Kepler Drives are HERE!!

[zap]

Oh, I don't suppose there is really any worth trying to have this motor repaired? I've never cooked a motor before, does it need to be completely re-wound?

Find a rewind shop and get a quote?
Here's one in Portland http://www.advanceelectricmotors.com/???

It depends on the motor but some are a breeze to rewind.

 

[LI-ghtcycle]

Here's an view I have. I can't believe after all the hundreds of pages of threads which I didn't read on the idea of rc motor transportation that nothing has changed on finding the throttle part. People are still using a servo tester? Unbelievable.

He he well, here's the deal, I just assumed between the 2 spare throttles laying around one of them would be a 5k POT, and when I discovered I didn't have one, I went ahead and used the servo tester to just try things out, it's sad really, but what really happened was me not wanting to wait and do it right, I really only used the motor 2 - 3 times on the flat because the servo tester makes for a really scary "throttle" and I never used it at maximum except in no-load.

The acceleration was incredible! I was almost scared to ride it even up to 31 MPH because it got there so fast he he.

Anyone know of a good 1/2 or 1/4 length twist grip throttle that is a 5k POT?

 

[LI-ghtcycle]

As promised, PICS!

 

[oatnet]

Touchdown of the anodized drives!

When my wife walked up to me with the tiny, well- packed box, I didn't know what it was. I did not appreciate how elegantly compact this unit is until I held it - but comparison to the CycleAnalyst and Mirrycle helps convey the idea.

Now I have everything I need... Good thing I spent most of yesterday assembling the mule for this, a real screamer on a S-750 frame.

Thanks Kepler!

-JD

 

[D-Man]

Here's an view I have. I can't believe after all the hundreds of pages of threads which I didn't read on the idea of rc motor transportation that nothing has changed on finding the throttle part. People are still using a servo tester? Unbelievable.

Anyone know of a good 1/2 or 1/4 length twist grip throttle that is a 5k POT?

"recumpence" claims you just saw off the magura till you get the length you need. I know Sram makes different length handlbar grips. I bought some once for the currie ezip throttle.

 

[LI-ghtcycle]

Touchdown of the anodized drives!

When my wife walked up to me with the tiny, well- packed box, I didn't know what it was. I did not appreciate how elegantly compact this unit is until I held it - but comparison to the CycleAnalyst and Mirrycle helps convey the idea.

Now I have everything I need... Good thing I spent most of yesterday assembling the mule for this, a real screamer on a S-750 frame.

Thanks Kepler!

-JD

DROOOOOOOOOOOOOOOOOOOL!!!!

Very nice Oat!! What throttle are you going to use? And is that the 63 - 74 Turnigy 200kv motor? What batteries are you going to use?

Looks great! 8)

 

[LI-ghtcycle]

Here's an view I have. I can't believe after all the hundreds of pages of threads which I didn't read on the idea of rc motor transportation that nothing has changed on finding the throttle part. People are still using a servo tester? Unbelievable.

Anyone know of a good 1/2 or 1/4 length twist grip throttle that is a 5k POT?

"recumpence" claims you just saw off the magura till you get the length you need. I know Sram makes different length handlbar grips. I bought some once for the currie ezip throttle.

Hmm, good to know, are you talking a currie twist throttle? The magura definitely looks good too!

 

[Kepler]

Conspicuous by my absence on this thread. Sorry guys I only just found it

I think this really highlights the need to carefully match kv, motor diameter, and voltage when dealing with this type of drive. Too much need for speed needed around here I really think 35kph at 100% throttle is a good alround target for any RC type friction drives. This will keep the motor turning in its efficiency range under most conditions. Set it up for 50kph plus and the motor is out of its efficiency range and at part throttle way too much of its life. Also you are using serious amps at 50kph plus which also is putting a big strain on a small RC motor.

Here are my suggestions.

If you use a 63mm motor, 200kv @ 5S = good alround performance. (my favourie) 6S = great performance with a little more risk to the motor and ESC
If you use a 48mm motor, 250kv @ 5S = good alround performance. 6S = great performance with a little more risk to the motor and ESC
If you use a 48mm motor, 300kv/320kv @ 5S = great performance with a little more risk to the motor and ESC 6S = very quick but with reduced hill climbing safety

If you are looking to sustain 1500 watts, choose a motor rated at 3000 watts

RC systems have their limitations but we can work around them and enjoy a very reliable system.

 

[oatnet]

Useful guidance on sizing the motor to half of its rated watts. I am jaded to the idea of running 10kw (100v/100a) into "frock" outrunners, which is half of the 20kw Doc has "rated" :lol: the 9c at, I should be sensitive to the 3kw "rating" on the RC motors. Note - I am assuming the chinese rating is how many watts they were pumping in the moment before it failed. :lol:

Set it up for 50kph plus and the motor is out of its efficiency range and at part throttle way too much of its life.

