Copy Grinhill! lil help please :)

J

Joepostal

100 W
Joined
Apr 8, 2008
Messages
123
So I been lurking for quite a while and I love Grinhill's design. So I would like to copy it. :D So much has changed since December and Matt's amazing recumbent. I have been trying to catch up for the last couple weeks.
Grinhill you did an amazing job! http://endless-sphere.com/forums/viewtopic.php?f=28&t=9172

Since I finally have a few bucks to actually build something!!! Here is my parts list...

Motor - TGY AerodriveXp SK Series 50-65 270Kv / 2100W - should be easily upgraded ( see controller )
http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=7709#
I have decided to go with the 63-64 instead. This way I have some wiggle room.
http://www.hobbycity.com/hobbycity/...TGY_AerodriveXp_SK_Series_63-64_230Kv_/_3150W
I will do preemptive CA glue and check the bearings. If they are not very good I will replace them.

Controlller - TURNIGY Sentilon100A HV 5-12S BESC (Ver4) - this should provide plenty of overhead.
http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=4691

Battery - ZIPPY Flightmax 5000mAh 6S1P 30C
http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=8590
What would be a decent charger to purchase for this battery?

Lower Pulley - The spoke-mounted pulley from Golden Eagle.
http://www.bikeengines.com/orderpage2.htm

Upper Pulley - no sprague clutch just attach pulley to motor. Have to drill out to 10mm.
https://sdp-si.com/eStore/PartDetail.asp?Opener=Group&PartID=59699&GroupID=346

Throttle current limiter.
http://endless-sphere.com/forums/viewtopic.php?f=28&t=8160
I got in on the first batch so I will be able to regulate power.

(edit removed obsolete information updated links, corrections)

Thanks everyone,
Joe
 
Hi Joe, welcome :)
Firstly, what kind of bike do you have?
What sort of range are you looking for?
Commuter or just for fun?
Are you aiming for top speed, fast acceleration, reliability...?

It helps to know a little bit more about what you want to accomplish. If you give us some more information maybe we can help you pick your components to better match your goals.

Knowing what you've told us, my first suggestion would be to go for one of the bigger motors. The Turnigy 63-64 is only $6 more, and you get a much larger motor. This means that for the power you plan to use, you have more thermal mass and surface area to dissipate heat. In addition, you get a lower Kv ratio, so you don't need to use as large a reduction.
As for a charger, any of the 6s chargers on Hobbycity should work fine. I believe the cheapest one is the Turnigy Accucel-6 for under $40. For my 12s battery, I bought a G.T. Power 200W charger and a power supply for $120.

For power transmission stuff, SDP/SI is the place.

I have a few more suggestions but I would like to hear first a little more about your ideas.
 
Darn, well I made it to the end Fechter's throttle thread and they are not completely ready...

I doubt I will need current limiting at all but I want to build two bikes and the one for a friend has to be as bullet proof as possible.

I looked at every site on the Pulley resources thread and didn't find a single pulley that had a sprague clutch in it. I must be missing something here.

The clutch has to be pressed fit? Then I need to drill out the Pulley to fit onto the sprague? Not having done anything like this before is making me crazy :)

Any help will be greatly appreciated!!!

Joe
 
Hi oofnik,

Heh, I have been reading here long enough to know that I should post my intended results...Well after seeing Grinhill's design I figure that range is just a matter of adding more batteries and his performance is roughly what I think would be great.

My design goal right now is for 10 mile range moderate acceleration and decent top speed say 25mph. I am not thinking about laws. I can clearly see that getting one thing working well would be easily modifiable into something greater so I just want to get that first one under my belt. I only drive 2 miles to work and live in Boulder, CO. My commute is almost completely flat but I can find some nasty hills if I want to stress things. I hope Matt keeps making reductions for people so when I am ready for my next project I can get something made by him. I have a cx450 that I am modding but my first project is my commuter hardtail.

The motor suggestion is exactly what I was hoping for, It should run cooler, let me change pulleys if I don't like the performance and I could add/change batteries if I want more range. As for the friends bike I want to give them a toy to get them most the way to work and have them recharge at work in a 5lbs package.

