That was a great presentation wasn't it
...when Justin was talking about somebody oil cooling and "water" cooling a MAC, he was talking about me. He helped me a lot as far as figuring out how to plan my experiments. IMO oil and water cooling can work for a MAC/GMAC but they both have unique challenges. After having done it, IMO it is a lot easier to just limit your speed and/or run a smaller diameter wheel/tire so you don't overheat the MAC.
Here is a link to some of the water cooling and clutch info with pics: https://endless-sphere.com/forums/viewtopic.php?t=104226
and
Here is a link to the Low Viscosity ATF experiments...my experimental data is on page 77 of the thread: https://endless-sphere.com/forums/viewtopic.php?t=48753&start=1900
IMO the guy that built a custom shroud to pump air through his MAC would be a real good option...no chance of leaking any fluid. Air cooling doesn't work as good as liquid cooling but it is a lot simpler. If I could get one of his shrouds I would run it and use a K&N filter to remove any debris from the incoming air. His info and pics are towards the top of page 77 of the same thread.
donn....Thank You but I have the safety gear, just foolishly didn't put it on since I was only going to ride about a 1/2 mile. ATGATT (All the Gear All the Time) would have been the smart thing to do but noooo and I paid for it.
markz...check with "Balmorhea" (that is the name he uses on this forum), he has a source for spokes that are 13/14 gauge and you can get them custom made to whatever length you need and they are fairly inexpensive. Nice thing about them necking down is you can get better tension in the spokes which makes a wheel that doesn't tend to loosen up over time. Probably not a good idea to run different spokes in a perfect world but "different" would be better than a missing spoke :lol: . Read somewhere that one broken spoke is OK, two broken spokes isn't good but still OK, three broken spokes and you should get it fixed
. I weigh about 210 lbs with all my gear on and I beat the crap out of my bikes (all hardtails)...I run 13 gauge Sapin spokes with the nipples that have a hemispherical contact surface against the rim (I think)...all from EM3ev and they seem to hold up nicely. Of course I re-tighten them after riding for a little while when the wheel is new. I use the tone they make after tapping them with a wrench to get tension fairly equal as opposed to a fancy tension gauge which would be better if I wasn't soo "thrify" :lol: . You probably already know all of this...but maybe a newbie reading it will learn something :wink: .
NEW PROJECT #1...after I get these stitches out :lol: . Just received my 8T MAC from EM3ev and I plan to run it with a 12 FET (IRFB3077 FETs) controller programmed for 50A battery and 140A phase current. Along with a 14s6p (25r cells) battery. The controller comes programmed to the max that EM3ev recommends which is 40A/112A.
QUESTION...has anybody run a 12 FET controller above 40A/112A and if yes, how did it work?
Project #2...Try my 12T MAC on 72v. If anybody has tried a 12T MAC on 72v, I'd sure like to hear your results. From what I have been able to find, the core losses start to stack up a little too much if you spin a MAC over about 400 rpms but that is the older MAC with thicker laminations...haven't been able to find any data on the newer MAC with 0.27mm laminations (decreases eddy current losses) that might even use higher quality steel (decrease hysteresis losses).
Thanks everyone
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but the BBSHD would have nearly double the wheel torque in low gear, assuming both were paired with a Phaserunner (RIP cassettes). Justin mentioned yesterday in his presentation that they're looking at oil/liquid cooling for the GMAC since it's properly sealed, so a 2000W+ MAC might be possible (without overheating) after all?
