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BrianG · 07.07.2009, 04:04 PM

As to your radio, yes it's possible, and yes, it will be a moot point to check without an ESC (unless you have another MM/MMM just to try it). Definitely something to look into once you get a new/repaired ESC.

Yes, the 1515 is a very powerful motor, but the ESC controls the amount of brake force in proportion to the radio brake input. What you describe sounds like it was all or nothing, and that's not how it should act, no matter what size motor you have. Again, I suspect a radio/ESC calibration issue, or the throttle channel was reversed in the radio. It's gotta be one or the other unless the MMM brains circuit was totally goofy (and I suspect you'd have had other issues if that was the case).

Yes, the 1/8 scale diffs do make a difference. IIRC, the stock diff ratio is ~2.6:1 or 2.8:1, and the hybrids are either 3.3:1 or 4.3:1 depending on if you got the buggy or truggy version. So yes, it was "geared down" just from the diffs. But, a large tire can add substantial amount of speed, more than you'd think. Go into my calc (link in the sig) and enter all your data and see what the speed is.

At any rate, if speeds were in the 35-45mph ballpark, you're fine gearing-wise. Something just happened to the ESC to make it go poof, and we'll probably never know. I would look over the driveline (particularly the center area) to make sure there aren't any rocks or anything that might cause it to jam; just because it rolls freely on the bench doesn't mean it will when running because a rock or something may be in a position where it makes occasional contact enough to jam. I frequently get this on my CRT.5; a rock will jam between the axle and a-arm and I'll suddenly be doing donuts. Since the ERBE doesn't have a center diff, I would look at the center drive line as that is the only area that will actually stall the motor (the individual axles would diff out).

	(#41)
BrianG RC-Monster Admin Offline Posts: 14,609 Join Date: Nov 2005 Location: Des Moines, IA	07.07.2009, 04:04 PM As to your radio, yes it's possible, and yes, it will be a moot point to check without an ESC (unless you have another MM/MMM just to try it). Definitely something to look into once you get a new/repaired ESC. Yes, the 1515 is a very powerful motor, but the ESC controls the amount of brake force in proportion to the radio brake input. What you describe sounds like it was all or nothing, and that's not how it should act, no matter what size motor you have. Again, I suspect a radio/ESC calibration issue, or the throttle channel was reversed in the radio. It's gotta be one or the other unless the MMM brains circuit was totally goofy (and I suspect you'd have had other issues if that was the case). Yes, the 1/8 scale diffs do make a difference. IIRC, the stock diff ratio is ~2.6:1 or 2.8:1, and the hybrids are either 3.3:1 or 4.3:1 depending on if you got the buggy or truggy version. So yes, it was "geared down" just from the diffs. But, a large tire can add substantial amount of speed, more than you'd think. Go into my calc (link in the sig) and enter all your data and see what the speed is. At any rate, if speeds were in the 35-45mph ballpark, you're fine gearing-wise. Something just happened to the ESC to make it go poof, and we'll probably never know. I would look over the driveline (particularly the center area) to make sure there aren't any rocks or anything that might cause it to jam; just because it rolls freely on the bench doesn't mean it will when running because a rock or something may be in a position where it makes occasional contact enough to jam. I frequently get this on my CRT.5; a rock will jam between the axle and a-arm and I'll suddenly be doing donuts. Since the ERBE doesn't have a center diff, I would look at the center drive line as that is the only area that will actually stall the motor (the individual axles would diff out).