Yuba Mundo fat tire electric

[Chalo]

There is just no way a front hub motor will spin with the weight distribution of a longtail. Move the rear wheel that far back, and the front wheel picks up much more of the rider's weight.

I say get the shortest fatbike fork you can find, to minimize the effect on handling from jacking the front end up. I'm guessing the Moonlander is not the shortest that takes a 135mm hub and a 4" tire.

 

[ridethelightning]

Yeah I gave it some thought. I cant afford lipo. And for $500 I could go agm 55ah and get way lighter batteries like 35 lbs each. But essentially I am paying $100 more for 1/2 the battery that I can get if I get a full size one...

Is it smart to go heavy probably not? but it will basically be a tank for my daily trips to the post office. That is what it would mainly be set up to do. I would need a big bank to get a heavy 150-300lb pay-load all the way there.

As far as brakes I would have probably a hydraulic disk brake on the new surly fork and the rear frame only has a spot for v brakes so....... hopefully stuff gets out of the way.

that 300lb payload wouldnt be a white powder by any chance would it? :lol: :lol: :lol:

 

[dogman dan]

I agree, front wheel spin will only happen if it's wet and muddy, and uphill. It could slip an inch getting going, but so what? Likely won't even do that.

A trailer will be the way to pack that lead. I never said a strong ebike can't move a lot of weight forward. I'm saying it will be wobbly and difficult to get going from a stop, and that steering inputs will transfer to whatever is weakest. 400 pounds in the back, it's going to flex the frame. Then you have to adjust to that, and think about it the whole ride. A stronger frame helps immensely with this, but a trailer, or a trike longtail would work best for that much lead.

Again, not spewing an untested opinion here, I ride a longtail with a big load.

I also hauled loads up to 500 pounds routinely, by hooking a trailer to a trike. REAL easy to hook up a trailer to a trike. Have you looked at all at the possibility of a trike with front drive, and a trailer. A very very simple hitch allowed me to hook 500 pound loads to a Schwinn trike, towing a garden wagon.

You'd want a better trailer, but you can hook one of those lawn tractor wagons to a trike so easy.

 

[mr.pibb]

Pibb where do you live ?
Get a real battery. Lead is dead. Lead ? Clue.

lead is definitely not dead yet, it still rules with the world's overall battery consumption, but obviously there are many advantages of going to lithium. I wanted to put some solar panels on the bike and since the charge rate is not consistent with solar you essentially need a lead acid battery. And I am fairly dead set on putting on some panels so I am stuck with lead until I find that there is a charge controller on the market that will not hurt lithium batteries.

But ok guys you talked me out of the 105ah 57 lb marine batteries. I agree it is just too much. I will either go with 35 ah or 55 ah. So that will drop the weight 60-120 lbs to something a little more reasonable.

 

[mr.pibb]

I think the trailer is the best way to go. I don't think it will take too much work to mount a hitch receiver to the Yuba for the yard trailer. The main problem I see is placing the height just right to work out the tongue weight. Thanks for the advice!

I agree the frame is going to flex, and spokes will break, and other damage. But if you watch the video I posted with the bananas: That guy had 400 lbs of weight and not very well placed. So the bicycle did walk all over the place. With the weight low and center and with a little reinforcement of the frame it will not bounce around anywhere near as much. But yes I already agree 228 lbs is way to much. I will either go with 35 or 55ah @ 48v which will bring the weight down to under 100 lbs if I go with the 35ah.

Oh and I do live in Miami Florida so even though there is plenty of powder flowing the streets, no that is not what I will be transporting. 8)
Believe it or not I will be carrying more lead. lol I sell lead fishing weights. So for any fisherman out there:
http://lead-bandit.com

 

[dogman dan]

Ha ha, no wonder you are a lead head. 25 ah might be enough to make it by lead. Assuming 15 mph or less travel with a really loaded trailer.

Don't overlook the possibilities of lead and lithium. 15 ah of lead, 10 ah of lithium? 48v 10ah of RC lico is about $300. Again, I'd far rather have that than the fat tires first. run regular balloon tires for now.

Changing the cargo load to towed, you will eliminate a lot of that wobbly bendy frame issues. But yeah, if you mount the lead on the bike, low on the sides is the place for it. My cargo bike handling improved a lot when I got the cargo carried low in some panniers. It still flexes when really loaded, but 25 mph is fine. That's with about 100 pounds on it. About what 25 ah lead will weigh.

So that's a doable deal now. 100 pounds of lead on the bike, tow up to 500 pounds on the trailer, if your motor can hack that.

What I was picturing is how it would handle with 300+ pounds on the rear end, much of it on the top deck. It's just so fun if you drop the bike loaded like that in an intersection or something like that. Move that extra cargo weight to a trailer and everything will be better.

I have wondered about the garden tractor trailers, then weld a special hitch to it to have an arm that attaches to the frame on both sides. Sort of like bob trailers.

