kh/hr to erpm
speed_in_kmph= pi*D_in_mm*rpm*60/1000000 = pi*D_in_mm*(erpm/pole_pairs)*60/1000000
erpm= speed_in_kmph*pole_pairs*1000000/(60*pi*D_in_mm)
erpm = 7*10*1000000/(60*pi*110) = 3376
BTW, do you have metr pro/nrf51_vesc on your board? If so give the vesc_tool app a try. Sooo convenient.
Dang it. It’s erpm not rpm. Radius is 55 for my 110mm.
Mad DD poles = 28 poles
7km/hr * 28poles * 1000000 = 19600000
19600000 / 60 * pi * 110
19600000 / 14124 = 1388erpm
Is this correct?
28 magnets means 14 magnetic pole pairs. Basically erpm means how many times a point on stator experiences a complete cycle of north-south-north pole per minute. so erpm = pole_pair*rpm.
7*14*1000000/(60*pi*110)=4726
28 magnets, 24 poles.
@pookybear
28 magnets(Or 14 magnetic pole pairs) on the rotor…
24 stator poles. Stator poles don’t count in our analysis.
so this still holds.
7*14*1000000/(60*pi*110)=4726
Mine arrived today!
All looks good other than the screws look to have the wrong size heads -
I will have another look at them later when I get home
Sometimes on these they only come finger-tight.
They have used the wrong screws, here is no counter sink in the adaptor. When I went to remove the screws and found that 2 of them have already been stripped with a hex tool and I’m going to need to dremmel them.
I don’t have my calipers on me, does anyone know the size of the screws so I can order some replacements?
Bummer. Hate to see that. When my board comes later today I’ll see if my screws are proper and I’ll measure for you.
I have the exact same. They have done it to create a flatter profile so that the bolts don’t rub against the wheels.
In order to even attempt opening them you have to heat it a lot by a hot air gun or a small torch.
Screws are m3 if I remember correctly.
BTW, why did you have to remove the screws at all?
I dont have any wheels with kegle cores. I have original ABEC 97mm reflys and 90mm clones. A friend 3D printed me some clone adaptors to use.
Gotcha. So, yeah. Heat each screw individually using the small blow torch available at the corner stores. And only then attempt to open it. Otherwise they will strip, which is what happened to you. You could also use a grip pliers/locking pliers to remove them once heated up.
Something like this
EAGLE TORCH POCKET TORCH GUN ASSORTED COLORS 4" PACK OF 1 https://www.amazon.com/dp/B01M5BWQ5F/ref=cm_sw_r_cp_apa_i_fAJgDbGQWPSM9
Thanks for the info.
The 2 screws I can’t remove were already stripped. I poped my hex in there and it just rotated around 
I’ll get some more ordered this evening
Wow, there are so many variants.
I wanted the ABEC adaptors and Kenna said they were not available.
Adaptors is the least of my issues though. I managed to get the 2 rogue bolts out and then went to install the adaptors and found that the adaptor does not fit. Looks like the printed part is a little too small. Still not really a problem compared to this
Yep, the threaded part is 7.8mm and the actual shaft is 8.2mm.
Let’s see how good Kenna is resolving problems.
This sucks. Torqueboards even had the same problem and had asked people to use sandpaper to reduce their diameter a bit.
Just got back the first 15.7 mile ride. Slapped my old Abec 107mm wheels and went. I only have 4 lights for battery indication but it’s between 50-75%, blinking third light. Compared to my, now sold carbon GT, the battery has more range. The punch from 0-12mph-ish is weaker as well and the brakes from 12-0mph. But the curves are much smoother. Top speed is higher than the CGT as well.
