YUBA MUNDO e-bike,10kw golden bldc motor installation help

[orange streak]

I need advice on preparing my e-bike for installation of the 10kw golden motor, just like liveforphysics has done for his bike. I plan on using a steel framed yuba mundo v4 bicycle. I will hopefully be replacing my hub motor mid drive kit with a new mount made from urban commuter to properly fit motor. I need help to make sure every thing is up for the abuse of the power to run through the bike & its parts. This includes chain, & sprocket, wheels, bolts, brakes, upgrades, etc. Here is a work in progress picture of my e-bike which has a 7kwh reinforced battery supports, with 103.6v 68Ah nominal voltage. A 90 pound panasonic battery with only a 24fet lyen controller.
I currently have 180mm disk brake up front & a rim brake, & just one rim brake on rear wheel. Braking power is good for current setup of less than 35mph, but may need upgraded. Need to have right parts to make as reliable as possible high powered e-bike. I know how much torque this motor has and speed & is a dangerous wheely machine, capable of 90mph+ with my current voltage. There is a good 10 inches in frame to mount the motor and I will have it aligned for chain a sprocket to mount to the left side wheel. Will my bike turn out successful?
Its ready for decals.


View attachment 2

 

[orange streak]

I was going keep using the disk brake holes for the sprocket, but was told that they would not take the abuse from the torque? Im going to also try a 26" mag wheel on back to get around spokes, if that fails I may try a 19" moped or motor cross wheel. Another issue was to find a super strong chain tensioner that is suitable. The mount is going to be made in a way so the user can still peddled at low speeds of under 35mph, so to increase milage. I assume this motor is has as or more efficient than the hub motor besides its increased weight while used in cruise control. I was told I should use 415h chain to a large steel sprocket, maybe a 4:1 ratio to account for high rpms. Need some details to finish up this bike & live up to its name.

 

[orange streak]

The chain I'm using now is 1/8 & has limited room to fit on the straight sprocket. If I go with thicker chain the alingnment need moved away from chain stay, but I'd need a sprocket that is concave to move chain line inward more. I have no experience on this issue. Running chain on left side seems best but I lose the ability of a disk brake. I like the feel of peddling to have something to do.

 

[orange streak]

IS ANY BODY ABLE TO OFFER ANY ADVICE???

 

[terminus]

Try not to die?

 

[orange streak]

Try not to die?

I thought as much, this might be a topic few are willing to respond to. I am really wanting to confirm now, is I've request motor info and it has 6 hall wires, so I assume at this point I am able to just correctly hook up to my 24fet lyenn controller? Set the number of magnets with cycle analyst, & good to go. If all else is successful I will take caution, & low speed drag some trucks and cars & give them the idea, electric is better.

 

[Voltron]

I think you're seriously underestimating the challenges on mounting that... It's going to be so wide that to align the chain its going to be sticking out into the chainline on the other side, and may even need a special wide crank spindle to get the pedal past it. I'm already running into that getting this motor mounted, and it's a lot narrower


Then if you get it mounted, there's a good chance it will want to pull the axle forward out of the forward facing dropout of a Mundo. I'm all for overpower, but you might want to work up to it in stages.

 

[LI-ghtcycle]

Crazy!

I like it! :lol:

I don't have any specific advice to offer yet as I am about to embark on similar territory for the first time (stretch cruiser frame with cro-motor shooting for 10kw eventually, taking baby steps up from 72v at this point).

I do however believe you and I both will start experiencing some serious frame flex issues, you're probably in better shape in that department, but still, your frame is probably better suited for it's intended purpose than 10kw to the rear wheel, and I expect you may have issues with that motor flexing the frame enough to throw chains, but I have no practical experience at 10kw with either frames as of yet.

Good luck!

P . S . I have a 24" BMS cruiser style frame that I built just for track day speed, and I will most likely end up going with the Cro-Motor built into a moto wheel to go for serious speed as it's just a much stronger set-up if the stretch cruiser frame starts to get squirrley (as I suspect it will) and probably swap in a MXUS hub motor in place of the current one on the Cruiser.

 

[orange streak]

I think you're seriously underestimating the challenges on mounting that... It's going to be so wide that to align the chain its going to be sticking out into the chainline on the other side, and may even need a special wide crank spindle to get the pedal past it.
there's a good chance it will want to pull the axle forward out of the forward facing dropout of a Mundo.

Indeed it may get in the way of peddle chain line, I still have to make some measurements and get perhaps a 3d drawing to my kit builder. I can see about mounting it up a little higher if that helps. & good point how am I going to keep the wheel axle from slipping out from so much motor torque? Stuff I didn't all think of comes to play & I'll consider it in design.

 

[orange streak]

Crazy!

I like it! :lol:

Good luck!

P . S . I have a 24" BMS cruiser style frame that I built just for track day speed, and I will most likely end up going with the Cro-Motor built into a moto wheel to go for serious speed as it's just a much stronger set-up if the stretch cruiser frame starts to get squirrley (as I suspect it will) and probably swap in a MXUS hub motor in place of the current one on the Cruiser.

Might I suggest if you have room to mount a cro motor then I reccomend the even better hub motor: Q's v3 hub motor which has thicker & deeper cooper in the strator slots. My friends are go 80 to 85mph with thier setups with 200amp Kelly controllers! The voltage they use is 134v!

