gearing to run 2s

[ndrsroark]

Hello i need some help with gearing i have a kit yeti that i have installed my tekin rx8 and pro4 4000kv set up in and am running 2s batteries i have the stock gearing 64t spur and 16t pinion and the esc stays about 98° but my motor is getting 160° to 170° im looking for advice on pinion and spur to bring motor temp down and add a little snap to throttle response . Thanks

[351Beno]

Just drop your pinion down some teeth. If you do the math 64/16=4 so going down to a 14t pinion 64/14=4.57. When you down teeth on the pinion you lose top speed but gain acceleration motor temp goes down but esc temp may go up. Its the opposite for the spur. Even one tooth makes a difference. Its hard to say what gear is best so i always buy a few and go from there.

[Dbdynsty25]

The gearing on the Yeti's is super conservative, so you're never really going to fly around tracks, but 351 is right, drop the pinion down to 14T and you'll have plenty of yank on the bottom end w/ that motor/esc combo. It's gonna be pretty damn slow at the top end tho. Pluses and minuses to everything I suppose.

[ndrsroark]

Thanks guys i was hoping not to have to lose top end but i guess its gotta happen because motors getting to hot .

[StatGSR]

to keep or increase the top end you would have to switch to 3S and gear down

[8000ft]

Two speed gearbox and gear up to 60 or 56 spur. I estimate about $150 for gears and servo. It's the best of both worlds, slow for crawling and a bit more top end.

At best with 2S you are spinning that motor at 33,600 RPM, which isn't very much but sticking a 3S in there would just surpass it's red line. However if I remember correctly you should be able to set a top limit via the hotlink.

By stepping up to 3S you will get better launch and top speed both with lower motor temps because your motor won't be working as hard to move the truck on 12 volts as it does on 8 volts.

Remember, anything can be solved by throwing money at it

[ndrsroark]

Ok so i ordered some 3s batteries and have been doing some research and from what i have gathered my rx8 with pro4 4000kv motor is a grenade waiting to detonate i have never ran this set up on 3s before but i do have a castle 1410 3800kv 540 can and a castle 1415 2500kv 550 can will this set up be ok or will i need to install one of these castle motors to be on the safe side ..I was hoping to stay with the tekin pro4 to run sensored . Im not a big fan of cogging . I do monitor temps often through telemetry on radio and every once in a while i check with temp gun do i run the tekin and monitor or just swap motors and if so which one is better suited for track style with rocky conditions not a crawler style Thanks

[StatGSR]

Just gear it down, no need to swap out the motor imo.

[ndrsroark]

Originally Posted by StatGSR

Just gear it down, no need to swap out the motor imo.

Thanks thats what i thought ..... i will gear down and watch temps .

[8000ft]

your Pro 4 with a 3S will be just barely in the red zone, at a full 12.6 volt charge and running at full throttle you will hit a theoretical 50,400 RPMs.

But how often are you at full throttle for any length of time? And as soon as you drop one tenth of a volt (12.5) you are at 50,000 rpm, soooo I'd say run the 4000kV motor.