Kraton arrma 8s exb roller big motor problem

[enk_rcs_on_tiktok]

I've been noticing that running high torque motors on a arrma kraton 8s exb roller (aka v1 8s exb) that the REAR diff cups shred the stock driveshafts.
I don't know if it's too powerful or it's an arrma problem but that's what I've been seeing. I've gone through 4 sets.
I've found that m2c works but just prolongs the enviable

 

[Saladshooter]

The advice on M2C's website is good guidance and may help:

 

[fredw90]

Vitavon makes diff cups and driveshafts with larger pins.

 

[SrC]

Guys are starting to just replace, press out and in new cross pins. I think this happens no matter the type of motor?
Am I wrong? I don't own one these....Yet.

 

[Moirae]

limiting shock travel definitely helps with this. I haven't had it happen since I added nylon washers to my shock shafts. You definitely want to pay attention to those m2c notes.

 

[KnowAir]

Too early for me to tell. I did install droop screws straight away on my v1 K8S. Fingers crossed.

 

[joshjosh]

I own both the M2C overkill and the Vitavon 8S shafts. I’m a M2C fan, but garsh these Vitavon cups and shafts look sweet! The pins are bigger.

 

[Dan2022]

I own both the M2C overkill and the Vitavon 8S shafts. I’m a M2C fan, but garsh these Vitavon cups and shafts look sweet! The pins are bigger.
View attachment 350437
View attachment 350438

are the larger pins replaceable in the vitavon ones? I got a set of the xmaxx ones, and was surprised the pines were retained by a grub screw.

Edit: They look replaceable.

 

[joshjosh]

are the larger pins replaceable in the vitavon ones? I got a set of the xmaxx ones, and was surprised the pines were retained by a grub screw.

Edit: They look replaceable.

They are replaceable, there’s a grub screw at the end.

 

[Niz55]

Definitely go with vitavon ones.
MC2 overkill ones I have used were absolutely trash. Broke more than the stock ones. Huge 8mm shaft with tiny stock size pin.

 

[Dan2022]

Guys are starting to just replace, press out and in new cross pins. I think this happens no matter the type of motor?
Am I wrong? I don't own one these....Yet.

This. I use drill blanks from Amazon or AliExpress and make my own pins for everything. With this case, on my 8s outcast the shafts last 2-3 before the diff end will shear off. Then it’s over, lol.
Edit: this also assumes the drive cups are good. The deeper and more pronounced grooves and flashing, the easier the pins break.

 

[joshjosh]

This. I use drill blanks from Amazon or AliExpress and make my own pins for everything. With this case, on my 8s outcast the shafts last 2-3 before the diff end will shear off. Then it’s over, lol.

I got my Vitavon axles and steering system in. I’ve been waiting for the PP 1/5 servo to come into stock to complete the build. Once I get all the pieces I plan on putting the Proline Trenchers back on and giving them hell. I just picked up a AGFRC servo, so I may just go with that, I just really hate to.

 

[Dan2022]

I got my Vitavon axles and steering system in. I’ve been waiting for the PP 1/5 servo to come into stock to complete the build. Once I get all the pieces I plan on putting the Proline Trenchers back on and giving them hell. I just picked up a AGFRC servo, so I may just go with that, I just really hate to.

I am going to try the vitavon ones on this rig probably on the rear. I posted in this thread in February that the xmaxx version was solid and may be good. The pp servo is great so far. Best I have used. Only brand I haven’t used was reefs big ones.

 

[joshjosh]

I am going to try the vitavon ones on this rig probably on the rear. I posted in this thread in February that the xmaxx version was solid and may be good. The pp servo is great so far. Best I have used. Only brand I haven’t used was reefs big ones.

I’m glad to hear you like it. It seems to be the best one that can run on BEC power. Of course most of the servo specs on the market are false. As with battery C ratings, there’s no regulation on any of it. Vendors inflate numbers all the time to sell. I do have moderate faith in the spec numbers from Futaba, NSRDC, PP, and AGFRC, in that order.