I am so looking forward to having some parts to play with!!! :)

Joe
 
After checking out the other options for well powered ebikes on all turnigy motors...
A quick chart;
turnigy 50-67 434g 2100w 270kv
turnigy 63-65 690g 3160w 230kv
turnigy 64-75 840g 3250w 170kv

The 50-67 with a 14 tooth to 148 tooth drive gives roughly 44kph, 28mph on a 6s1p battery. That is the smallest pulley I think I have seen? With either the 64-65 or the 64-75 there are much more options for ratios but there is a little more weight. How much difference in heat between them and the 50-67? I think I would rather get the 63-65 if the heat is not much difference between it and the 64-75. I bet this has been answered somewhere but do lower ratios produce less heat?

I wish I could remember everything I have read on these forums the amount of information is enormous.

Joe
 
Well, going by this:
My 2007 HTD replacement belt is marked Gates 16355M09K. Deciphering the code, this likely means
9mm wide, 5mm tooth pitch, 1635mm length

I have the same vintage belt, bought at the same time, on my bike. The belt currently has 1150 miles, and has stretched approximately 6mm. This slack is taken up by the idler pulley on the motor.

The above referenced article lists the OD drive ring diameter as 17". The 17" measurement is to the outside flange that serves as a keeper for preventing the belt from falling off the side of the ring. The diameter of the drive ring which is in contact with the belt is actually a little smaller at 133cm.

The drive ring has corresponding 5mm pitch teeth molded into the contact surface. However, the teeth are only molded into 90 degrees of the ring, at every other 90 degree interval. This allows the drive ring to be molded as a single piece (missing teeth areas needed for mold release).
Click to expand...
drive-gear:drive-ring

14t=1:19.1
13t=1:20.6
12t=1:22.3
Click to expand...

From here: http://www.motoredbikes.com/showthread.php?t=8033

That would mean it has 268 teeth, it is HTD in 5mm pitch, 9mm wide. So I think you want a pulley with about 20 teeth on it if you are going with the 230 KV. In that case you need this pulley:
https://sdp-si.com/eStore/PartDetail.asp?Opener=Group&PartID=59699&GroupID=346

I am glad someone has went this direction, there is also this from erth64net:

http://gregg.berkholtz.net/blog/archives/33-The-Recchetta-my-eBike-project.html

Greg has addressed many of the issues you are talking about.
 
Ahh That is great information there. Thanks Miles and Etard.
So if I get this roller bearing HLF 0822 http://www.vxb.com/page/bearings/PROD/8mm/Kit8238

And the pulley you recommended I will need to drill out the pulley to 12mm? I still don't get how it stays on the shaft although it seems I could secure the pulley to the bearing easy enough.

Or just mount the pulley and sometime in the future look for a controller that supports regen... It would be cool to have a throttle you could spin backwards to slow down.

Thank you very much for your help so far. I have all these shopping carts open just waiting for me to click :)

[edit]
Shaft: 10mm on the 63-65 -- Big oops above
now I am looking for a different pulley and clutch.
 
Joepostal said:
My design goal right now is for 10 mile range moderate acceleration and decent top speed say 25mph.
Click to expand...

lol. You should have no problem achieving that. But I will add to the suggestion pile that a bigger motor is better. Less likelihood of exceeding its power limitation and correspondingly more reliable. Plus, it gives you more head room to grow which it seems most of Endless Sphere's not-so-law-bound members like to do. Also, it's almost always better for extended hills due to heating issues.

10 miles though. If you're not planning on pedaling at all, I'd suspect you'll probably need at least 360 WH as a bare minimum(that's assuming near-ideal environmental conditions) or 500 wh if you want some reasonable buffer room to give you that 10 mile range on all but the windiest of days. If you're planning on 6s which is 6*3.5 volts = 21 volts which means you'd probably need 20Ah (21 volts*20 Ah ~ 420 wh). It's almost always better to run at a higher voltage(Unless you get woefully addicted to the speed!), then you could run at, say, around 40 volts and only need 10AH or so. Either way, it still equates to 4 of 5000 mAh 6S packs. If you're not adverse to pedaling and don't get addicted to speed, then you could chop that capacity requirement considerably.

Also, while some make the suggestion of going with the lower KV motor due to easing gearing reduction issues, you might also want to consider the effect of necessarily increasing the internal resistance to do so. If your power demands are modest(say 25), then it shouldn't matter, but it becomes more important if you expect to go more than 45 mph on the flats or greater than 30 mph up a steep hill.

