High power RC motor and drive unit production

[recumpence]

Interesting. It may. But, looking at your pictures, I would say it needs to be motor down configuration to fit.

Matt

 

[etard]

Nice bike, sir! Let me be the first to invite you to start your own build thead here. I wuld like to know your customization process, perfomance, battery chemistry, mods, current changes, etc...

Welcome to the frontier, glad to have you aboard.

 

[j3tch1u]

thanks e, i don't want to get off topic so i'll start a thread when i get a chance. planning to put this bike into production so i'll have a website then. burned out my motor last night going 66.3 kph down a mountain so...i'm going to be following this thread very closely now

 

[CNCAddict]

I'm curious what gearing and voltage you were using...that motor should be fine at those speeds?? I've gone that fast with the smaller HXT motor and never had any bad heat problems.

 

[recumpence]

He is currently using a Cyclone motor right now. That is the motor he fried.

Matt

 

[Miles]

He is currently using a Cyclone motor right now. That is the motor he fried.

and he fried it going downhill? 8)

 

[CNCAddict]

LOL, I missed the part about using the HXT in the future. I want a bike that goes 66km/hr up hill

 

[j3tch1u]

found out it wasn't the motor...it was the controller. i modded the case and might have affected its cooling. i suppose it overheated on the way up. i also heard some grinding near the bottom bracket (it wasn't tightened down properly) so i wrongly assumed i burned out the motor windings. gearbox is 1:9, sprocket 16:18 and 1:2 reduction on the nuvinci. running at 36V. with the nuvinci + motor + batts, my bike is pretty heavy--34kg. coasting down i hit 66.3 kph and overtook my friend on his orbea road bike at a nice clip. i have a positioning seatpost and had it in the full laid back position. in conjunction with the titec h-bars i can get a really low tuck. the cycle analyst sits right in front of my face like a hud which is nice cuz you don't wanna take your eyes off the road too long. i'm planning to add pegs to the rear suspension to test how a forward batman style tuck feels. i'm in taiwan and we have some pretty steep mountains here. so with the HXT i'm hoping to get a little "push" off the top

 

[recumpence]

I just heard from Jason.

The FW adaptors are done and will be shipped tomorrow! I should have them next week..

I will be machining more pulleys over the next few days along with picking up the last few bearings and shafts to complete the first run of drives.

I can taste it now!

Matt

 

[GGoodrum]

Sounds good, Matt. Those adapters are going to be quite handy, I think.

I've decided I'm going to re-power my Townie with the Neu 2215/P62, combined with a single-stage edrive. Not sure if ththis can be the belt version, or if the chain drive will be required. With the 6.75:1 reduction, I really only need a 2.5:1 reduction on the edrive, so I'm thinking the belt might still be okay. What do you think?

I'm still trying ot figure out how to mount the edrive, but I think it might be easier on the Townie, where it will go on the downtube. What I'm thinking is that I will drill a couple holes through the downtube and bolt two aluminum plates to the side of the tube. The plates will have slots in them that will match up with the side holes on the edrive mount. This will allow the edrive to have some adjustment room, in order to put tension on the chain to the crank.

The other idea I had would be to use a 4" long U-shaped piece that can attach to the downtube with a couple of U-bolts. The sides would have the same slots, that would bolt to the side holes on the edrive. I like this option because it is less intrusive to the frame. If the sides were tall enough, there might be room for the controller, and the rest of the electronics (throttle/BEC board, ET eLogger, etc.

How wide is the mount? I think one time you told me 1-1/4", but I can't remember. I think this is also the diameter of the downtube.

-- Gary

 

[recumpence]

The mount is 1 and 1/8 inch thick with 3 inch distance between holes.

You will need chain drive to handle the torque for sure.

You can go ahead and ship me the motor and I can begin your drive. I will be ordering the chain and sprockets from SDP specifically to suit your drive as well as mounting the motor for you.

Do you still have my address or should I PM it to you?

Matt

 

[GGoodrum]

The mount is 1 and 1/8 inch thick with 3 inch distance between holes.

You will need chain drive to handle the torque for sure.

You can go ahead and ship me the motor and I can begin your drive. I will be ordering the chain and sprockets from SDP specifically to suit your drive as well as mounting the motor for you.

Do you still have my address or should I PM it to you?

Matt

Yes, I have your address. I'll send the motor/GB combo tomorrow. The output shaft on this is 12mm.

Thanks -- Gary

 

[CNCAddict]

Hey Guys, I'm dropping the outrunner and going with a standard inrunner motor. It's up to you guys to determine the maximum motor OD. The smaller the OD the less torque and power for a certain motor length...and added motor length means placing it between your legs could be a problem. Right now I'm running simulations on an 80mm OD stator which means the motor would be around 86mm OD. If that's too big just let me know and I can shrink things up a bit. This motor will have less cogging, run smoother, can be sealed...but also has a bit larger OD and will weigh a bit more than the outrunner. I'm also thinking about mounting the motor to a right angle gear drive. So the motor would sit lengthwise along the frame. This might make it too ungainly to work with Matt's drive so that's not a good thing...but it would make the motor length a non issue. Give me your 2c

 

[Miles]

David,

I always hoped you'd go for an inrunner in the end 8)

I'm not crazy about the right angle drive idea, though - I'd prefer something more like the MEGAmax 3.7.

