Kraton V4 Upgrade Fails (due to inexperience)! HELP Request

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, and others.
Bec is a voltage control system for your radio(and servos), it allows you to run a separate voltage for your receiver and servos to that of the esc output, it is nice to have not a necessity.

Diffs work best when filled to the correct level, virtually full, it should at the very least cover the cross shafts in the diff cup and even slightly more.

The shimmimg I've been talking about is outside the diff cup. Here is the greatest basher in the world talking about diff shimmimg, check out 7mins into the video for the shimmimg I think you need:
 
Hoping to get a little direction on some upgrades i recently made that aren't having as much impact as i hoped. In fact, except for the diff fluid, the "upgrades" have made negative or no difference in performance.

1) Rebuilt all diffs with 60k/500k/30k. There is a cracking sound that I thought was a loose P/S mesh so I tightened, but sound continues. Seems to be louder when throttling in reverse. I tried to match P/S mesh with my brand new Notorious for sound and feel and spacing, but the cracking continued. I'll tighten more tonight and run again, but really don't think it's that loose. Is there anything else that may be causing the cracking? It only makes it when hitting the throttle. IF it's not the P/S mesh could it be the motor?

2) Savox (SW-1210SG) servo - doesn't turn PL Thrasher tires anymore than stock did. Ordered stock tires from JRC. Waste of money there it seems.

3) Installed Tactic Tx/Rx and set EPA. Off the ground the wheels turn perfectly, however as mentioned in item (2) on the ground the Savox can't seem to turn the tires. Also, while driving it required a wide turning radius as in the width of the street. The St. D/R knob on is maxed to get full turn. What could be causing such a wide turn radius?

4) Set the punch to 9 and running 5000mah, 50C, 6S batteries. Is not as prone to wheelie as I though it would be so don't see a big difference in the punch setting. Is still very fast just not as punchy as i thought it would be.

Overall:
The Kraton still drives and is very fast top speed, but something just seems off. The new diff fluid works great. At full throttle the Kraton sets up evenly on all 4 tires while flying down the road (50ish mph)...but the cracking is annoying and can't turn as sharply as with stock. Also, not as punchy as I thought it would be on 9.

To restate my plan to try and address these issues is to tighten P/S mesh even more and put stock tires back on since Savox can't get it done. I have no ideas on the turning radius or why it's less punchy.

Thanks for reading and for any advice you can offer.
Hoping to get a little direction on some upgrades i recently made that aren't having as much impact as i hoped. In fact, except for the diff fluid, the "upgrades" have made negative or no difference in performance.

1) Rebuilt all diffs with 60k/500k/30k. There is a cracking sound that I thought was a loose P/S mesh so I tightened, but sound continues. Seems to be louder when throttling in reverse. I tried to match P/S mesh with my brand new Notorious for sound and feel and spacing, but the cracking continued. I'll tighten more tonight and run again, but really don't think it's that loose. Is there anything else that may be causing the cracking? It only makes it when hitting the throttle. IF it's not the P/S mesh could it be the motor?

2) Savox (SW-1210SG) servo - doesn't turn PL Thrasher tires anymore than stock did. Ordered stock tires from JRC. Waste of money there it seems.

3) Installed Tactic Tx/Rx and set EPA. Off the ground the wheels turn perfectly, however as mentioned in item (2) on the ground the Savox can't seem to turn the tires. Also, while driving it required a wide turning radius as in the width of the street. The St. D/R knob on is maxed to get full turn. What could be causing such a wide turn radius?

4) Set the punch to 9 and running 5000mah, 50C, 6S batteries. Is not as prone to wheelie as I though it would be so don't see a big difference in the punch setting. Is still very fast just not as punchy as i thought it would be.

Overall:
The Kraton still drives and is very fast top speed, but something just seems off. The new diff fluid works great. At full throttle the Kraton sets up evenly on all 4 tires while flying down the road (50ish mph)...but the cracking is annoying and can't turn as sharply as with stock. Also, not as punchy as I thought it would be on 9.

