Help installing modern electrics in a TQ10

[gsharp]

Hi Guys I'm looking for some help. This forum has been a great source of inspiration and information. I've recently returned to the RC hobby after many years away. I've been recommissioning / restoring my old TQ10 for some backyard bashing.


As you can imagine after 10+ years of storage all my old NiCad packs were in a pretty bad sate. Most of them were chucked immediately but one old 8.4V pack held enough charge to test the radio and make a few laps of the garden. Looking around for replacements it seemed that getting a couple of LiPo packs was the way to go longer run times etc. I already had a LiPo charger for some other RC experiments so I ordered some 2S 4200mAh packs along with a X-Car 45A brushed ESC from HobbyKing. I installed everything last night and took the car for a spin and every thing seemed fine for about 5mins until all the smoke fell out the motor. I should say that the motor was a recently purchase 21t etronix spot tuned can fitted with a 16t pinion.
My question is where have I gone wrong?
Is the power system I'm using to much for the motor?
I know there are some HobbyKing haters out there but all there other stuff I've used has been ok.
Is the old gearing to high/low for the new electronics?
Have I made some fundamental error in my modernisation / upgrades?
What motor would you recommend for a basher setup with LiPo's?
Any help would be greatly appreciated as I kinda down about the whole thing.
I've got an vintage Kyosho Turbo Ultima II with a mechanical speed control that I'm now wary of connecting a LiPo to in case it costs me another motor.

[harvey]

I like your under tray!
The LiPo batteries are very powerful! You may have simply overheated your motor. Was it hot while it was smoking? You can burn the insulation off the windings and then it kind of shorts, drawing way too much current. If this is what happened, your motor is wrecked. Excessive heat is bad for magnets also, in addition to burning the lube out of the brushes (they go blue, and are then harder on the comm).
I run 4000mah LiPo's with brushed, but always stop halfway through the run, or when the motor gets hot.