Kraton Kraton 4S - Steel CVD couplings question, product page change

[Gedrick]

Hello again folks!

Yesterday I joined HorizonHobby's new social network thing and one of the top (only?) posts was about a Kraton 4S and how they've already found drivetrain problems. They posted some pictures [which I screenshotted and attached] and it seems others have had this problem, but from an earlier build. My understanding (another thread here mentioned it) is that Arrma made some last minute changes to the construction of the CVDs. Here's the issue as detailed by a poster on RCNation:

I took a look at the product page now versus back in June when the page was first created, to see if possibly they updated the product page to reflect this change, and guess what? It seems like they did.

You can see the old version from June here:
https://web.archive.org/web/2022061...v2-blx-speed-monster-truck-rtr/ARA4408V2.html

and the current one:
https://www.arrma-rc.com/en/product/1-10-kraton-4x4-4s-v2-blx-speed-monster-truck-rtr/ARA4408V2.html

The interesting thing I found is that they added another row of images to the feature grid, one of which boasting about what seems to me, to be the CVD upgrade (also attached).

In the CVD blurb, it says this: "These feature strong, hard wearing steel couplings and axles." now I'm not an expert on CVDs but it seems like they _did_ change the couplings to steel (like the poster said they needed to do in the first attached image annotation), so issues the earlier K4 builds had should be a thing of the past. Is this accurate? Because I'm nervous that if I break a driveshaft I won't be able to get a replacement (they're out of stock until December!)

The reason I'm asking is because the Kraton 4S sitting in my garage was ordered from AMain as soon as they went back in stock in mid-August, so I'm really hoping it's the new version with the steel couplings. Is there a model number change between the "early" release models of the K4 versus the ones in stock now?

Lots of questions here but mainly just paranoid I've got a brand new car in my garage with a major design flaw and no spare parts currently available. I'd rather be able to check the box and send it back than open it up and deal with that. Thanks in advance, you guys.

 

[Robbbbbb66]

Hello again folks!

Yesterday I joined HorizonHobby's new social network thing and one of the top (only?) posts was about a Kraton 4S and how they've already found drivetrain problems. They posted some pictures [which I screenshotted and attached] and it seems others have had this problem, but from an earlier build. My understanding (another thread here mentioned it) is that Arrma made some last minute changes to the construction of the CVDs. Here's the issue as detailed by a poster on RCNation:

View attachment 240546

I took a look at the product page now versus back in June when the page was first created, to see if possibly they updated the product page to reflect this change, and guess what? It seems like they did.

You can see the old version from June here:
https://web.archive.org/web/2022061...v2-blx-speed-monster-truck-rtr/ARA4408V2.html

and the current one:
https://www.arrma-rc.com/en/product/1-10-kraton-4x4-4s-v2-blx-speed-monster-truck-rtr/ARA4408V2.html

The interesting thing I found is that they added another row of images to the feature grid, one of which boasting about what seems to me, to be the CVD upgrade (also attached).

View attachment 240547

In the CVD blurb, it says this: "These feature strong, hard wearing steel couplings and axles." now I'm not an expert on CVDs but it seems like they _did_ change the couplings to steel (like the poster said they needed to do in the first attached image annotation), so issues the earlier K4 builds had should be a thing of the past. Is this accurate? Because I'm nervous that if I break a driveshaft I won't be able to get a replacement (they're out of stock until December!)

The reason I'm asking is because the Kraton 4S sitting in my garage was ordered from AMain as soon as they went back in stock in mid-August, so I'm really hoping it's the new version with the steel couplings. Is there a model number change between the "early" release models of the K4 versus the ones in stock now?

Lots of questions here but mainly just paranoid I've got a brand new car in my garage with a major design flaw and no spare parts currently available. I'd rather be able to check the box and send it back than open it up and deal with that. Thanks in advance, you guys.

I have a outcast V1 upgraded with V2 driveshafts and have not had a issue yet.

Also, Jennysrc.com has full sets V2 driveshaft for $50, not ideal price if you break a shaft but it will get you running again.

 

[BentShaft]

My Outcast had some kind of update done to it after initial assembly and packaging, not sure what. I understood that a change was made to the driveshafts but I don't know what exactly that involved. Anyway, on mine the inner cup that attaches to the diff outdrives is still plastic. And I've yet to see one that had that part in steel.

That said, this piece interfaces with splines on the diff outdrive and that's what takes the load, not the set screw. The set screw IMHO is just to keep the plastic part from sliding off the splines. But it is a pretty soft plastic from what I can tell so maybe the splines are just deforming to the point that it fails.

 

[Gedrick]

My Outcast had some kind of update done to it after initial assembly and packaging, not sure what. I understood that a change was made to the driveshafts but I don't know what exactly that involved. Anyway, on mine the inner cup that attaches to the diff outdrives is still plastic. And I've yet to see one that had that part in steel.

That said, this piece interfaces with splines on the diff outdrive and that's what takes the load, not the set screw. The set screw IMHO is just to keep the plastic part from sliding off the splines. But it is a pretty soft plastic from what I can tell so maybe the splines are just deforming to the point that it fails.

Out of curiosity, when did you get your Outcast? From my reading the issue was happening with ones from 2+ months ago (a few YouTubers who got them had this issue).

 

[razorrc]

I don't agree with the RCNation poster, V2 parts seem fine. They updated the plastic piece holding the driveshaft onto the diff to better retain the metal clip that covers the CVA pin.