I've also looked at welding a similar hitch to a dolly, making an instant two wheel bob trailer.

 

[mr.pibb]

dogman are you talking with experience from another mundo or a different long tail? Just curious...I looked at like the big dummy and extra-cycle and the mundo just seemed like the best option for me. It definitely appeared to be the strongest frame design. And I was going to buy whatever was within reach from cl anyway and it just so happened to be a $225 mundo.

Run lead and lipo.... hmm never really thought of that. 2 completely different systems or a mixed one? They would have to be separate run in parallel I imagine. Then I suppose I could still charge from the solar... But how would you isolate the lipo from the lead. Because if they aren't at the same voltage wouldn't they charge each other until the voltages equalized? Now you have me thinking hard. lol

 

[dogman dan]

The mundo may be much stronger than my frame. My longtail is homemade, and very stiff. But may have more frame flex than your mundo will.

Here is the thread on my longtail. I rode it 2000 miles this year, including some long tours loaded with camping gear.

http://endless-sphere.com/forums/viewtopic.php?f=6&t=28389&hilit=bouncing+betty

All the flex in this thing is from the seatpost forward, it's not a lot, but when it starts going into that slow wobble at 25 mph, that 100 pounds of cargo in the back starts to push you around a lot. Takes a lot of finesse on the handlebars to make it less rather than more getting worse. Rear brake helps damp it.

 

[dogman dan]

I also carried lots of weight on other short bikes, having the same issues with rear weight whipping the frame. One particularly soft frame did this carrying only 15 pounds.

For sure, a mundo will not have this problem as bad as a regular bike. But it still comes down to the quality of the tubes in the front triangle of the frame.

Start with 100 pounds carried low on the sides, then see how much more you can carry.

 

[mr.pibb]

Yeah I was able to find one of your threads on the homemade longtail. I wish I could navigate es better to find stuff like that. Theres so much cool stuff already done that I wish I could find easier. That thing is awesome! So what kind of top speed were you hitting with that 40a controller at 48v? That's basically what I am planning to run too. I only really want to get to 15-25mph loaded, but I imagine empty it should do well over 30mph.

Thanks dogman.

 

[dogman dan]

Fastest motor speed I was getting was about 33 mph, fresh battery. Generally 30 mph any time on a ride. 5304 crystalyte motor.

Once I had more than 100 pounds on it though, including the battery weight, it needed to be kept to about 25 mph. My full 45 ah battery weighs about 35 pounds, and has 35 ah of capacity left. That 35 ah will take me up to 80 miles, 60 easy, at 15 mph or so.

One thing I have noticed though, is under 15 mph gets hard to steer, awkward when fully loaded. It's much like an old heavy Honda street bike, touchy at 5 mph, fine faster when you get the gyroscopes spun up.

I found out the max speed for this bike the other day, when loaded with just the battery and another 15 pounds of gear. At 38mph it went into a wicked but slow tank slapper. That was descending a huge hill. So that's the absolute max for this bike. I'm sure it could take more if I added some bracing, like the bars you see on beach cruiser frames. Next time I build one of these, I'd love to do it with a cruiser frame, but finding one with 1 1/8 headset is hard, especially when your price range is 20 bucks.

I just replaced the motor with a slower one, so now my top speed is more like 26 mph. Now it really rides efficient at the speed I like best, about 18-20 mph.

 

[Drunkskunk]

Dogman, you ought to put a link to your Longtail build thread in your signature line. That bike is awesome and often used as an example, might as well make it easier to find.

 

[999zip999]

Sorry for the punch to the gut. As you live by lead. A speed of 22mph or less for range with that weigh. I know everyone throws out 40-45mph, but 20mph will get a lot more range.

 

[mr.pibb]

Sorry for the punch to the gut. As you live by lead. A speed of 22mph or less for range with that weigh. I know everyone throws out 40-45mph, but 20mph will get a lot more range.

NO worries lol :lol:

I really only want to go 20-22 anyway because I need to be a 'legal' build. FL dictates 20 mph but there is no watt or electric hp limit
And I will have a couple hundred lb payload not even counting the batteries or me just with my packages. So I do want to keep it under some control.
I will only have the one front brake until I figure out where to weld a caliper mount on the rear because it was set up for v brakes which I am told will not work with my new rims.

I have other faster set ups. This is not a speed machine. Even if I only got 15 mph all loaded down I would be happy. This will be my go to for groceries and stuff like that. Consider it more like the minivan of electrics. Basically I can sell my car is the idea and still carry anything that I needed to. I have a trailz and a modified a2b for commuting.

 

[dogman dan]

Not to forget, 15-18 mph will mean carrying less lead you are taking to sell at the moment.

 

[mr.pibb]

Well now I just have to get to work. I am waiting on the new fork to come in and the other fat tire parts. I still need to get a crystalyte hs3525 and 40a controller. Im thinking of just buying it new from http://www.ebikedeal.com/crystalyte.htm unless somebody had something they wanted to sell used. I would go that route too.