To restate my plan to try and address these issues is to tighten P/S mesh even more and put stock tires back on since Savox can't get it done. I have no ideas on the turning radius or why it's less punchy.

Thanks for reading and for any advice you can offer.
As far as that sound I would assume maybe you have a broken gear inside of your differential maybe a spiral gear just check to see if any of the teeth are missing off the gear or worn down or anything like that because my kraton did the same thing and all I had to do was change the main spiral gear in the diffs. And what Savox Servo did you get?
 
As far as that sound I would assume maybe you have a broken gear inside of your differential maybe a spiral gear just check to see if any of the teeth are missing off the gear or worn down or anything like that because my kraton did the same thing and all I had to do was change the main spiral gear in the diffs. And what Savox Servo did you get?
I think you're right. Late last night when I was finally bable to sit down and wrench I adjusted the motor mesh and then spun the wheels quickly and was able to replicate the crack sound and it's definitely coming from the front diff. I'm going to take apart tonight and look. I just rebuilt the damn thing, but lucky me on my first run a rock got jammed under spur gear so much that it stopped the truck I removed the rock and finished the battery with the cracking sound. Possibly when it happened. It's kind of a pain on the front bc I have to take my TBone front bumper off to get the front diff cover off. At least I'm closer to fixing the problem...I think.
The Savox servo is the sw1210sg or as I call it "the blue one" ?
Your ESC has to support the 7.4v for the servo. If you're on the stock blx ESC it only has a 6v built-in BEC. You would have to get an external BEC that supports higher voltages. I think they run bout $20 for a decent one.
Bec is a voltage control system for your radio(and servos), it allows you to run a separate voltage for your receiver and servos to that of the esc output, it is nice to have not a necessity.

Diffs work best when filled to the correct level, virtually full, it should at the very least cover the cross shafts in the diff cup and even slightly more.

The shimmimg I've been talking about is outside the diff cup. Here is the greatest basher in the world talking about diff shimmimg, check out 7mins into the video for the shimmimg I think you need:
I see said the blind man. BTW, I hate that shim! Also, I'm glad he restated those part numbers for the shims bc I just ordered some. At first I didn't think he was and I was gonna have to search YT for another video...but he stated them again. Nice guy!!
 
Last edited:
I think you're right. Late last night when I was finally bable to sit down and wrench I adjusted the motor mesh and then spun the wheels quickly and was able to replicate the crack sound and it's definitely coming from the front diff. I'm going to take apart tonight and look. I just rebuilt the damn thing, but lucky me on my first run a rock got jammed under spur gear so much that it stopped the truck I removed the rock and finished the battery with the cracking sound. Possibly when it happened. It's kind of a pain on the front bc I have to take my TBone front bumper off to get the front diff cover off. At least I'm closer to fixing the problem...I think.
The Savox servo is the sw1210sg or as I call it "the blue one" ?


I see said the blind man. BTW, I hate that shim! Also, I'm glad he restated those part numbers for the shims bc I just ordered some. At first I didn't think he was and I was gonna have to search YT for another video...but he stated them again. Nice guy!!
Why do you hate those shims?

I'm not wanting to upset you, but this isn't the way I tighten my mesh, it's a great way because you can do it without pulling your internal diff cup apart. I actually space my bearing with 8x10x0.2mm shims between the main diff gear and the out drive bearing. If you're in a hurry you might be able to get these shims more easily. It's a good time to upgrade your bearings if you haven't already, these can wear and make the diff looser than it should be.

This is another reason I prefer the RPM front bumper or the TBone Typhon front bumper, not worries pulling the diff out, just remove the tie rod ends on the sway bar link, undo the lower shock pin retainer screws remove pins lift socks up and undo the 4 gearbox cover screws the diffs out.
 
