Commencal Supreme Custom Mid-Drive Build

Leeleeducati said:
Where did 9Nm or 10-12Nm come from?
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Hi Lee,
it gives 10Nm on the link that you posted: http://www.bearingscanada.com/NSS12-One-Way-12x32x10-Bearing-Support-Required-p/nss12-one-way-123210-requi.htm

Different companies rate in different ways but the nominal rating for a CSK12 is usually between 7.5Nm and 12Nm. The peak rating being around double that.
 
Stieber give a TKN of 13Nm for the NSS 12: http://www.altraliterature.com/pdfs/P-7426-SC-A4_Built-In-Freewheels.pdf

The fact that they're roller ramp type rather than sprag type seems to preclude an integral bearing within the 62 bearing series envelope. The actual difference in torque capacity over the CSK/CKK type is a factor of 1.4. Stieber give a TKN of 9.3Nm for the CSK/CKK 12 and a TKN of 13 Nm for the NA/NSS 12.

CSK/CKK page: http://www.altraliterature.com/pdfs/P-7426-SC-A4_CSK.pdf
 
Miles said:
I think you need to start again with the whole freewheel assembly.
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Miles said:
Alien give a maximum torque of 9.5 Nm for their 80100 motor.

So, that would be 95 Nm after the 10:1 reduction.
Click to expand...

yes, probably need to recalculate and reproject all the reduction ratio, starting from the motor costants.

perhaps could be useful to complete the following list:

MOTOR: 80-100 reterminated in wye
Constants?


MOTOR TO APEX GEARBOX 14:11?
APEX GEARBOX 1:10
APEX/DALTON TO JACKSHAFT MOTOR INPUT: 24:15?
JACKSHAFT COMMON OUTPUT: 21t?
FREEHUB CASSETTE CLUSTER : (standard? custom?)
JACKSHAFT PEDAL INPUT (has the same bearing?) : 11t?
CRANK PEDAL SPROCKET: 16t?

If those numbers are not exact, I think they are very close, so with an hypothetical slow 120kv motor we have:

120rpm*48 =>5760rpm*1.272*0.1*1.6=>1172rpm (at the jackshaft)

And 9.5 Nm*11/14*10*15/24=>46 Nm

And with 100 of cadence we have

100rpm (pedal)*1.45=> 145rpm (at the same jackshaft, an order of magnitude is missing there.... :? )

Than we have a 21/11-36 or whatever....in the motor figures that's a 500 to 1500+ rpm spinning wheel :shock: ......

Seems there's even the same one way bearing at the JShaft pedal input....It should sustain the human torque * 0.68 when loaded?.....again it's undersized I think
 
then after the bads, I would focus on the greats....

The frame was a top frame in terms of possible abuse, and the welds seems well performed. the Alloy 7005 is one of the best to be welded without exotic treats.
The Jackshaft pivot is a beautiful option.
The APex seems a cool gearbox, but not in the right place, you could consider selling it for funds.
The dalton Clutch seems bigger than usual but should be useful in some way
The Motor is an X factor, For me the efforts and results on the frame screams for a better Quality motor, But It should be good.
The ESC is the best you could have and yet shunted and mated with a CA
Batteries and electronics are good too

I would reproject the jackshaft with standard ratcheting freewhels and adapters from staton inc or similar they have them for almost any bore size, keyed, with setscrews or even blank.

Sounds crazy, but if you reverse all the sprockets (so 10*1.7*1.6 = 27.5/1) you got an acceptable speed at the jackshaft to meet the pedal input and go to the wheel at a typical ground vehicle speed instead of a deep space spacecraft velocity.....

A low profile approach, but maybe smart, could be to leave the motor train questions for the moment and see if the pedal chain works acceptably, as for the reprojected pivot point, the bearings, ecc. so you have not surprises later, considering that you will need time, money and efforts to get all working.
You should consider that as a challenge. the bike is awesome and unique, you must get her running....
 
Would be glad (and I believe it's the same for many other members) to help sorting out with something good, Steven.