If you want to get an idea of what you might expect from your bike with different set-ups(With different gearing, motors, etc.), see my simulator(In my signature line). Several key things you'll want to watch out for - check to be sure the heating is less than 1000 watts or so or you might have issues with heat. I recently was designing my own R/C ebike and maximizing the back sprocket for high speed up a hill ended up generating more than 3000 watts! It turned out that it's max speed would've been 40 mph. By manually increasing the back-sprocket value, I ended up decreasing the top speed up the same hill to 36 mph, but ended up only getting 700 watts of heat which is far more manageable.
 
Hi swbluto,

Yeah this is getting nuts but I pulled the trigger on a bunch of stuff. Basically I purchased 2 of everything on the list... Thankfully my friend has a lathe with 2 chucks so I can guarantee drilling out the 8mm pulley to 10mm and I am going to skip the sprague for now.

I don't have any objection to pedaling but I am thinking I am going to put a spare battery in another water bottle. If you drain one then you just grab the other one out of your pack place it into the drink holder and off you go. Once you get a bike running the options are endless. A problem with charging is do I really need a full blown RC charger at work and at home or is there a trickle charger I can use while at work?

I went with the 63-65 but now I am going to run your calculator and cry :) haha

I saw that Grinhill was getting around 8 miles off his 6s1p pack (at least I think I did :) ) I am certain I won't be able to feed that motor with just 1 battery but I just can't wait to get my feet wet. I have been reading the forums for months and waiting to have some cash but I saw that using RC motors was coming on strong so I waited more, got out of debt and now I can put a few bucks to some parts plus benefit from all you mad men doing 40mph+!! WOOHOO :)
 
OMG I DONT HAVE JAVA... had this computer for 3 years now and have avoided java for as long as possible.

I think the idea is simply brilliant but the execution not so much haha
 
Oh well, it's not necessary. I believe there are "java compilers" that produce an executable, but I would have to wonder if it's worth a java-hater diehard. Do you routinely block .net applications, too?

Anyways, proceed ahead. It seems that a gear ratio of about 30 or so would work well with a Kv of 270 on 26 inch wheels. That's more of a "hill climbing", high-efficiency but a little slower kind of ratio. For speed on the flats, it seems something like 12-20 would be desired.
 
Gidday joe, and welcome to the fun.

Did you end up going for the 63-65 230Kv motor? If I was doing my build again I would probably go with that one as the 50-65 does warm up quickly after an uphill run.

Did you go for an aluminium or plastic small pulley? Mine was plastic. The one-way bearing was definitely the fiddliest part of my build, and going straight on the motor shaft sounds like a quick way to get you rolling. I used epoxy adhesive to glue the one-way bearing into the pulley, the glue is holding up well. Unlike the bearing itself, which is getting fairly noisy on the overrun.
 
Oh Hi Grinhill! Nice work on your bike, I dig it, I was just answering swbluto,

I am going with 63-65 is 230kv so I have the 20 to 268 and 5mm pitch gearing to a 26 inch wheel... Using the aluminum one.
If I am using the calculator correctly that should be top out about 36mph, 14teeth would be 25mph.

But set to 42 volts with a 22 tooth and top speed over 75... I must be doing something wrong. Or this is going to be one hell of a spoke breaking adventure :twisted:

I will probably fiddle with a few upper pulleys and find the best performance after I get up and running.

The heat generated is not looking correct either, 150 heat at peak? I will have to poke around some more.

I don't have anything against java just never found I had to have it till now but it was a good run with out it :)

Thanks that is a neat program.
Joe
 
That's strange as I haven't run into that problem yet. Could you save your data(There's a save command in the File menu near the top left) to a file and post it on here using the "Upload attachment" that's at the bottom of the page where you type a reply on this thread?
 
Changing the back sprocket value seems to change its speed by 1 mph or so. If you're "nearing the top of the power hill" at that kind of "power needed to go that fast" for the gear combinations you input, you'll see little change on the flat's top speed.

But, one problem I noticed is that the batteries have an internal resistance of .3 ohms which is pretty high for 30c zippy's! My 2C ping has an internal resistance of .25 ohms or so but 30c zippys would have an internal resistance much less, like .05 ohms at 42V 5AH. It'd be like .025 ohms at 42V 10AH and 21V 5AH. You should notice a difference changing that.

