like lots of mid-drive kits eliminate the ability to keep a triple or even double chain ring setup. I've been considering removing my largest chainring as I pretty much never use it but would like to retain my 38/28 chainring setup. Also, I like how your motor was mounted behind the seat tube and above the bottom bracket unlike most mid drives the Bafang which place the motor in front of and below the bottom bracket. I want to maintain as much ground clearance as I can, for future off-road adventures, so getting the motor into that dead area above and behind the BB seems like the best option. So, anywhere that I can find a link to good pics of your motor setups? Thanks.

  30. #330
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    Another question for Mechandy - since you installed Rohloff hubs, you only have a single front chainring, correct? Would a system such as yours still work with a double front chainring and an 8/9/10 rear cassette, or is the design of the motor and gearing reduction based on using only a 1x drivetrain setup?

  31. #331
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    I'm thinking about improving front light on my Yuba. Now I only have battery light. Bad thing is that its batteries have to be charged every day or two. That is sometimes really annoying. Also for bike touring for few days or even weeks accu light is not the best.

    So I would like to improve my front wheel with a new dynamo hub. I have disc brakes and I also want to have the sturdy wheel as I have now (heavier spokes).

    Can you recommend me some disc brakes ready dynamo hub suitable for Yuba Mundo? Can be there some problems?

  32. #332
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    You could try sending Yuba an email to see if they will sell the wheel that comes on the new V5 Mundo. I've only had mine for a week, but it's been great so far. It powers front and rear LED lights.

  33. #333
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    A few shots of my V5

    The Yuba Mundo Thread-mundo_2015-08-27_firstride_02.jpg

    The Yuba Mundo Thread-mundo_2015-08-30_02.jpg

    The Yuba Mundo Thread-mundo_2015-08-29_02.jpg

  34. #334
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    I have emailed Yuba about recommended hub dynamo right with the answer in this forum. I'm waiting for an answer. But it's a good point with the new wheel from v5, I will surely ask.

    Did you tested the front light on the new Mundo in the night? Is it sufficient?

    BTW, I am not seeing the pictures in your second post. (I'm getting message: Invalid Attachment specified. If you followed a valid link, please notify the administrator)

  35. #335
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    Has anyone modified a Hooptie to work with a V3?

  36. #336
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    Quote Originally Posted by lewke View Post
    Has anyone modified a Hooptie to work with a V3?
    Since no one replied and Yuba confirmed the Hooptie was a almost 2 inches too short I decided to just make one from PVC....also added foot pegs via old handle bars and hose clamps......The Yuba Mundo Thread-image1.jpg

  37. #337
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    Yuba Mundo v5 in Green

    I've been riding the Green Mundo v5 for about a month + now. My 4 year old and I love it. The tow tray has allowed my little kid to go for longer bike rides now knowing that he and his bike can get a ride/tow back home. Our recent ride to the skate park was a blast. Carving the bowls on the Mundo is like a massive long board on two wheels :-) The Mundo has been to the grocery store, errand runs, work commutes, snow rides, and country gravel road rides. Can't wait for the summer to try a short camping trip with the family. I really enjoy the front basket as it allows quick access to items instead of getting off the bike and rummaging through the panniers. I made a few modifications. At first I used some pedal power straps I had in the garage. Now I'm using my spd pedals. Also swapped out the seatpost for a black one I had purely for aesthetics. I also put on a narrower saddle. Lastly, I took out the rail on the monkey bar closest to the saddle as it was hitting the back of my thighs. Monkey bars still work and glad I got them as my wild child likes to surf and spin around backwards to wave at traffic from behind. Fun and functional ride! I've attached some pics ...
    Attached Thumbnails Attached Thumbnails The Yuba Mundo Thread-photo-2-1-.jpg  

    The Yuba Mundo Thread-photo-2.jpg  

    The Yuba Mundo Thread-photo-1-.jpg  


  38. #338
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    Hello,

    I am very seriously considering the purchase of a Yuba Mundo with the NuVinci Hub.

    I have ridden a Novara Gotham with the NuVinci and it seemed, with the 700c wheels, NOT to have very good low "gearing".

    I'm wondering, with the 26" wheels will the Nuvinci be alot-better on the "hill Climbing" setting?

