Gearing an 8xl Maxx - Wrong Motor?

[Sorb3t]

I have a FLM Gorilla UE Maxx 3.3 truck I've put together over the last few years and am loving it. Just took it to the track for the first time (been bashing and breaking up until now - lotsa of mods = lots less breaks ) and I don't know why I didn't sooner. It was great. Anyways, while I've noticed my motor getting hot in the past, with many laps nonstop it is getting VERY hot, 200F+, hot enough that one of the motor leads de-soldered from one of the plugs. I am running a Feigao 8XL smooth can with the RCM Heatsink, Quark 125B w/heat mod RCM heatsink and fans, BEC, Gorilla single speed tranny (my racing ended when *something* stripped inside the transmission, maybe steel idler? haven't opened it yet), a 51 tooth Ofna Mod 1 spur with 20 tooth pinion (I've tried 18 tooth, motor gets 190F when bashing) with 2X 2s2p batts parallel, UE 8 Spider diffs, 40 bowties. I went up on the spur size thinking that would cool the motor. ESC always stays warm/good temp, runs a little warmer w/20 tooth but no problems, batts always stay cool. Should I go w/ a bigger pinion? Is this a problem that will only be fixed with a better motor e.g. Neu? I don't want to continue melting leads obviously. Any help appreciated. Thanks.

Here's what I'm running:

Differential Ratio: 3.3076923076923075
Transmission Ratio: 1.7222222222222223
Other Ratio: 1
Spur Tooth Count: 51
Pinion Tooth Count: 20
Total Voltage: 16.8
Motor KV: 2084
Tire Diameter (inches): 5.8
Tire Ballooning (inches): 0
Motor Current Draw: 0
Motor coil Ω: 0.0073
Spur/Pinion Ratio: 2.55 : 1
Total Ratio: 14.52628 : 1
Tire Circumference (inches): 18.22 inches (462.82 mm)
Total Motor Speed: 35011.2 RPM
Vehicle Speed: 41.59 mph (66.8 km/h)
Estimated Adjusted Speed: 39 mph (63 km/h) - 5% loss
Effective KV Value: 2084
KT constant: 0.65 oz-in/A