Last edited:
Yeah buddy I feel you on having to take the T-bone front bumper off I have an RPM front bumper and I have to do the same thing every time I take the diff off. But overall it is a pretty easy process to get the diffs out .one other thing I suggest that you do is make sure that they sent you diffs with enough diff oil in them from the factory mine weren't filled up enough so I topped them off at first and then I ended up changing the weight of the diff oil. The Savox 1210 Servo is great I've heard wonderful things about it, I use the Eco power wp120T servo and it works wonders with the kraton. Especially with my hex8 esc where I can program it to 7.4 volts as opposed to 6 volts. I use the hobbystar 1730kv 4092 motor. And my kraton rips bro
 
Here is where I fit the shims...

20190518_033023.jpg
 
Here is where I fit the shims...

View attachment 38454
For the center diff? Don't think I have any on my outcast... I have the HR mount and front diff stand/holder.

For front/rear the diffs, I use SWX-101018 SWorkz 13x16x0.2mm and put them outside the bearing. Easier since they fit over the cup, then you can add/remove as needed without taking the diff apart.
 
Why do you hate those shims?

I'm not wanting to upset you, but this isn't the way I tighten my mesh, it's a great way because you can do it without pulling your internal diff cup apart. I actually space my bearing with 8x10x0.2mm shims between the main diff gear and the out drive bearing. If you're in a hurry you might be able to get these shims more easily. It's a good time to upgrade your bearings if you haven't already, these can wear and make the diff looser than it should be.

This is another reason I prefer the RPM front bumper or the TBone Typhon front bumper, not worries pulling the diff out, just remove the tie rod ends on the sway bar link, undo the lower shock pin retainer screws remove pins lift socks up and undo the 4 gearbox cover screws the diffs out.
I hate the shims bc they're so flimsy and it was some what of a pain to slide diff back in and diff correctly lined up. It would keep slipping out. I'll use the r duberbash tip and use grease next time. I did upgrade all bearings on every diff. Will need to do the same on bell crank eventually.
Here is where I fit the shims...

View attachment 38454
So no extra diffs inside the cup?
 
Last edited:
Your ESC has to support the 7.4v for the servo. If you're on the stock blx ESC it only has a 6v built-in BEC. You would have to get an external BEC that supports higher voltages. I think they run bout $20 for a decent one.
Any BEC brand name you can recommend?
 
For the center diff? Don't think I have any on my outcast... I have the HR mount and front diff stand/holder.

For front/rear the diffs, I use SWX-101018 SWorkz 13x16x0.2mm and put them outside the bearing. Easier since they fit over the cup, then you can add/remove as needed without taking the diff apart.
I have started doing it on the inside of the bearings as I can always get the shims, they are a standard wheel axle bearing so they are cheap and easy to get. It's a pain if the diff is too tight in the case, but if it's still too loose you can just add a larger shim to the outside. I had to shim my center diff when I put my hr mount in it would move back and forth way to much.

I agree that it's easier the way you describe, though I kept bending shims and had a hard time finding them without long shipping times.
I hate the shims bc they're so flimsy and it was some what of a pain to slide diff back in and diff correctly lined up. It would keep slipping out. I'll use the r duberbash tip and use grease next time. I did upgrade all bearings on every diff. Will need to do the same on bell crank eventually.

So no extra diffs inside the cup?
It is unlikely the noise you're hearing is the inside of the diff cup, most likely the main input drive gear slipping on the main diff gear, the reason I started putting shims on the inside of the bearings (outside the cup on the main diff gear, you will see where the bearing sits on the tube like flange on the metal gear, they sit over that and push the bearing outwards) is because it's easy to damage the shims when you do it the other way and too fiddly to insert the diff.
 
Last edited:
Any BEC brand name you can recommend?
Turnigy has some cheap options @ hobbyking.com. Castle has one but I think you need the castle link to set it. Maybe someone who uses one can suggest a good one. Mine runs fine at 6v so i don't have one myself, but it might solve your issue as the 1210sg gets a lot more torque at the higher voltage and def cheaper to get one of these than a whole new servo. ;)
 
I just pulled apart my Noto center diff. I had shimmed it as per the old thread on this forum. All of the internal shims were concave, which leads me to believe I didn’t need them. Shimming these new diffs is the boogeyman. If you strip one out it’s because your gearbox is cracked, the gearbox cover is loose, or you landed hard under power. I beat the piss out of my 6s trucks and the only shims I add are the outside ones on the ring gear side.
 