Please check the no load speed and amps of your motor and post them here first, If you have not them already, than you need a motor speedometer, but you have also the CA (perfect for the no load amps but with some effort the CA spedometer could be used for rpms too) and the castle software to play with for rpms too, plus you have an outrunner that should be easier to be measured.

Than, as said, check the bike with the pedal transmission only, for how the modded pivot works. you actually have the equivalent of a 30t chainring (21* 16/11) a 18t as freewheel chainring should be better.

If the pivot drive works great, man, you have many amazing options to go ahead....trust me.
 
Quite disappointed that i'm out $100 on this bearing, because someone told me this bearing has been proven to work for this application.

Does anyone else know of a bearing that will in fact work?

My reduction:

1 - 13t
2 - 11t
3 - 17t
4 - 15t
5 - 19t
6 - set of gears + derailleur
7 - 10t
8 - 17t

Screen_Shot2014_06_18at175139_zps7a8f0737.png


There is a lot of continued support on here, and I thank you all for that. I took a brief look at all of this help and noticed there are some other questions that need to answer. I will be able to follow up shortly on these other questions I need to answer to get the help everyone is so graciously providing such as no load speed and amps, rpm etc.

IMG_20160605_184401.jpg


IMG_20160605_184319.jpg
 
I make that a reduction of 7.47:1

So, if we assume a maximum torque from the motor of 9.5Nm and multiply that by 7.47, we get 71 Nm.

I'd say you need something with a nominal torque rating (TKN) of 40Nm for the current set up but, as we said the current set up doesn't make much sense....
 
for the 80-100 specs that could be useful: https://endless-sphere.com/forums/viewtopic.php?f=30&t=20618
But Miles has probably more to add. Seems it was a Delta motor reterminated in wye. So probably from an 8t delta (132kv) to 8t wye (76 kv).

Ah, If nothing has changed, it seems a 14t to me...http://s601.photobucket.com/user/03...90F-697-0000004AD9A6352F_zpsc9620ab4.jpg.html

at the crancks 17-10 seems better than the 16/11 I supposed, so, you have a 35t equivalent, and run the jackshaft @170 by pedaling at @100

EDIT

Recalculating with new ratios and a possible 76kv motor:

48*76=>3648rpm/7.47=>488rpm @Jackshaft (and this makes much more sense)

You would clear this gap (170-488) but not all probably. So, IMHO, you need something like 300-350 at the jackshaft pedal input, that means a 30-35t chainring instead of your actual 17.

but with those figures (76kv and 7.47 ratio) at least the wheel speed will be human (probably 50-55kph top speed if driven 1/1 to a 19t cassette cog on a 26" tire)
 
calc looks good to me. i'd like to get rid of that apex gearbox though. it's just dead weight. swap number 2 for a 36t and number 4 for a 46t. then you have 13/35 and 17/46 and end up with the same total 7.5 ratio

or go for a 13/35 combo for number 3 and 4 to get it smaller

number 7 is too small with 10t. you will fell polygon effect when pedaling this very short chain. swap it for a 13t freewheel sprocket, then you wont feel that polygon ripple anymore.
 
Sad to hear that. I understand the frustration of spending your enthusiasm and money for one-way bearings and a new jackshaft.
But in fact you probably need nothing more than to buy solid freewheel adapters from staton inc (http://www.staton-inc.com/store/index.php?p=product&id=1864 , for13t FW and http://www.staton-inc.com/store/index.php?p=product&id=1863, for 15t+ FW) and let the shop that made the new shaft for you, to bore these solid adapters and provide them the right key groove /set-screw fix for your shaft...shouldn't be that hard.

When you have a working jackshaft with ratcheting freewheels able to withstand the loads involved, it's only a question of sprocket's ratio, space for them, and speed of your motor (battery voltage*kv of the motor).

