The MT’s I have are 190kv and the TB’s are 170 so it’s not apples to apples. I went with the MT’s because I liked that big support bearing and was tired of taking the cans off to clean out debris.
Nah brother. They won’t die.
100a is what I ran mine at when I had a Nazare. They did just good but tbh. Never really paid attention to motor temp 
3 Likes
In college when I was winding.my own wye outrunners, I took a blowtorch to magnets and it takes only so much heat before the strength of neodymium disappeared. 380 I think. Forgot. But they immediately just loose it.
Maybe 280f
2 Likes
Running 80A with the motor faceplate mod and big bearing removed (risky can/shaft wise, I know) I top out at 60’C, which is pretty good. 
One hit might compromise the motor can very hard though. Risk/reward. 
1 Like
How do I do this mod?
My big bearing has completely seized up after a particularly wet and muddy session. Any tips on cleaning or replacing it? I can’t figure out if there’s a dust-cap on it (it’s not budging if there is).
I’m surprised to see how much corrosion is building up there as well. Is it worth brushing this back and then sealing it with conformal coating or something?
1 Like
Remove the big bearing and use them till they die. The only way. 
1 Like
You can’t fix a seized bearing, might last longer if you replace it with a sealed one.
1 Like
Christ almighty. It only had 50 Kms on it! 
Any clues as to what bearing I’d need to replace it with?
1 Like
the stator iron is very easily rusted because its a weak iron or something along those lines (dont know the english name), a bit of rust is not that bad.
1 Like
Yea, my bearing died after 50km as well
I forgot what size that bearing was, don’t have them anymore. You can measure the id/od/width with calipers and get the same thing with a 2RS suffix, I’ve seen them on amazon.
2 Likes
It should have markings on it?
5 Likes
6809 2RS. Even then. I still recommend not using them. Even high quality big bois will seize because of centering issues. Heck, even original NSK 6809 DD bearings seize up. It just be like that. 
2 Likes
maybe the ones with extra room between the balls and the races work since they allow for more heat expansion?
oh wait those are the DD i think 
Not really, it’s very weird with these motors. They have varying center offsets. Some might be fine, but others will require some insane amount of force to reassemble with proper bearings and die fast.
DD are free float shielded NSK bearings, the shielding doesn’t touch the balls compared to 2RS.
3 Likes
It’s a 6809Z.
I soaked it in oil for a day or so have flushed it through a few times. Now it’s spinning quite nicely again.
Reassembled it. Now I’m hearing what I’m guessing is a rubbing between the can and the stator. Can was thoroughly cleaned and oiled and looks perfectly aligned so don’t know wtf is up now.
1 Like
Do not use the bearing. 
Yes, it will result in unknown issues. It’s been heavily tried to make them disappear to no avail…
1 Like
Problem categorically was the bearing. There was no can/stator rub. Pulled it off and replaced it with an SKF 61809/6809 2RS1. It’s like night and day. Smooth as silk.
12 Likes
anyone know the size of the rear bearing
mine seems to have blown up and died inside the motor leaving just the outer race left.
anyone know how i can remove the outer race and replace the bearing?
thanks