    Thanks, Paul

  39. #339
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    Quote Originally Posted by pwhallon View Post
    Hello,

    I am very seriously considering the purchase of a Yuba Mundo with the NuVinci Hub.

    I have ridden a Novara Gotham with the NuVinci and it seemed, with the 700c wheels, NOT to have very good low "gearing".

    I'm wondering, with the 26" wheels will the Nuvinci be alot-better on the "hill Climbing" setting?

    Thanks, Paul
    You can always fine tune the Nuvinci hub to your liking with different cogs and/or chainring sizes. Check out this Nuvinci conversion thread on mtbr ...

    NuVinci n360 conversion

    There's a nice Nuvinci spreadsheet someone created on this thread comparing 700c to 26", cog/chainring sets, gear ratio, etc ...

    Hope this helps and have fun building up your bike!

  40. #340
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    monkey bars

    Nice roll bars ! I use the yuba monkey bars but need to modify them so they do not hit the saddle . I do like the fact I can remove them in teo minutes for adult riders headed to town!
    Name:  avitarsize.jpg
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    Quote Originally Posted by lewke View Post
    Since no one replied and Yuba confirmed the Hooptie was a almost 2 inches too short I decided to just make one from PVC....also added foot pegs via old handle bars and hose clamps......Click image for larger version. 

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  41. #341
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    pics electric assist yuba mundo

    Also someone posted the bontrager cargo bags on close out for 60 bucks each, I can't find any reviews but for 120.00 for a pair ..... going for it !

    The Yuba Mundo Thread-photo.jpgSweet I did a similar build in orange but added an BMC electric assist rear hub
    Last edited by beoutside; 05-02-2016 at 09:55 AM. Reason: pics

  42. #342
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    Getting the bugs out of my electric asist cargo build

    Still working on a aluminum battery box but its getting there! Thinking of getting a set of bontrager cargo bags since they are on close outs.
    Donny

    Anyone tried the bontrager cargo bags, you can get a set shipped for 120 right now . The Yuba Mundo Thread-photo.jpgThe Yuba Mundo Thread-photo3.jpgThe Yuba Mundo Thread-photo2.jpg

  43. #343
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    My brother's new Mundo. He carts his 2 kids all over NYC.
    Attached Thumbnails Attached Thumbnails The Yuba Mundo Thread-yuba.jpg  

    2012 Specialized Camber Comp 29er
    Trek 9800 OLCV, XT upgrade 26er
    KHS Fleetwood
    Schwinn 20" Fastback 5 speed stick shift

  44. #344
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    Quote Originally Posted by gauguin View Post
    Not an answer to your question but according to Sheldon Brown and other pro cyclists the main breaking should be on the front. So the rear break need not be that strong but mainly functions as a back-up.

    Braking and Turning Your Bicycle
    https://www.youtube.com/watch?v=frIKK_XU-qE

    I'm a bit late to the party on this, but you might want to read what Sheldon said about braking on tandems, which have a lot in common with cargo bikes. The TLDR version is that rear braking is much more useful and important on these bikes.

    Point 1:
    With both a tandem and a loaded cargo bike, there is enough weight at the back, and the CG is low enough, that it is possible and even likely that you can skid the front wheel before the back wheel lifts. This is essentially impossible on most solo/non-cargo bikes. (on dry pavement anyway) That means that for minimum stopping distance, the rear brake on a tandem/CB must contribute, and it is safer to rely on it quite a bit, because it is rare to skid the front wheel without crashing. If you are skidding the rear wheel, you are using too much rear brake, if not, you could maybe use a bit more and stop quicker.

    Point 2:
    Both tandems and cargo bikes can be quite heavy for the amount of aerodynamic drag they suffer. This means they can build tremendous speed when coasting downhill, and braking will frequently be required to keep speed within safe/comfortable limits. The weight means that the brake(s) will be creating gobs of heat. Tandems are frequently equipped with special drag brakes for this purpose, but I have never seen such on a cargo bike. As an alternative, the cargo bike rider can use the rear brake to control speed on descents, keeping the front brake in reserve as needed for actual stopping duties. If a rear rim should overheat to the point of blowing the tire off, you are far more likely to be able to "ride it out" without crashing than if this happens on the front.

    Incidentally, the second point argues in favor of aerodynamically "dirty" cargo bikes, but that won't seem so nice in a headwind!

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