Maybe even 100mm OD 65mm length?

 

[GGoodrum]

Hey Guys, I'm dropping the outrunner and going with a standard inrunner motor. It's up to you guys to determine the maximum motor OD. The smaller the OD the less torque and power for a certain motor length...and added motor length means placing it between your legs could be a problem. Right now I'm running simulations on an 80mm OD stator which means the motor would be around 86mm OD. If that's too big just let me know and I can shrink things up a bit. This motor will have less cogging, run smoother, can be sealed...but also has a bit larger OD and will weigh a bit more than the outrunner. I'm also thinking about mounting the motor to a right angle gear drive. So the motor would sit lengthwise along the frame. This might make it too ungainly to work with Matt's drive so that's not a good thing...but it would make the motor length a non issue. Give me your 2c

Actually, I think this is good news. I've never thought that having spinning cans was a good idea on a bike. Forgetting the safety issue, it makes it harder to protect it from the elements. A sealed inrunner is perfect, in my opinion.

I don't think 80mm will be too big at all. Man, that will make this a real torque monster. I think optimising it for around 50V, would be good as well, something that will still work with the controllers we have available. I'd like to see the kV in the 100-120 range, if possible. That will simplify the gearing a bit more.

Speaking of gearing, I love the idea of using an angled drive, and mounting the motor length-wise on the frames. Years ago I did something similar, using helical cut beveled gears, on an electric conversion kit for the Raptor glow-powered helicopter. It used a mod 1 gearset, with a 2:1 reduction.

There are larger gears that go as high as 3:1 and 4:1, listed here: http://www.qtcgears.com/RFQ/default2.asp. You just click on "Bevel Gears". I think a mod 2 gearset size would be more than enough to handle the power. We were runnig 4kW peaks through the mod 1 set, and had zero wear that I ever detected.

Anyway, Matt's thread is probably not the place to discuss this, so why don't you start a new thread on this new inrunner motor idea?

-- Gary

 

[recumpence]

Right angle gears are less efficient, though. I like the idea of large OD with short can length.

86mm is doable. I would like to see a maximum length of 2.5 inches for the can and 4 inches overall for can and shaft combined.

Matt

 

[CNCAddict]

http://www.endless-sphere.com/forums/viewtopic.php?f=28&t=8057 <-my responses are on this thread

 

[GGoodrum]

Right angle gears are less efficient, though.

The spiral cut bevel gears are pretty efficient, but the biggest problem is that these things are uber-expensive. Plus, they need a lot of finishing work. We ended up having to do a threaded brass hub for the big one, and had to turn them down quite a bit, to remove some weight. Even the mod 1 gears were very heavy, so I'm guessing the larger version would be real pigs, weight-wise.

Anyway, it sounds like David's leaning towards larger diameter and shorted cans, which would obviate the need for angled drives.

-- Gary

 

[j3tch1u]

david, i second the inrunner proposal. as for size, with my cyclone extended bb spindle and truvativ isoflow cranks (large q-factor) i have 170mm clearance between the crank arms. the spindles are available off-the-shelf so this may be one design consideration.

currently trying to fit:
- hxt 95mm
- dual matex gearboxes + spacer 33mm
- mount width 8mm x 2
- dual freewheel with 1-way roller bearing 35mm
= 179mm

in this case, an 80mm motor length would be perfect. as for diameter, 75mm would match up with the matex 75M gearboxes: http://matexgears.thomasnet.com/viewitems/all-categories/torque-range-45-300in--lbs-?&forward=1

next step up is their 120mm series but since the heavy duty 75 can handle 1200 kg-cm torque, i don't expect anyone would need to go that big. anyone have any experience with these?

 

[MitchJi]

Hi,

I had this idea a couple of weeks ago and Gary's desire to use a downtube mount triggered my decision to post it.

I'm still trying to figure out how to mount the edrive, but I think it might be easier on the Townie, where it will go on the downtube.
-- Gary

http://www.endless-sphere.com/forums/viewtopic.php?f=28&t=7180&st=0&sk=t&sd=a&start=330#p117611

Direct bolt-ons are always preferable. However, for now, I need to get the drive itself finished (all parts finished) with the basic mount for those who don't mind doing a bit of fabbing or going to a welding shop for mounting before I look to make any kind of universal mount.