If I set up an ebike for a mere 50kph (31mph) it will be pegged at full throttle all the time and I'll be crying for a little more. I used to ride at 45mph. After an accident I managed to ride my bikes down at 20mph for a while, but once I started riding my 100kmh Vectrix, my natural-feeling ebike speed has crept back up to 35mph.

I really think 35kph at 100% throttle is a good alround target for any RC type friction drives. This will keep the motor turning in its efficiency range under most conditions.

35kph top speed (21mph) is way way way too painfully slow to be of any use for me and I suspect many folks here, so expect a lot of tinkering. 8) Are you saying you think this is the limit of the technology to balance low speed torque and high speed performance, or that you are most comfortable at 21mph? I am already picturing a "Kepler Array", with a super low KV motor for low speeds, a higher KV motor for higher speeds, and switch to move throttle wiper signal between the ESCs...

Maybe it is because I am an ebike guy not an RC guy, but I personally find referring to the voltage as 5s/6s is distracting, I will be using LiFePO4 which has a different cell voltage and sag characteristics. My smallest packs are 8s LiFe which AFAIK has equivalent voltage to 6.0/6.5s LiPo when under a discharge load. My garage is integral to my house, so to me the 25% weight penalty for LiFe is worth offsetting even the slightest risk of fire from safety lipo, or the hassle of removing them from the bike to charge them safely elsewhere.

Also a tip from the instructions, if you are building with one of the Turnigy 63-74 motors that Kepler is using, you will need to purchase (4) M4 x 20mm screws to bolt the motor base to the left swingarm. I'm off to buy a set now.

-JD

 

[LI-ghtcycle]

Eureka!! I believe I have found my holy grail!!

HXT 63-74 200kv Brushless Outrunner (Eq:5240)

http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=3890

10mm Shaft-

200kv rating-

63mm x 92mm size-

914 grams of heat soaking copper-

10 - 36V voltage range (3 - 8S) (I will be running just 6S this time (22V) , I promise to behave! )

I don't see an amp rating or wattage rating listed, but several people are running this motor with their planes at 8 - 10S (30 - 36V)

this bad boy has TONS of copper, will run at 3 - 8S (6.7V - 29.6V) and weighs more and is 20MM longer than the acclaimed Turnigy TGY AerodriveXp SK Series 63-74 170Kv / 3250W and has much better reviews, no "the windings were crap, the magnets fell off" stories in the reviews, the worst I saw anyone say about it was that it was heavier than claimed.

It's got such a WIDE range of voltage it will run at, and best of all, it's still only $60!

I can't see any reason not to run this motor, please someone with more experience let me know if I am missing some fatal flaw, or I will be ordering this guy today!

Measuring my Kepler Drive the worst I can see is that I might need to have a slightly longer pivot shaft, but I believe it should squeeze in there. If not, I can get a shaft here locally.

I would also think that in the future this would also possibly be a great choice for racing i.e. 8S+ for Death Race, E-Bike World Challenge etc.! 8)

 

[Kepler]

Useful guidance on sizing the motor to half of its rated watts. I am jaded to the idea of running 10kw (100v/100a) into "frock" outrunners, which is half of the 20kw Doc has "rated" :lol: the 9c at, I should be sensitive to the 3kw "rating" on the RC motors. Note - I am assuming the chinese rating is how many watts they were pumping in the moment before it failed. :lol:

Set it up for 50kph plus and the motor is out of its efficiency range and at part throttle way too much of its life.

If I set up an ebike for a mere 50kph (31mph) it will be pegged at full throttle all the time and I'll be crying for a little more. I used to ride at 45mph. After an accident I managed to ride my bikes down at 20mph for a while, but once I started riding my 100kmh Vectrix, my natural-feeling ebike speed has crept back up to 35mph.

I really think 35kph at 100% throttle is a good alround target for any RC type friction drives. This will keep the motor turning in its efficiency range under most conditions.

35kph top speed (21mph) is way way way too painfully slow to be of any use for me and I suspect many folks here, so expect a lot of tinkering. 8) Are you saying you think this is the limit of the technology to balance low speed torque and high speed performance, or that you are most comfortable at 21mph? I am already picturing a "Kepler Array", with a super low KV motor for low speeds, a higher KV motor for higher speeds, and switch to move throttle wiper signal between the ESCs...