Hopefully I can get some pictures up soon and maybe a video under full load.

And yeah you should add that thread to your signature dogman. It is epic. Should be sticky'd

 

[ridethelightning]

what about leaving the led at home, to charge on solar, while you go cruising round light as a feather on lithium?

ofcourse this means 2 lots of batteries to buy.....

 

[mr.pibb]

Good idea, but its just not the same. I would love to have the whole house on solar. one day....

 

[mr.pibb]

Hey I could fit motorcycle rims... How large of spoke can I fit (with drilling if need be) on a ht3525 crystlyte?

 

[Chalo]

I will only have the one front brake until I figure out where to weld a caliper mount on the rear because it was set up for v brakes which I am told will not work with my new rims.

Depending on the spacing of your brake studs, the width of your rim, and the specifics of your v-brake, it might work with careful setup. But likely it will not, and you may even have to cut away the brake studs to make room for the wide rim and tire.

Short of welding on a disc caliper, you may be able to use a Nexave cassette hub that is set up for a Shimano Rollerbrake. All the models from IM70 on up (larger numbers) have plenty of power and heat dissipation, and they strap to a conventional frame in the same way as a roller or drum brake. You could even use one of the Sturmey Archer drum hubs with a cassette interface.

 

[cal3thousand]

Hey I could fit motorcycle rims... How large of spoke can I fit (with drilling if need be) on a ht3525 crystlyte?

If you are going moto rims, stick with 12G and if going with bicycle rims, go with 14G or 15G.

 

[mr.pibb]

It seems like everyone uses 12-14 gauge on the bicycle rims.
The motorcycle rims I have found accept 10 gauge.
Maybe I can somehow make 11 gauge work in both the motor and the motorcycle rim??
Anyone have any experience doing something like this??

I found this tire seemed to be of interest to me: http://www.ebay.com/itm/291142603913?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT
Hopefully I could fit the full 4 inch, which idk may or may not fit on the rear but no problem on the fork. Then on a 19 inch rim would have a dot load rating of 782 lbs each
With heavy duty spokes I wont even hesitate about loading her down.

Note: the od if I can fit that tire is only 27.2 in (696mm) tall, which actually has a lower overall height than any surly tire on a bicycle rim. ex. endomorph 736mm

 

[mr.pibb]

Ok after everybody said don't go lead acid I did some more research and I think you convinced me. I looked into charging lithium with solar more deeply and with the help of a bms like this one: http://www.gamberbms.com/index.php I should be able to charge the lithium and not have to worry with the solar panels.

I have read a lot on all batteries here before: http://batteryuniversity.com/learn/article/charging_lithium_ion_batteries
But for some reason It was in my head that lithium don't handle a small amp charge well. But after rereading it apparently the amps don't matter(other than super high) you just cant exceed the max voltage for the pack. And I can adjust that with the bms to ensure that they don't overcharge. Not like they ever would anyway when its in use. Only if it was left in the sun for several days.

What do you guys think about the 48v cheapo lithium packs on ebay? I was thinking about running either (2) 20-30 ah packs or one 48v 40ah.

That or I had my eye on the 40ah thundersky types cells. Where can I get them cheaply? Seems like they run $50-60 each and who knows on shipping. I would use this solar controller: http://www.ebay.com/itm/60A-48V-Solar-Battery-Charger-Controller-Regulator-PWM-Charge-Max-PV-input-100V-/111024383643?pt=LH_DefaultDomain_0&hash=item19d991a69b
Its max cut off voltage is 54.8.
And the thundersky batteries nominal voltage 3.2 max 3.6 If I ran 16s the max volatage from the panels per cell would be 3.425. So I would never get a full charge from the solar but it should keep it topped off at 70-80%. Which puts less stress on them anyway. To get a full charge I would have to charge it from ac power.

So what do you guys think? This make sense? Should I go with cheapo ebay batteries or the thundersky type? Or is another way a better route?
Now you have me listening. lol I just want to do this right the first time.

 

[ridethelightning]

i dont know if im happy or not to see commonsense prevail, because i was looking forward to see some entertaining pics of the lead setup :lol:

its sort of in the same league as the guy here on e.s who made a barfridge size cabinet on the rear rack to attatch ryobi drill packs.. ...

if your not worried about weight and bulk too much, and want good cycle life, i would recomend Headway 10ah cells., in atleast 2p setup.

real easy, use locktight on the screw terminals...atleast the quality should be reasonably good.

 

[dogman dan]

You might look at ebay seller sunthing for a pouch type lifepo4 pack. A bit less expensive than ping. Two 48v 20 ah packs would carry well balanced, at about 40-45 pounds. You can start with just one though. 1000 wh will take you a decent distance for sure. 30-40 miles no problem.

If you tow the lead cargo, and just carry light lithium battery and lighter cargo on the bike, you won't need a motorcycle wheel so much.