I am not looking for tons of sales. For now, I am making a high-end drive for the determined few who really want the best, custom setup. Once the drive proves itself, I can see how much time I have on my hands to increase sales by offering some kind of bolt on mount. There are problems with bolt on mounts, though;

#1 All bike are different. No mount would be truely universal.

#2 The drive, itself, is very high quality. A universal mount using u-bolts or the like would look out of place. They may work, but not as something I can just include. I would get comments like "Nice drive, crappy mount." For now, the mounting will be left to the individual. I may be able to do some simple custom stuff for the occasional customer who wants amount made to his specs. But, in general, at least a bit of fabbing will be needed to mount the drive (at least untill I make sure I have time to fill the demand for more drives). :wink:

Matt

At first I thought a universal mount wouldn't work very well. Almost every bike is a little different. Then it occurred to me that a very large percentage of bikes have slanted down tubes. I think you could design and sell very high quality downtube mounts, that will work on a lot of bikes. You might want a semi-custom mount (customer provides their downtube diameter). A similar concept (probably a higher quality implementation) to one of the following examples.

The Elation Kits use chain or cable for the clamps so they fit a wide range of tubing. (I don't think clamps are sufficient unless the mount has some provision to prevent rotation on the tube).

Tube Size Diameter from 30mm to 55mm. Smaller and larger tubes can be accept by modifying flexi-clamps yourself

You could even sell complete kits (with all the crank parts) or complete kits minus batteries. If you want to provide parts to more people or you want substantial sales volume I think this would be a good way to go. There are several companies selling this type of kit and if you design a mount that is half as elegant as the drive itself you would blow them away for quality and performance.

 

[recumpence]

I am always willing to look at various options for my drive. However, with larger sales numbers and more complete kits comes a few negatives that I do not want to deal with;

#1 Customer service. As you increase sales and make more complete kits, customer service begins to really dominate your time. Also, the more complete the kit, the more willing a beginner will be to buy it. I do not want beginners buying my drive. This is far to complicated for someone who is not already technically inclined, or at least VERY determined.

#2 Liability. Custom stuff is not a liability issue. However, large production numbers create liability issues.

I went through this with my RC heli products. I ended up spending HUGE time answering questions and providing customer support for very simple things that bogged me down horribly. Gary can relate to that situation too. :wink:

Right now I am content to get the drives out there and in use. It is easy to design various style mounts for easier installation later. Also, with the power these drives will be puting out, a clamping style mount will probably move on the frame. I think a welded or drilled and bolted mount will be required to handle the power.

Matt

 

[Ypedal]

I fall into the Very determined category lol.. and slightly insane.. that helps too !! :wink:

 

[MitchJi]

Hi Matt,

if you design a mount that is half as elegant as the drive itself you would blow them away for quality and performance.

Also, with the power these drives will be putting out, a clamping style mount will probably move on the frame. I think a welded or drilled and bolted mount will be required to handle the power.

Matt

I'm sure you could work out something better than the following idea but I think it would work well.

A clamp three to six inches long, sized to clamp tightly on the down-tube, with something like a bike inner tube on the down-tube, under the clamp would be pretty strong. Then another similar clamp on the seat-tube with a strut or plate bolted to the right side of the down-tube clamp and the right side of the seat-tube clamp with another strut or plate connecting the left sides.

 

[fechter]

If the clamping arrangement is triangulated so there are at least 3 clamping points, it should remain solid. The further apart the 3 points are, the less it will be able to flex (assuming no flex in the motor mount). It should be possible to estimate the ideal clamp spacing to minimize flex and cost of material needed.

The real challenge is to come up with something that's as universal as possible to fit the vast majority of frames. Full suspension frames are even more varied in geometry and generally more difficult to attach to.

Some kind of modular approach would seem to make sense where you have a core unit that's universal, and a set of parts for mounting to the frame that may come in various shapes and sizes to cover different frame geometries. Minimize the cost of the frame specific parts. Make only what's in demand.

 

[MitchJi]

Hi,

If the clamping arrangement is triangulated so there are at least 3 clamping points, it should remain solid. The further apart the 3 points are, the less it will be able to flex (assuming no flex in the motor mount). It should be possible to estimate the ideal clamp spacing to minimize flex and cost of material needed.

One clamp on the down-tube and one clamp on the seat-tube connected by a struts or plates form a triangle. In other words only two clamping points are required for triangulation with many or even most bike frames.

Full suspension frames are even more varied in geometry and generally more difficult to attach to.

Many full suspension frames have round or almost round angled down-tubes. Mounting on the down-tube and connecting via a freewheeling crank avoids a lot of the issues.

Some kind of modular approach would seem to make sense where you have a core unit that's universal, and a set of parts for mounting to the frame that may come in various shapes and sizes to cover different frame geometries. Minimize the cost of the frame specific parts. Make only what's in demand.

Agreed. Matt has already done the difficult part with his "core unit" reduction module. Mounts for this drive that will work minor customization on many frames are relatively easy.