To get the kv of your motor, assuming that the actual one-way bearing transfers all the rpms when the bike is lifted without any slip, as seems from your video, you may simply use the CA speedometer as is intended for, on the rear wheel, and get a no load wheel speed.
This value (kph or mph), after some conversion and calc using ratio and wheel circumference (you could set an arbitrary useful value on the CA to simplify calcs here and play with magnet count as well) will return a -rpm per volt- value close to the theoretical motor kv, and even more useful because includes the entire drive-train losses (only external loads excluded) so a bit more "real".
Another method, using any precision rotating tool (I.E. the lathe of your local shop :wink: ), is to reverse measure the motor velocity constant by applying a known rpm input at the motor shaft -in the motor speed range, of course- and measure the voltage output at the phases....

Hope you'll find again the time and the enthusiasm to get this frame flaming on the trails, you both deserve that :) .
 
I hope you find back your enthusiasm and some free weekends to complete this bike.
 
Steven,
I anticipated the motor smoking. A couple of the stages have gear ratio increase instead of gear reduction. The point of using the gears is to reduce the motor rpm and convert to torque. By doing the reverse you're asking the motor to supply more torque per rpm which burnt it up.

Anyone, please comment on this or Steven will give up if he doesn't correct the drive train issue.
 
Mongo1 said:
Steven,
I anticipated the motor smoking. A couple of the stages have gear ratio increase instead of gear reduction. The point of using the gears is to reduce the motor rpm and convert to torque. By doing the reverse you're asking the motor to supply more torque per rpm which burnt it up.

Anyone, please comment on this or Steven will give up if he doesn't correct the drive train issue.
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Not exactly, It is the total reduction between the source (motor) and the load that count and here is anyway 7.5:1 so an effective reduction of rpm and increase in torque.

Here is not a question of reduction amount (7.5 could be ok in the suspended part of the drive). But mostly on how that reduction is achieved.
Also, a working freewheeling jackshaft is the primary concern IMHO.
Hope to hear again about that build....
 
Hey everyone,

So i'm at that time of year again where I have 2-3 months of less work and school hours so I'd like to get this bike rebuilt.

I blew the motor as mentioned earlier, so I need a new motor.

Someone mentioned the gear box is not ideal and whatever the reason i'm in agreement because i'd love the extra battery room (with the gear box in, all my wiring hangs off the side of the frame because there's no room for it and it's dangerous because some are still stuffed in the frame with the batteries i.e. need to make room in there)

The jackshaft wasn't working with whatever bearing I used to I welded it (as mentioned above) so that should be totally replaced as well. Someone mentioned using a rear hub shaft? I would have to take some measurements but it would be a wicked coincidence if the diameter of the rear swing arm attachment i'm using for jackshaft is the same diameter of a rear axle...

So, here we go. I need a new motor, and jackshaft. Basically redoing the entire reduction system because is was clearly out of wack. I think the controller is still good, and the batteries are definitely still good. Obviously still have the frame and all the goodies like cycle analyst etc.

Any recommendations on what I should order for motor and jackshaft?
 
Glad you haven't abandoned that project.
Buy a straight 12mm steel (or Ti) bar (yes gravity MTB rear axles are 12mm and useful even in length, that's typically over 160mm for the 142-150mm dropout versions, but are usually alloy so not the best choice for this application). It should be cut at the same 141,5 mm the old one was (assuming the 3 chainlines are actually ok) and use standard ratcheting freewheels mounted over Staton inc. adapters. There will be eventually only very minor mods to do.

As motor, I would use nothing but an Astroflight 3220....And there I would probably keep the Apex gearbox, since the astro is sensibly faster (169 Vs 76 rpm per volt of the old one), you may still need it to keep the astro's 7-8k rpms down at usable speed for the jackshaft.
You need than to reach similar speed with pedal cadence, I would say at least 70-80% of the motor input speed if you plan to have useful cranks.....
 
Hey,

Thanks for the info. Could you give me an example of a standard ratcheting freewheel I should use? I've looked at a few and have a hard time understanding how it will function without having a hub to link on, i.e. an axle doesn't have the teeth it needs to have a one way bearing function. I looked at some of the adapters you mentioned and don't see the resemblance between those teeth and the teeth a freewheel uses to hold it on a hub.

Thanks!
 
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