Maybe it is because I am an ebike guy not an RC guy, but I personally find referring to the voltage as 5s/6s is distracting, I will be using LiFePO4 which has a different cell voltage and sag characteristics. My smallest packs are 8s LiFe which AFAIK has equivalent voltage to 6.0/6.5s LiPo when under a discharge load. My garage is integral to my house, so to me the 25% weight penalty for LiFe is worth offsetting even the slightest risk of fire from safety lipo, or the hassle of removing them from the bike to charge them safely elsewhere.

Also a tip from the instructions, if you are building with one of the Turnigy 63-74 motors that Kepler is using, you will need to purchase (4) M4 x 20mm screws to bolt the motor base to the left swingarm. I'm off to buy a set now.

-JD

I suggest 35kph because its a pace that is above what most non assisted bikes travel at unless they are high end road bikes and its a speed that a normal bike is still designed for. Also, with an RC system, the motor and ESC are in a much better operational range when traveling at hill climbing speed. Lots of people like to push it much harder then that and if thats the case, they need to make a motor and battery selection based on the speed they are looking for. The 63-74 on 5S (18.5V) is even too fast for some which is quite understandable.

In relation to instructons, thanks for the tip. The instructions have now been amended.

 

[Kepler]

Eureka!! I believe I have found my holy grail!!

HXT 63-74 200kv Brushless Outrunner (Eq:5240)

http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=3890

10mm Shaft-

200kv rating-

63mm x 92mm size-

914 grams of heat soaking copper-

10 - 36V voltage range (3 - 8S) (I will be running just 6S this time (22V) , I promise to behave! )

I don't see an amp rating or wattage rating listed, but several people are running this motor with their planes at 8 - 10S (30 - 36V)

this bad boy has TONS of copper, will run at 3 - 8S (6.7V - 29.6V) and weighs more and is 20MM longer than the acclaimed Turnigy TGY AerodriveXp SK Series 63-74 170Kv / 3250W and has much better reviews, no "the windings were crap, the magnets fell off" stories in the reviews, the worst I saw anyone say about it was that it was heavier than claimed.

It's got such a WIDE range of voltage it will run at, and best of all, it's still only $60!

I can't see any reason not to run this motor, please someone with more experience let me know if I am missing some fatal flaw, or I will be ordering this guy today!

Measuring my Kepler Drive the worst I can see is that I might need to have a slightly longer pivot shaft, but I believe it should squeeze in there. If not, I can get a shaft here locally.

I would also think that in the future this would also possibly be a great choice for racing i.e. 8S+ for Death Race, E-Bike World Challenge etc.! 8)

The pivot shaft length is designed to handle that motor so its straight in. Dont forget to get some m4 x 20mm bolts

 

[oatnet]

Eureka!! I believe I have found my holy grail!!

I bought that motor, from the 'suggested motors' link on the first page of the kepler sale thread because that is the one Kepler has been testing with...

 

[Hillhater]

Eureka!! I believe I have found my holy grail!!

HXT 63-74 200kv Brushless Outrunner (Eq:5240)

http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=3890

10mm Shaft-

200kv rating-

63mm x 92mm size-

914 grams of heat soaking copper-

10 - 36V voltage range (3 - 8S) (I will be running just 6S this time (22V) , I promise to behave! )
I can't see any reason not to run this motor, please someone with more experience let me know if I am missing some fatal flaw, or I will be ordering this guy today!

Measuring my Kepler Drive the worst I can see is that I might need to have a slightly longer pivot shaft, but I believe it should squeeze in there. If not, I can get a shaft here locally.

I would also think that in the future this would also possibly be a great choice for racing i.e. 8S+ for Death Race, E-Bike World Challenge etc.! 8)

Li' ... just for info, another option may be the Turnigy 63-54, 250kv motor.
It has all the same specs as the 63-74, except for the slightly higher KV rating but it is 20 mm shorter for a more compact installation .

Kepler, ( or anyone ?)
do any of the Turnigy 50 Dia motors have skirt bearings ?? ( and low KV).. or are the choices limited to Hyperion in that size range ?

Also, i am bench testing the Turnigy 63-54 with the turnigy K force 100a ESC on 18.5 v .
It runs fine until i load it up when i get a mid speed "rattle" from the motor.
EDIT :- re-checking i would say this is a "screech" sound , and the motor actually stops driving until i throttle back and start again.
I am sure this is an electrical effect, but curious to know what the cause and cure is ?...
Is this the infamous "sync" problem ?... ESC timing / programming maybe ??

Incidentally, no load max rpm when driving on a test bike wheel is 4260 rpm or 410 rpm of the 26" wheel. Equivalent to 31 mph (50 kph)
When run in real life on the road i suspect this would be more like 40 kph max.

 

[zibbby]

I just have take apart the Turnigy 63-54, 250kv motor . It has skirt bearing.

