Kraton Help determining sudden issue

[joshada2828]

I was out just messing around in my backyard today and my kraton exb was driving just as it should. I did run into a big tree I usually turn around by going around but I was literally going five miles an hour max and it actually kind of just rides up it more than just head on collision. Everything seemed fine immediately after but a few mins later I noticed it was pulling extremely hard to the left under acceleration(opposite side than the tree incident). Here’s a video and it clearly goes straight until I hit the throttle. I really hope nothing happened to the servo since it’s a brand new savox monster tourque with only two runs so far. Any help would be appreciated as I can’t find anything online so far.

UPDATE- I came across this with the rear diff. So maybe the power is being distributed uneven and definitely not normally at the least. I’m surprised it happened so randomly. I’ll keep trying to diagnose and hopefully someone else has some insight!

2nd update- Found the probable culprit. looks like the pin holding the outdrive snapped and also messed up some of the gears inside. Hopefully I’m able to get this back together the way it was after I go pick up the parts tomorrow lol

 

[SrC]

Don't overlook a BENT Steering Ackerman plate. Typical damage even after a front end love tap sometimes. Wheel alignment also can be off. Most probable. Steering can drift under load suddenly. I think you are over thinking things, jumping right to the Diffs first. Unless you know the diffs are already shot from wear or damage. Otherwise, you are Beating yourself up. You will end up chasing a Ghost. Start with the basics. Steering being the issue, look it over much better. The naked eye has a hard time seeing a tweaked Steering belcrank, tie rods and the Ackerman Plate that is hidden from view under the top plate.
I gave up on the Savox and other expensive servos. Bashing destroys most any servo. Leaves your wallet crying all the time. DS3235 35KG AMZ $34.00 servos suit just fine. Cheap enough to always have a new spare one on the side. We are only bashing here. Arrma's have so much slop throughout the steering and all, makes no sense putting in any high end supposed "Precision" servo.
My 2 Sav. 1210s sucked for the coin I payed. No more. Bashing just needs a 35kg servo at a minmum, and Firm, adjusted Servo saver. Servos are consumable items. Don't expect them to last. Just one wrong impact and they are all toast. Driver error gets the best of them. Paying Big coin for a servo, won't prevent driver error from bricking them.

 

[joshada2828]

Don't overlook a BENT Steering Ackerman plate. Typical damage even after a front end love tap sometimes. Wheel alignment also can be off. Most probable. Steering can drift under load suddenly. I think you are over thinking things, jumping right to the Diffs first. Unless you know the diffs are already shot from wear or damage. Otherwise, you are Beating yourself up. You will end up chasing a Ghost. Start with the basics. Steering being the issue, look it over much better. The naked eye has a hard time seeing a tweaked Steering belcrank, tie rods and the Ackerman Plate that is hidden from view under the top plate.
I gave up on the Savox and other expensive servos. Bashing destroys most any servo. Leaves your wallet crying all the time. DS3235 35KG AMZ $34.00 servos suit just fine. Cheap enough to always have a new spare one on the side. We are only bashing here. Arrma's have so much slop throughout the steering and all, makes no sense putting in any high end supposed "Precision" servo.
My 2 Sav. 1210s sucked for the coin I payed. No more. Bashing just needs a 35kg servo at a minmum, and Firm, adjusted Servo saver. Servos are consumable items. Don't expect them to last. Just one wrong impact and they are all toast. Driver error gets the best of them. Paying Big coin for a servo, won't prevent driver error from bricking them.

I initially was inspecting those things but ruled them out pretty quick. I ended up finding a snapped pin on the left side rear drive cup which was pushing all the power to the right tire which in turn was turning the car to the left under acceleration. In the second video I posted I had realized that the right rear tire was spinning freely so I knew something had to be up with the diff at that point.

But on servo topic, my $150 savox honestly doesn’t feel much different than the sun $100 savox I have. The monster edition one has almost 3 times the torque but I don’t really see as big of a difference as you’d think you’d get. In the future I’ll probably shoot for speed and a baseline torque of at least 350 or so. The monster edition still is nice though, I just maybe would’ve gotten the monster speed one in retrospect

 

[parcou]

I initially was inspecting those things but ruled them out pretty quick. I ended up finding a snapped pin on the left side rear drive cup which was pushing all the power to the right tire which in turn was turning the car to the left under acceleration. In the second video I posted I had realized that the right rear tire was spinning freely so I knew something had to be up with the diff at that point.

But on servo topic, my $150 savox honestly doesn’t feel much different than the sun $100 savox I have. The monster edition one has almost 3 times the torque but I don’t really see as big of a difference as you’d think you’d get. In the future I’ll probably shoot for speed and a baseline torque of at least 350 or so. The monster edition still is nice though, I just maybe would’ve gotten the monster speed one in retrospect

Some YT videos show taking snap rings or shims to the servo saver to better turning or power to the wheels. This is for the Kraton EXB but has been done to the RTR.

Based on that, I have read and seen the Kraton EXB, and some RTRs have a very weak servo saver. Your servo could be doing its job, but the servo saver is eating power.

Shims worked well for my EXB.

 

[RCbuzz]

Wow.. a thicker EXB pin as well. Must have been a pretty good impact.

Good Luck on the repairs