I just got a Losi Tenancy MT, running on 2S. I know heat is an issue with these trucks. I have a Castle motor fan, and it came with a 12T pinion gear. I run in my yard alot, I know grass is a high load. But I only get a 10 min run time before it shuts off.

Anybody figured out how to fix the heat issues ?

New motor and esc, 1/8th scale system on 3s. Like a 2650-2800kv... on 3s. Will give you gobs more trq, a little bit more speed at way cooler temps. Then run 4s for high speed runs.

I don't have the MT verision but I do have the Truggy edition, we have experienced just what you are talking about. We have tried the CC fan just as you have and still got the same results. I have read that some people replace the motor with a lower KV to reduce temps and also I have been told since the can has no cooling fins built in that a cooling setup that will attach to the motor and increase the motors cooling surface area and add fins would be better. I have not looked in awhile but will tomorrow when I go to Hobbytown and let you know if I find anything.

You fix the heat issues by gearing down. I bet you can gear down significantly without losing any actual top speed in grass. A GPS speedometer is your friend when gearing your vehicles.

I use an exotek fan mount and a yeah racing fan on my motor in my tenacity db. drops the temps by 30 degrees.

Fans help too, but seriously, gear-down.

Both of my short-course trucks run modified 550 brushed motors, because apparently I'm a masochist. (seriously though, I just think brushed motors are retro-cool. but I digress...) So gearing matters a lot more on those trucks, because I don't want to fry the commutators. (again. *sigh*) When I was testing the first one, I initially geared it for a specific speed on-road, and needless to say it overheated like crazy off-road, even with a fan on the endbell. After burning out a (very expensive) custom-made armature, I geared it down from 17t to 13t, only dropped the speed by 2mph on-road, and didn't drop the speed at all off-road. Why? Because driving in grass meant there was an upper limit to the chassis' ability to push the grass out of the way, and any additional wheel speed was just wasted as wheelspin.

So seriously, if your motor is overheating, do a quick run off-road with a GPS speedometer, and then start gearing-down until you start to lose speed off-road. Then gear back up 1-2 teeth to make sure your off-road speed is maxed-out. Your motor will thank you for the reduced workload, and you'll still have the exact same amount of fun as before.