ROCKWHEEL GT16

[Scatcat]

4 hours ago, kasenutty said:

The GT16 is the most exciting and most frightening wheel available today. 

@kasenutty I don't find it very frightening. It's very strong, accelerates like a bat out of hell, and the warning signal could really be louder. The pedals are too small, and the padding on the sides is not as good as I would like. But frightening, no.

[Carlos E Rodriguez]

7 minutes ago, Scatcat said:

Damn! I see they make the same mistake as everybody else, flattening an already to narrow axle...

Why can't they flatten just 5mm less of the axle length, so that the first bit in the pedal assembly closest to the wheel is the full axle diameter without any weakened spots? And preferably flatten it less too, the torsion shouldn't be all that hard to take even if more of the axle thickness is kept.

@陈小杰 This shouldn't happen, either use a bigger axle or take steps not to create weak spots.

Its not a mistake. They need to stop buying bicycle motors and not cut down the shaft diameter to accommodate bicycles.  They could use the same axle if they would just not reduce the diameter on the end but keep the shaft the same thickness all the way.

[meepmeepmayer]

4 hours ago, kasenutty said:

The GT16 is the most exciting and most frightening wheel available today. 

Hihi True, these two things come in pairs unfortunately. At least with EUCs they do. New better model, but new untested (by the customers, naturally, it's not like it's the manufacturers job) model.

[Scatcat]

2 minutes ago, litewave said:

 

OK then, Rockwell GT16 now deleted from my wishlist. 

Well, the axle is 18mm AFAIK before flattening, which makes it pretty normal for 16-18" wheels. And all makers do that: flatten the axles too much. I seems they don't think it through.

[meepmeepmayer]

Just now, Scatcat said:

I seems they don't think it through.

EUC manufacturers not thinking things through?! Shocking news!!! 

[Carlos E Rodriguez]

2 minutes ago, Scatcat said:

Well, the axle is 18mm AFAIK before flattening, which makes it pretty normal for 16-18" wheels. And all makers do that: flatten the axles too much. I seems they don't think it through.

LOL.  Yeah thinking.

[Scatcat]

 Ooops, I forgot it's EUC makers we're talking about. They'd probably stick stuff together with chewing gum and candle wax if they thought it would save some money.

[WaveCut]

20 hours ago, kasenutty said:

The GT16 is the most exciting and most frightening wheel available today. 

Exactly the same story that we saw with Rockwheel GR16.
It was the breakthrough for it's times. And its gone. Just because of quality and safety issues.

[Scatcat]

@陈小杰 A very simple way to alleviate the problem with broken axles, could be to have the flat part of the axle vertical instead of horizontal. Since the shearing forces comes mainly from above and below, having the axle uncompromised in the vertical should be more important than the lateral. For such a change, the only part that need changing is the pedal arm, where the shape of the cut must be turned 90°. That should be a rather trivial change, shouldn't it?

After all, the only reason for flattening the axle is to make it NOT spin in the pedal arms, isn't it? And that should work just as well with the flattening being vertical instead of horizontal, shouldn't it?

[陈小杰]

After the second batch, the large shaft has been replaced.  The first batch of 300PCS is small.

[陈小杰]

[lizardmech]

When is the 92V version released?

[Scatcat]

46 minutes ago, 陈小杰 said:

That is very good.

I do hope my own isn't part of that first batch... but I see no tendency of the axle to bend so far.

[Hunka Hunka Burning Love]

Considering that the axle needs to be hollowed out to have wiring come out of one side plus it requires a flat side or two, wouldn't it make life a lot better to just have a larger bearing and axle diameter?  That way you can pass through heavier gauge wiring easier, flatten sides all you want and eliminate the possibility of axle breakage completely?  Sure the motor covers would need to be able to accommodate the larger bearings and thicker axles would be needed, but in the end a little over-engineering can avoid problems from ever occurring.  If an axle breaks once, it likely will happen again.  Why not eliminate that possibility with some simple changes?  How much can a slightly larger bearing and axle cost in the large scheme of things?

If you ask someone do you mind paying a little extra for an axle that can never break, or do you want a wheel with an axle that might not break if you're lucky, which one do you think they would opt for after riding somewhere for 30 kms in the middle of nowhere?

[litewave]

1 hour ago, Hunka Hunka Burning Love said:

Considering that the axle needs to be hollowed out to have wiring come out of one side plus it requires a flat side or two, wouldn't it make life a lot better to just have a larger bearing and axle diameter?  That way you can pass through heavier gauge wiring easier, flatten sides all you want and eliminate the possibility of axle breakage completely?  Sure the motor covers would need to be able to accommodate the larger bearings and thicker axles would be needed, but in the end a little over-engineering can avoid problems from ever occurring.  If an axle breaks once, it likely will happen again.  Why not eliminate that possibility with some simple changes?  How much can a slightly larger bearing and axle cost in the large scheme of things?

If you ask someone do you mind paying a little extra for an axle that can never break, or do you want a wheel with an axle that might not break if you're lucky, which one do you think they would opt for after riding somewhere for 30 kms in the middle of nowhere?

Well said, excellent post. 

Triple up-vote!

[Carlos E Rodriguez]

5 hours ago, 陈小杰 said:

Interesting!  Why do you need to shave off the shaft!  I think you should keep it round. And posibly just add a key way or key pin. If you can find a way to lock the pedal arm to the shaft and not shave any material. It will be the best. 

Edited June 16, 2017 by Carlos E Rodriguez

[Hunka Hunka Burning Love]

 I guess after hearing about the odd KS14 axle breakage that shows up every now and then it just makes me wonder why not up the standards?  It's sort of like hearing bicycle pedals breaking off during usage.  It doesn't happen that commonly because the thickness of the support is wide enough to handle stresses.  People go mountain biking and jump off hills landing with quite a lot of force on the pedals.  Why be on the edge when a few extra millimetres can make a huge difference?  I know these wheels are likely originally designed for average Asian weight riders, but a simple change like that can rid the problem from ever happening again.

I believe with cars, the CV joint is connected to the transmission using a spline joint.  With cars they are able to exert a lot of torque without any issues on the joint breaking free.  You can see that the circumferential grooves do not compromise the thickness of the shaft.  But keeping things simple, a larger diameter axle and bearing to match would likely be the last we hear of axles ever breaking if this change were to be implemented.

 

Edited June 16, 2017 by Hunka Hunka Burning Love

[陈小杰]

I designed a motor that has been patented in China, which will change the design of EUC.

 

[陈小杰]

12 inch, power 1200W, very suitable for mountain off-road EUC. Also use the 247 package MOS, the controller will be installed in the middle of the motor.

[陈小杰]

[PriestHood]

56 minutes ago, 陈小杰 said:

I designed a motor that has been patented in China, which will change the design of EUC.

 

Looks like an 18 or 20" tire.

Edited June 17, 2017 by PriestHood
Mispell

[lizardmech]

Someone did this already.

[陈小杰]

My characteristic is that the pedal is mounted directly on the motor.

[lizardmech]

11 minutes ago, 陈小杰 said:

My characteristic is that the pedal is mounted directly on the motor.

Have you ever considered axial flux motors? Custom design can be made much cheaper than radial flux motor because stator design does not require custom laminations to be stamped

.

[Hunka Hunka Burning Love]

Those open axle motors look super heavy duty!  Nice.  What sort of speed / torque can they reach?  With the larger bearing support friction, is it still able to achieve decent speeds?  Plus how is the extra weight of the motor affecting range per charge?  Are there plans to release it in a commercial product?  I wonder if @EUC Extreme would be interested.

Edited June 17, 2017 by Hunka Hunka Burning Love