My favorite part of the thread --

"Joshua Wallace
I believe the most correct person here is Razor RC."

 

[HZRDOS]

I don't agree with the RCNation poster, V2 parts seem fine. They updated the plastic piece holding the driveshaft onto the diff to better retain the metal clip that covers the CVA pin.

No issues with either of mine yet....but u also don't drive much in rocky areas. I know some people thing that is the issue. Also have some mud guards being delivered for both of them. That will help also

 

[razorrc]

No issues with either of mine yet....but u also don't drive much in rocky areas. I know some people thing that is the issue. Also have some mud guards being delivered for both of them. That will help also

Maybe I'm wrong, but I think we're talking about two different things here. Joshua Wallace thought the coupler needed to be made out of metal because he kept tearing his apart (due to too tight slipper).

The other issue is the metal ring clip being knocked off, which is what they "fixed" in the delay. If that's still getting knocked off due to rocks, yeah, I could believe that, but that's not what the original poster was complaining about.

 

[BentShaft]

Out of curiosity, when did you get your Outcast? From my reading the issue was happening with ones from 2+ months ago (a few YouTubers who got them had this issue).

A week ago.

 

[HZRDOS]

Maybe I'm wrong, but I think we're talking about two different things here. Joshua Wallace thought the coupler needed to be made out of metal because he kept tearing his apart (due to too tight slipper).

The other issue is the metal ring clip being knocked off, which is what they "fixed" in the delay. If that's still getting knocked off due to rocks, yeah, I could believe that, but that's not what the original poster was complaining about.

Maybe. He mentioned the last minute changes, assumed it was the ring clip issue.
So are you saying there were (2) changes to the CVDs?
Ohhhh...I see what happened

 

[Gedrick]

Maybe I'm wrong, but I think we're talking about two different things here. Joshua Wallace thought the coupler needed to be made out of metal because he kept tearing his apart (due to too tight slipper).

The other issue is the metal ring clip being knocked off, which is what they "fixed" in the delay. If that's still getting knocked off due to rocks, yeah, I could believe that, but that's not what the original poster was complaining about.

These are awesome replies guys, I really appreciate the help. It seems like it’s not as big a deal as I thought, but rocky terrain seems to be the kicker here. Interesting.

@HZRDOS which mud guards are you Picking up? I’ve got some rocky terrain by me as well and figure it can’t hurt.

 

[Robbbbbb66]

These are awesome replies guys, I really appreciate the help. It seems like it’s not as big a deal as I thought, but rocky terrain seems to be the kicker here. Interesting.

@HZRDOS which mud guards are you Picking up? I’ve got some rocky terrain by me as well and figure it can’t hurt.

@HZRDOS is getting some mud guards from @Tex Koder I think.

@Tex Koder is a great guy, PM him and he will most likely send you some for a small fee ( all his products are 3D printed)

 

[Tex Koder]

@HZRDOS is getting some mud guards from @Tex Koder I think.

@Tex Koder is a great guy, PM him and he will most likely send you some for a small fee ( all his products are 3D printed)

Somebody called my name?

How may I be of service?

 

[HZRDOS]

@HZRDOS is getting some mud guards from @Tex Koder I think.

@Tex Koder is a great guy, PM him and he will most likely send you some for a small fee ( all his products are 3D printed)

You are correct sir.

@Tex Koder is a great guy and a pleasure to deal with. Highly recommend.

 

[Gedrick]

No issues with either of mine yet....but u also don't drive much in rocky areas. I know some people thing that is the issue. Also have some mud guards being delivered for both of them. That will help also

You are correct sir.

@Tex Koder is a great guy and a pleasure to deal with. Highly recommend.

Wow, this is a tight knit place, as I was told! That’s really cool you guys. I’ve been wanting to get into 3D printing for this reason but it’s daunting, plus someone’s always figured it out before I’d have a chance to

Well @Tex Koder if you’d be interested in discussing business with the FNG around these parts, that would be pretty cool and very appreciated!

 

[Tex Koder]

Wow, this is a tight knit place, as I was told! That’s really cool you guys. I’ve been wanting to get into 3D printing for this reason but it’s daunting, plus someone’s always figured it out before I’d have a chance to

Here's the thing..
There's no better time to start then Now.
Yes, there's Always someone who has Created it/Done it/Made it -whatever something- BEFORE you, But that should never be the reason for you to not begin yourself.
Part of the process is the journey.

There's Lots to wrap your brain around..
You can learn it , it can be done.

Well @Tex Koder if you’d be interested in discussing business with the FNG around these parts, that would be pretty cool and very appreciated!

Glad to be of assistance.
Feel free to take a look at the design process and resulting 'product' here >
https://www.arrmaforum.com/threads/calling-on-the-3d-printer-guys.55150/page-2#post-798726

 

[Gedrick]

Here's the thing..
There's no better time to start then Now.
Yes, there's Always someone who has Created it/Done it/Made it -whatever something- BEFORE you, But that should never be the reason for you to not begin yourself.
Part of the process is the journey.

There's Lots to wrap your brain around..
You can learn it , it can be done.




Glad to be of assistance.
Feel free to take a look at the design process and resulting 'product' here >
https://www.arrmaforum.com/threads/calling-on-the-3d-printer-guys.55150/page-2#post-798726

Hey I appreciate it! I'm a software engineer so the "it's been done already" concept really does ring true with a lot of things - but ultimately I'd love to be able to make some of my own parts, perhaps making a few bucks on the side financing this already expensive hobby.

I dig the look of the guards though, they look sick!