 

[LI-ghtcycle]

Eureka!! I believe I have found my holy grail!!

I bought that motor, from the 'suggested motors' link on the first page of the kepler sale thread because that is the one Kepler has been testing with...

Good deal, I somehow missed that thread in the midst of my searching for a seriously fast motor! :lol:

I also wanted to point out something rather obvious, but I forgot to do it, so here it is:

Just because the Kepler drive is light, doesn't mean you won't need a high quality double wall rim or the like if your going to push the limits! I didn't taco my wheel, but I did have a hard time keeping it true after spinning it no-load several times at 61 MPH! :lol:

I then was trying to compensate by tightening up the spokes, only to realize too late that I had the spokes way, way, WAY too tight, to the point that I'm going to have to cut several spokes just to start over again, they are so tight I can't loosen them now with-out twisting the ends off the spoke nipples!! :wink:

 

[oatnet]

Just because the Kepler drive is light, doesn't mean you won't need a high quality double wall rim or the like if your going to push the limits! I didn't taco my wheel, but I did have a hard time keeping it true after spinning it no-load several times at 61 MPH

Ebikes are usually serve harder duty, so yep quality rims/spokes are always a good idea. However, the pressure of the motor against tire should be far less than my weight presses it against the pavement. I'd suspect some spoke stretching from a new wheel or the centripital force at high RPM, but not the drive.

I'm using 38mm Alex DX-32 rims and Maxxis Hookworms for a very large contact patch with the motor, which should distribute the load as best as possible, and provide the best contact with the drive.

-JD

PS I just posted an assembly guide for the Kepler Drive here:
http://endless-sphere.com/forums/viewtopic.php?f=28&t=21309#p310663

 

[LI-ghtcycle]

Just because the Kepler drive is light, doesn't mean you won't need a high quality double wall rim or the like if your going to push the limits! I didn't taco my wheel, but I did have a hard time keeping it true after spinning it no-load several times at 61 MPH

Ebikes are usually serve harder duty, so yep quality rims/spokes are always a good idea. However, the pressure of the motor against tire should be far less than my weight presses it against the pavement. I'd suspect some spoke stretching from a new wheel or the centripital force at high RPM, but not the drive.

I'm using 38mm Alex DX-32 rims and Maxxis Hookworms for a very large contact patch with the motor, which should distribute the load as best as possible, and provide the best contact with the drive.

-JD

PS I just posted an assembly guide for the Kepler Drive here:
http://endless-sphere.com/forums/viewtopic.php?f=28&t=21309#p310663

Yeah, I'm pretty sure it was me spinning the wheel so fast and having it off slightly at that speed (61 MPH!!) makes for a wobble prone wheel with out a strong wheel/spokes.

I'd love to take something running 8S on a racetrack!

 

[Uncle D]

Just an FYI, the Turnigy 63-74 200kv is the same motor as the HXT pictured here in this thread. I received mine. While I thought it was a decent sized motor, most of the size is due to the skirt bearing. Still the motor looks to be in good shape. Lots of epoxy between magnets, spins freely and clean sounding, and windings look decent.

 

[LI-ghtcycle]

Yeah, I believe you're right, for some reason they have it miss-labeled as HXT, it says Turnigy right on mine, looks just like the one you have pictured.

I now have a second one too as back-up since it's not something I can just buy from a local hobby shop.

I have been so focused on my fairing/cargo pods that I haven't up-dated here.

I have my newly replaced Castle Phoenix ICE 100 ESC and I have a cheapo Ebay ESC as back-up, but I doubt I will ever need it.

Soon as I decide the design for my front fairing and have it equipped with my MS headlight, I will be able to focus on the electrics more.

 

[LI-ghtcycle]

Well, no pix tonight, but I have the bike 80% there! Shooting for under 40lbs (should be closer to 35 I think) but I will have that info soon, ditched the fairing on this bike (Muddy Fox hybrid) I will attach it to my Trek 830.

Pix to come soon!

 

[LI-ghtcycle]

Well, slowly I am posting pix, sorry to take so long, here's the finished product!

Best part is it's only 41 lbs with 18AH's of LiPo! I'm sure it could have been a lot closer to 35, but I love my gizmos!

Not to mention all the extra wire running the Watt Meter to the bars, comfort bars, etc. , etc. :wink:

 

[neptronix]

41lbs.. damn, that's nice. Perhaps you set a record for lightest eBike

 

[LI-ghtcycle]

Thanks! I don't think it's the record however, I think Recumpence's BMX bike is only 35lbs, but again, this is a road bike, so maybe I might have one of the lighter Road/Hybrid bikes!

 

[neptronix]

BMX doesn't count.. those aren't real bikes.

*dons flame-proof suit*