Which vehicle is this in and what T8 motor are you running?

Sorry!
Mugen mbx7r eco with 1900kv

I would gear up to a 16 and reduce current limit to between 60 and 80. 80c degrees isn't THAT hot maybe at the upper end of what you want to see but not going to melt down the motor. I run a 1900 in my 7r eco and 15 pinion seems ok for small tracks but 16 works better overall for me and temps aren't any higher. I also run timing profile 1.

Wouldn't gearing up on the pinion make it work harder? I was just reading the RX8 manual and it was saying damage would occur if you keep thermaling it, which is 220°F. 50°C is quite a distance from that.

Gearing is very track and surface dependent. If you have a larger track and or a track that has a lot of wheel spin, gearing up can help bring temps down.

Keep in mind this is a general statement and not always true but has worked for me. Hot esc cool motor=gear down. Hot motor cool esc= gear up. A lot of guys think that gearing down is the solution to a hot motor but sometimes if you gear up the motor is working in the more efficient rpm range and wheel spin is reduced so motor temps go down. Plus with a taller gear you have more wheel speed available to help keep the nose up when jumping.

One of the most common problems I see when people run a multi pole motor is being under-geared. Its very common that when you have a motor heat issue, you are spinning the motor at a higher RPM and not running in the powerband.

I don't know if this is the right place to ask, but I'm going to throw it out there. Running a RX8 Gen2 3 deg of timing and T8 1900 in my buggy. 10 min main, probably 85 degF or so out. ESC ran about 142, motor about 175. Should I gear up 1 tooth or leave as is? The temps are according to datalog.

I'd leave it...... Tekin has stated in the past; that under race conditions and time you are fine with temps below 200*f

A totally different question. I replace my bearings quite often in the T8 g2. What kind I'm bearings do you recommend?
I guess that also effect the heat!?

I wondering if gearing up one more tooth on the pinion will take me over that 200 deg temp on motor?

The bearings that come in our motors and the same ones we offer as replacements is a high quality ABEC 5 bearing. We have not seen any reason to spend the extra money of expensive ceramic bearings.

Scary images about undergearing and lack of cooling at EB48:

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Rotor blasted, ruined sensor board, wire has been desoldered from motor' B-post. Luckily ESC survived, and motor' stator too (no shortcuts b/w phases and body, and no Ohm spikes between phases), so only -84$ instead of 160 or 320 (for whole system).
After 2 mins after 'finish' i had 215F at the motor, blasted right before finish line after 8min final. Actually i've overheated it (a bit) before, so no complains about this. The only question to Tekin team is: is it possible to make sensor board w/o elements exposed to rotor?

I have done that twice also.
How often do you change bearings in T8?
How many hours between replacement do Tekin rekommend if the temps are ok?

I must admit I have ceramic bearings in my T8 1900kV motor. They were already installed when I bought a Durango DEX 408 V1 buggy second hand with the T8 installed. I Saw no reason to change them. But then again I only use the buggy for light bashing. It's mostly a display item.