HUB vs BELT - Whats the latest?

Its belts, man. Until @Hummie finishes his Duke Nukem hubs, its belts. Just forget about hubs for now. Direct drives look promising though. Carvon has some good shit happening.

But still belts.

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Belts win for me because I need versatility. I can take my drive train and switch to any motor I like. I can also tune my drive with different ratios. I can switch to any wheel I like, I am not pigeon holed into using a truck with generic geometry. I can tune EVERYTHING!

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Or maybe a swappable stator in a direct drive config. That would work for me too. But who the hell is going to design a swappable stator cartridge? And how would that even work?

yeah. Belts.

until i get my solid lithium boosters finished anyway. Iā€™m working on a new battery pack that vents exploding cells through a thruster nozzle so that when you intentionally trigger thermal runaway it can ignite and nozzle the pressurized gasses out the rear. That way when youā€™re near the end of the race and youā€™ve already over drained your pack anyway you can just hit a button and light up the cells and get that hail mary win.

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The carvon V3 system is modular. The stator can already be swapped with other 63 series SK3 stators with different KVā€™s if they are the same length. The axle is removable as well so a longer stator is possible with a longer axle. Still not as veratile as belts as @Chaka pointed out but I have 83, 90, 97 and 107mm wheels and the difference between the gear ratio between 83 and 107 is huge I can adjust my top speed over 10-15mph range in mush less time than a belt drive can.

@guyguy The 10mile leg was from the begining of the bike path north of thr Santa Monica pier to the end of the bike path south of Venice pier. Speed ranged between 2mph-20mph. Lots of almost stop and go ridong near the piers but no hills. We were all riding together keeping pace with each other so I dont expect riding style played a huge roll in this comparison. As far as me being in my boards sweet spot, I dont think it was at all, my board free revs to 60mph where as @Titoxd10001 board free revs to 34, if anything his board was in a much better position for efficiency in during the relatively low speed riding we were doing.

But why would a 4wd carvon board with a 280lb rider come anywhere near a 2wd belt board with an 80lb weight advantage on our 10mile ride, with stop and go and a decent range of speeds?

Luis is an experienced and knowledgeable builder and rider, we swapped boards towards the end and his boards is super dialed. I highly doubt he running his belts any tighter than necessary to prevent slipping and his numbers were what Id expect for a belt drive dual motor board with a 180-200lb rider.

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If you want a real test, you have to test the same weight and environment. I ride with a Raptor 2 rider every 2 weeks (about the same weight as me 180lbs) and I consistently get better mileage with the exact same battery pack with all our stop & go riding.

Even on my 25R pack with 2Ah less than the Raptor 2, I ended a group ride a couple weeks ago with 71% while he was sitting at 55%.

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yup. All of that is why iā€™m still on belts.

but there is a lot you can do with simply adjusting KV and wheel height. unfortunately its horrifically inconvenient compared to swapping a wheel or wheel pully or both.

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Agreed, but this was the best and closest comparision Ive seen yet and was surprised it leaned in the hubs favor considering the extra weight and motors with my Carvon setup.

I still think the belt drive will shine on hill climbs but really this test was all about providing evidence for a statement I made in Lukes thread.

Our data from yesterday supports this statement.

I dont suspect weight is as much a factor as people make it out to be. I noticed my board died insanely fast during the Enertion Raptor 2 event in SF due to repeated 0 to 100% acceleration races and tests. You should come up to the bay area and join us in one of our group rides :), or perhaps when @evoheyax heals we can do a comparison.

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Evohyax is letting me take his board till the new MOTors come in maybe a week. Iā€™d like to meet you @Jinra or anyone else to do watthours spent w same distance. Iā€™m 155lbs . the track. Twin peaks. Tam. ? Tomorrow? Heā€™s letting me take his helmet w gopro too

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Weā€™re doing a halloween group ride on Saturday, join us for that :slight_smile:

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Agreed, weight would only become a big factor for acceleration and hil climbing and both of those were minimized diring out ride yesterday during the 10mile leg I was refering to.

Getting my board up there is the problem. Id have to mail it lol.

Im in Hawaii for Halloween :wink:

Just ride it up here :joy:

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Thanks for the reply, this is interesting stuff.

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At high speed a heavy guy is likely going to have a bigger frontal area too and thatā€™s everything at speed. Dying to see what efficiency a 6 or 8 wheel street luge could do at 40 or 60mph. Bet it beats every vehicle out there for efficiency. Like a 1\6th the fronal area.

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Lets ride the river trail you mentioned! If I swap to the 83mm flywheels and you swap back to your taller gearing we would be alot closer in effective gearing and it would make for an a more accurate comparison. Im thinking the braking advantage would likely shift in direction of my favor in that case. Im interested to see how much more efficient your geared board would be for climbimg hills. Weā€™d really meed to have similar weight riders for that and need to make sure similar amounts of voltage sag are occuring.

You probably know more than me, so do shoot me down if Iā€™m spewing nonsense, but could you design the removable PU so that it only covers maybe a little more than half the motor can? Iā€™d imagine that would give you slightly better cooling, and even more importantly, you remove excess rotating massā€¦ I mean theoretically, we shouldnā€™t need that large of a contact patch since hub motors donā€™t have enough torque to induce wheel slip.

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sure if you like that. Id rather cover it in rubber though and avoid having to think about bottoming out. a longer tire smoothens out the roughness of the road and can make up for depth. Why worry about excess mass though it seems a small loss.

My 130kv 4wd board breaks traction on all 4 wheels during a hard launch with one of my lighter friends on it and those are mich higher KV and have smaller stators than Hummies motors.

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Rightā€¦ So perhaps you should take a single drive and go on a hill climb versus a dual drive. When you reach the top tell me which has used less power. My point I was trying to make is this is yet again another apples to oranges comparison again and any results found are subject to all variables which greatly affect final finding.

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Iā€™m supposed to write an article on a controversial topic for my English final. Iā€™m definitely choosing this.

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