Liberty's Kraton V4 speed project

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, and others.

LibertyMKiii

Aerodynamics speed junkie
Premium Member
Excellence Award
Build Thread Contributor
Messages
9,904
Reaction score
24,077
Location
TENNESSEEESSEEEEEE
Arrma RC's
  1. Limitless
  2. Mojave
  3. Typhon 6s
This will be my documentation thread for speed with the Kraton v4 6s (Blue)
I purchased this RC with specific intent to not turn it into a speed rig, and here I am…

Restrictions mostly as a challenge to myself:
#1 Retain the OEM body and look with exception wheels/tires & wing.
#2 Find limits of the OEM BLX system (both motor and esc)
#3 Run single 6s LiPo pack.
#4 Have fun and don’t pull too much funds away from my primary speed project.

Expectations are to find myself getting up to right around 100mph with the OEM BLX 185 system. (Should be fun to see just what it can do. )
Hopes if I could break 110mph on the factory electronics I would be very happy.

So Far I have reached 65.6 mph on a 100% original truck with the 15t optional speed gear installed. The only adjustment was spring pre-load and 500k diff fluid. I have been very impressed with this RC and imagine it will continue to impress me as I push into higher speeds.

Setup
GRP S3 (soft) speed tires (wish they made larger diameter sizes!!!!!!!!!!!!!!!!!!!!!!!!!!!!)
HR center diff spool
Revo 34t mod 1spur gear.
500k rear diff / original 30k front diff


39733
39732


TBR front bumper will likely need to come off although I like the added protection it provides.

-Liberty
 
Last edited:
I hit like on the post, but I cannot tell a lie. It looks like a caricature with those little wheels. You know when they draw a really big head with a tiny body kind of thing. But I'm anxious to see how fast you can get it to go on stock electronics. Good to know you're not the first one to do this:D
39734
 
I hit like on the post, but I cannot tell a lie. It looks like a caricature with those little wheels. You know when they draw a really big head with a tiny body kind of thing. But I'm anxious to see how fast you can get it to go on stock electronics. Good to know you're not the first one to do this:D
View attachment 39734
HA!!!! that is exactly how I picture it in my head.
I think the only large wheel that is belted and a street tire is the SRC road crusher but not the best track record over 100mph.
The BSR foams are 5.5 mm taller, which isn't much. For now this is sort of the best the market has to offer. (GRP 1/5 tires I am not a fan of )

GRP 1/8 98 mm
GRP 1/5 118 mm
BSR 1/8 103.5 mm
 
Last edited:
Looking forward to see how this goes..??

I'm toying with the idea of doing a similar thing with a different Arrma truck ? go as fast as possible with stock electronics problem is I've already started swapping stuff..?
 
Subbed to this @LibertyMKiii as you know I love my speed runners as well as am using all the stock Arrma electronics in mine still so will be interesting to see how they compare. Good luck with it all.

If you can would love to see some video of the Kraton going flat out, ...it's quite a beast. :cool:
 
Subbed to this @LibertyMKiii as you know I love my speed runners as well as am using all the stock Arrma electronics in mine still so will be interesting to see how they compare. Good luck with it all.

If you can would love to see some video of the Kraton going flat out, ...it's quite a beast. :cool:
Thanks for the Sub.
I like to capture video anytime I can. Waiting on my pinion gear to arrive and it will be ready for the first test run! (assuming it does not rain)
I am very anxious, my speed addiction is growing...
 
Passing along some learned info that I picked up today. GRP now makes a normal rim or hard rim on their tires. The hard rim is more difficult to find evidently as I never realized the different option.
Here is an example of the s3 (soft/med) compound tire I bought:

GRPGTX01-S3 and what I needed was the GRPGTJ01-S3
The J series is the Hard rim, which is better for high speed uses.

40057


When I received my GRPGTX01-S3 I immediately gave them a squeeze and noticed the rim was quite soft. It had been about 2 years since I had a set of GRPs but remembered them being very firm. Going to see if Hobby Heroes will take these back, if not ill see what the softer rim can do. I already mounted them and scratched up the plastic where the wheel nut makes contact on the rim.
 
You and me both ~ that Hot Racing centre spool pin coming out had us both. :p

What did you guys find as the best solution for that?
I was thinking of using set screws on each side that function as the pin. Traxxas axles use them called set pins

40062


-Liberty
 
What did you guys find as the best solution for that? I was thinking of using set screws on each side that function as the pin.

-Liberty
I used an old aluminium torch body that was the right size to act as a sliding collar. I made it the right length so I could put the pin in and then slide the collar over to hold the pin in place.
So far it is working a treat.

47 Fixing spool pin issue.JPG


50.JPG


51.JPG


52.JPG



I know @cootertwo used bearings that he found in the correct size which work in a similar way to my collar fix by sliding over the pin holding it in place. (y)
 
I used an old aluminium torch body that was the right size to act as a sliding collar. I made it the right length so I could put the pin in and then slide the collar over to hold the pin in place.
So far it is working a treat.

View attachment 40063

View attachment 40064

View attachment 40065

View attachment 40066


I know @cootertwo used bearings that he found in the correct size which work in a similar way to my collar fix by sliding over the pin holding it in place. (y)
That may be significantly easier than the method I was thinking of. Thanks!
 
With all this hype around the new Limitless model I just had to get out and do a speed run. I needed my speed fix.
(I am an addict and the first step to getting better is admitting I have a problem)
Knowing the HR spool has a design flaw I thought I'd risk it. Sure enough the rubber o-ring allowed the pin out and resulted in a RWD Kraton. Acceleration was ok although I didn't feel comfortable getting all the way up to full throttle. (geared for 130mph)
Braking was the issue, you could imagine trying to brake with only the rear wheels is just not a good thing.

40253


Result was 76 mph, when on the brakes the rear fish tailed and sent the rig over the curb where it began to cartwheel. It was far enough away that I couldn't see clearly but it was quite a few rotations. Zero damage drove it around back home to run down the battery.

 
With all this hype around the new Limitless model I just had to get out and do a speed run. I needed my speed fix.
(I am an addict and the first step to getting better is admitting I have a problem)
Knowing the HR spool has a design flaw I thought I'd risk it. Sure enough the rubber o-ring allowed the pin out and resulted in a RWD Kraton. Acceleration was ok although I didn't feel comfortable getting all the way up to full throttle. (geared for 130mph)
Braking was the issue, you could imagine trying to brake with only the rear wheels is just not a good thing.

View attachment 40253

Result was 76 mph, when on the brakes the rear fish tailed and sent the rig over the curb where it began to cartwheel. It was far enough away that I couldn't see clearly but it was quite a few rotations. Zero damage drove it around back home to run down the battery.

Is it just me or did that speed pass sound EXACTLY like a Tie Fighter!?!
 
It's fun ain't it! You'll have to do something to keep that pin in the spool, then go for the triple digits! Nice road to run on too!:)
I was at the hardware store this morning... didn't find anything good so I'll probably do the bearing race idea you did.
 
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