I too would guess braking. The stress from acceleration depends on the voltage of the battery, but in braking the voltage could potentially go higher than the battery voltage (at least compared to the battery's voltage under the load of acceleration).
SH Z-Car, Custom Crawler, 8s Savage, 12s XTM XLB 1/7 buggy, 4wd 4-link rear/IFS Pro4 truck, Custom Hyper 10 Short Course, Belt-Drive Mammoth ST 1/8 truggy, 4s 17.5 MM Pro HPI Blitz
Yeah, I'm thinking about higher voltage spikes from motor, and transients?
“The modern astrophysical concept that ascribes the sun’s energy to thermonuclear reactions deep in the solar interior is contradicted by nearly every observable aspect of the sun.” —Ralph E. Juergens
I did a little experiment with a 10,000uF cap I had, and it doesn't arc a whole heck of alot, not much more than stock Quark.
I found these on eBay, they are 1500uF, might be a little big to mount. What do you think? HERE
“The modern astrophysical concept that ascribes the sun’s energy to thermonuclear reactions deep in the solar interior is contradicted by nearly every observable aspect of the sun.” —Ralph E. Juergens