I just pulled apart my Noto center diff. I had shimmed it as per the old thread on this forum. All of the internal shims were concave, which leads me to believe I didn’t need them. Shimming these new diffs is the boogeyman. If you strip one out it’s because your gearbox is cracked, the gearbox cover is loose, or you landed hard under power. I beat the piss out of my 6s trucks and the only shims I add are the outside ones on the ring gear side.
Thanks for sharing that. That's what I had heard somewhere else regarding these 2019 models not needing the internal diff shims...which is good.
 
Do the 2019's have shims already?

My 2018 outcast did. They were just soft and worn after a couple packs. Also, they didn't have any behind the larger sun gear so the pins were rubbing on the o-rings. I took out the ones that came in it on the 4 planetary gears and put all 6 from the mugen kit in it and they seemed to spin nice and smooth before oil was put back. Haven't cracked one open since... that was last July a week after I got the truck.
 
I have started doing it on the inside of the bearings as I can always get the shims, they are a standard wheel axle bearing so they are cheap and easy to get. It's a pain if the diff is too tight in the case, but if it's still too loose you can just add a larger shim to the outside. I had to shim my center diff when I put my hr mount in it would move back and forth way to much.

I agree that it's easier the way you describe, though I kept bending shims and had a hard time finding them without long shipping times.

It is unlikely the noise you're hearing is the inside of the diff cup, most likely the main input drive gear slipping on the main diff gear, the reason I started putting shims on the inside of the bearings (outside the cup on the main diff gear, you will see where the bearing sits on the tube like flange on the metal gear, they sit over that and push the bearing outwards) is because it's easy to damage the shims when you do it the other way and too fiddly to insert the diff.
Here's my front shim. Is that normal?? ?
IMG_20190518_003709607.jpg
 
Hoping to get a little direction on some upgrades i recently made that aren't having as much impact as i hoped. In fact, except for the diff fluid, the "upgrades" have made negative or no difference in performance.

1) Rebuilt all diffs with 60k/500k/30k. There is a cracking sound that I thought was a loose P/S mesh so I tightened, but sound continues. Seems to be louder when throttling in reverse. I tried to match P/S mesh with my brand new Notorious for sound and feel and spacing, but the cracking continued. I'll tighten more tonight and run again, but really don't think it's that loose. Is there anything else that may be causing the cracking? It only makes it when hitting the throttle. IF it's not the P/S mesh could it be the motor?

2) Savox (SW-1210SG) servo - doesn't turn PL Thrasher tires anymore than stock did. Ordered stock tires from JRC. Waste of money there it seems.

3) Installed Tactic Tx/Rx and set EPA. Off the ground the wheels turn perfectly, however as mentioned in item (2) on the ground the Savox can't seem to turn the tires. Also, while driving it required a wide turning radius as in the width of the street. The St. D/R knob on is maxed to get full turn. What could be causing such a wide turn radius?

4) Set the punch to 9 and running 5000mah, 50C, 6S batteries. Is not as prone to wheelie as I though it would be so don't see a big difference in the punch setting. Is still very fast just not as punchy as i thought it would be.

Overall:
The Kraton still drives and is very fast top speed, but something just seems off. The new diff fluid works great. At full throttle the Kraton sets up evenly on all 4 tires while flying down the road (50ish mph)...but the cracking is annoying and can't turn as sharply as with stock. Also, not as punchy as I thought it would be on 9.

To restate my plan to try and address these issues is to tighten P/S mesh even more and put stock tires back on since Savox can't get it done. I have no ideas on the turning radius or why it's less punchy.

Thanks for reading and for any advice you can offer.
Ring gear is chewed up guaranteed. It happens if you land with front tire under load.
 
Old Thread: Hello . There have been no replies in this thread for 90 days.
Content in this thread may no longer be relevant.
Perhaps it would be better to start a new thread instead.
Back
Top