Also, I didn't find any 70+mph speeds. Possibly that was the efficiency box?

By the way, I'm checking out the edited specs and it looks like you're going to have a sweet ride! I'm thinking you'll find you can go a little faster than 25. :wink:

(But, just a word of caution, oofnick had a single small hobbycity motor like that and it seems the magnets come off when pumping 3kW through the motor with the stock glue, so you might have to do some regluing sooner than you expected. Currently, it seems that JD weld might be a good glue to use along with scuffing the surfaces that attach according to Johnholmes, but that's currently an open question in the forums.)
 
Yeah I was looking at the motor simulator graphing... I didn't realize until later that it was just what the motor could do given no resistance? Is that what motor simulator graphing does? The predictions show a totally different story.

Still new to the program but nice work there I am certain it took a ton of effort to get it working. So thank you for the tool :)

When ever all the parts show up and I build it I will put real world numbers in my build thread so you can fine tune your program if you still work on it.

I just realized I totally forgot to order a pair of servo emulators.
 
Joepostal said:
Darn, well I made it to the end Fechter's throttle thread and they are not completely ready...
Click to expand...

It seems like he just completed a batch so you might be able to get one...

Also, the motor simulator graph shows what you can expect various things to be at different speeds. But, just because your motor could potentially rev your back wheel to 70+ mph doesn't mean you'll go 70 mph in real life as real life tends to create air resistance that likes to push you around. In the graph, there's also a "power needed" curve available that'll show you what kind of power you'll need to a given speed - As you go faster, you'll need more and more power to sustain higher speeds. The speed you'll eventually obtain is where the power your motor is putting out is equal to the power you need, so the true speed will be when the "power output" and "Power needed" curves intersect.
 
Ahh, cool!! that is neat.

Now I am going to be looking at that 42volt number all night :) Hope they get a bunch of stuff in stock in the next few days, most my order is back ordered.

I am already thinking about pulling the motor apart and doing a CA preemptive gluing.

I will see if I can get in on that first batch of current limiters! Thanks for all the help swbluto and everyone else.
 
Hey thanks for the links etard. I think it is kind of funny how we all reach our limit of how technical things can get. I like the 4th link where I can put in 3 numbers and see a top speed :)

I can't wait to just have 3 gears and just change them to see how things go... Thank god for really smart people :)
 
Well I got the batteries and motors and esc. Plugged them all together and the motor shook back and forth instead of spins.
I suppose I got a bad controller although I didn't program the controller first and it says that the large motors need high timing or the controller could fail. The new motor seemed very smooth but I think the violent shaking shook a magnet loose. Anyone need a magnet testing controller. The weird part is the wires from the batteries to the controller were hot but I never saw any magic smoke escape... So I still think I just have a dud controller.

Oh well, that is why I bought two of everything hopefully later tonight I will get the remaining good motor spinning while I take the other one apart and learn how to rebuild them. The over all quality doesn't seem to bad, on hobby city they say Japanese bearings but on the case of the bearings is printed Singapore :) obviously glue and new bearings is a must but maybe even re-turn the wire and harden the shaft is in he works as well. Thankfully my other bike is a Matt drive :)

I will take some pictures of the parts so people can get a feel for size and quality.
 
Yeah, the second controller runs almost beautifully. I have the throttle set to very soft start and high timing.
Here is a video of the motor running in a vice. I will test it with other start settings. I am really disappointed that the first controller didn't work.

[youtube]DBtSjjdc5OQ[/youtube]

When I tear down the first motor I will make another video :)

Cheers
Joe
 
You must log in or register to reply here.

Similar threads

Metallover
So I've Got This Mountain Bike..
Replies
16
Views
2,933
Timma2500
Timma2500
M
benefits of non-hub motors
Replies
1
Views
1,488
Miles
Miles
S
Strange noise from HXT motor on scooter
Replies
7
Views
1,672
Jeremy Harris
Jeremy Harris
RemoteContact
RemoteContact's Grinhill inspired bike.
Replies
5
Views
1,528
RemoteContact
RemoteContact
nomad85
Is this ESC suitable for an ebike?
Replies
1
Views
939
recumpence
recumpence
Back
Top