As for luck. My kit builder seems up for the challenge to get it to work mounted with aluminum side plates. I hope I manage to get it fitted, Thiers only so much I can do with alignment & chain position up & down. I'm hard at it to make it work. Nice bike!

 

[orange streak]

I had a idea! The motor needs not interfer with the chain line on peddle side so. If my mount has motor position far on left side & the extra long shaft could have chain line come out to the sprocket then bring the chain line in where it needs to be with the freewheel sprocket on the inside of shaft to go back to the rear wheel. This runs the power through the freewheel sprockets if it takes all that power! And It would help to have sprocket that freewheels in the opposite direction so wheel spins freely without turning motor. On top of that I doubt it is easy geting 5/8 freewheels that mount on shaft for a bigger chain size for recommended 415h. This is going to be a challenge on my part & I got questions that need answers. Pic of my motor mount for visualizational understanding.

 

[flat tire]

You need more weight over the front.

 

[orange streak]

You need more weight over the front.

I'll explore the option for more battery weight in the triangle of frame but I doubt it will make too much of difference & cost even more. No sence in adding just weight up front & worsen milage.

 

[orange streak]

All recommendations are welcome, to make this a rare one of a kind e-bike with crazy detail. I need to know any ideas (what to use for the chain tensioner, which I was told should be spring tension?),
I have no idea what to use for this high power torque setup. If my gears will be higher then my braking solution's can be solved with a sprotor brake caliper would do the trick for sufficient braking power. It sure is a challenge to work around the battery and spokes, but I've managed. All welds will be paint restored to similar tangerine color.

 

[orange streak]

The latest update is that the 10kw motor will not fit properly between the peddle crank arms & still keep peddle chain. So after examining the issue I have notice the 5kw motor is 5 inches in length an just barley fits! So its a question of how power capable & top speed can be achieved? This motor for me would be compared to how well does it out perform a cromotor hub or Q's v3 hub motor with 50mm wide windings.

 

[LI-ghtcycle]

All recommendations are welcome, to make this a rare one of a kind e-bike with crazy detail. I need to know any ideas (what to use for the chain tensioner, which I was told should be spring tension?),
I have no idea what to use for this high power torque setup. If my gears will be higher then my braking solution's can be solved with a sprotor brake caliper would do the trick for sufficient braking power. It sure is a challenge to work around the battery and spokes, but I've managed. All welds will be paint restored to similar tangerine color.

View attachment 1

Love that Sproter!

I might have to steal that idea on a later build :wink:

You're up against the main difficulty with such a wide motor, but you could use a simple jackshaft between the pedals and rear sprocket to move the chain line above, below, or around it.

You could use a rather large sprocket on the crank and "ghost ring" in between also to give you more spacing, just brainstorming.

Here's is a couple pics of the "ghost ring" set-up we tried while sorting our our chain lines:

 

[LI-ghtcycle]

Even easier, you could always use a recumbent style "double pulley" I forget the proper name, and run your chain line like this:

 

[cwah]

35mph on an un-suspended heavy bike?

You're going to loose spokes very often

 

[LI-ghtcycle]

35mph on an un-suspended heavy bike?

You're going to loose spokes very often

That's more of a thing when you have a hub motor, mid-drive not so much, I have gone 35+ MPH pretty regularly, with no issues, less loading on the spokes and less un-sprung weight in the wheel.

I guess if you ride on rough ground that will be more of an issue, where I am in Oregon City, the roads are very well maintained and smooth. 8)

 

[orange streak]

Even easier, you could always use a recumbent style "double pulley"

I like that idea & it may come in handy if motor is to close to chain line. Like I said I have to unfortunately use the 5kw motor but it fits with its given measurements.

 

[orange streak]

35mph on an un-suspended heavy bike?

You're going to loose spokes very often

Yeah its a rough ride if the road isn't smooth. But it takes it all fair. Need a suspension seat post for sure! I love the look of people installing triple crown suspension forks on e-bikes but I'd lose some milage and it would have to be right size. The front wheel will be for now a bicycle mag wheel & will have a solid axle put in. I can't get any email responces for people who are using 21" motocross rims with 2.75 inch tires. I'll keep messaging, & as a rear wheel should be better. Hit a curb & bent a back rim already with all that battery weight, I wasn't going fast over the bump either! Other frame problems I see are the forks are not the strongest, I really need a very beefy fork with heavy duty dual disk brakes, probably 203mm disk rotors at high speeds of 40 & 50mph with this weight.

 

[orange streak]

Can't I keep the axle from slipping out of dropout? That's waiting to happen on a bad day. I almost used to not be able to torque a quick release rear wheel down tight enough & have wheel slip out from motor power, not fun when at high speeds!

 

[LI-ghtcycle]

Can't I keep the axle from slipping out of dropout? That's waiting to happen on a bad day. I almost used to not be able to torque a quick release rear wheel down tight enough & have wheel slip out from motor power, not fun when at high speeds!

Do you have a picture of your drop-outs up-close?

Many have used some form of clamping drop-outs to solve that issue, I made a variation on the first version of this bike:

https://endless-sphere.com/forums/viewtopic.php?f=28&t=44997&start=50

Somewhere there is a thread with various styles of clamping drop-outs that are much simpler and might be more useful for you situation.