Kraton K8 jumping seems super nose heavy

[twicks0831]

So I got the kraton about a month ago. I ran it around the yard and immediately bought a max 5 esc and went to a 20 tooth pinion. The truck rocks now! But I’ve notice any jump, big or small it seems to be unbelievably nose heavy even when I pin it to level it out. It’s all completely stock as it was out of the box minus the pinion and the esc. Is this common? Thanks for any help!

 

[gotnitro]

Set the ESC to MAX punch level. That should help you stabilize it in the air when you stab it.

 

[KevinC]

You’re should buy a new pinion too......amp it up to 23-25 T.

 

[twicks0831]

I’ve got the punch turned all the way up already and I’ve tried it with a 23 tooth pinion as well and it seems to be the same way. I was thinking maybe something to do with diff fluids? Or the shocks being stiff? I might try the m2c shock pistons

 

[KevinC]

Ya check out the diff fluid threads in 8s section for further info. I’m not sure if this will help your nose down problem, but will help you tune your diffs appropriately for this rig.

With a 20-23-25 pinion, you should be able to correct it in the air from nose down attitudes, so something sounds a bit off. I know you’ve probably done this already so forgive me.......you are using the DX3 I presume?.......is the throttle speed toggle set to 100%? I accidentally bumped mine down to 75% once and ran it three times, wondering why it wouldn’t wheelie anymore.

Anyway, good luck and keep us posted.

cheers,
kev

 

[twicks0831]

I am using the dx3 yes, I’m so used to my xmaxx but I need to keep in mind the huge weight difference in the trucks. I’m gonna mess around with it more maybe try a 25 tooth pinion and go through the esc settings again. Thanks for your help!

 

[ItAintAtoy]

You could move the batteries back a bit, some 4s-packs are quite heavy.
The chassis has pre-drilled holes to move the battery tray back, you could go even further back by drilling new holes or ditching the stock trays for straps or something like that.

 

[beefy nugz]

Sounds like you need more wheel speed while flying.

 

[aametzger]

Maybe try staying in the gas longer after launch? With the 8s rigs I usually stay in the gas after launch until my nose is tilted up a little before backing off and then react based on air control needed. In my latest video i just posted today, I am doing some launches off of a big hill and the only nosedive I had was when I hit the brakes near the ground too hard. "Tortured RC" is my channel name if you want to check it out for reference of how my K8s launches. If the stock esc had drag brake, then what you describe sounds like drag brake is in play (but I know this esc doesn't have drag brake) Maybe check your throttle/brake trim adjustment. Neutral could apply a tiny bit of brake if trim is off. What happens if you put the truck up on a stand or block so that the wheels can run free. If you hit the trigger and then let off do the wheels keep spinning, or stop right away? just thinking out loud...

 

[japeape]

Maybe try staying in the gas longer after launch? With the 8s rigs I usually stay in the gas after launch until my nose is tilted up a little before backing off and then react based on air control needed. In my latest video i just posted today, I am doing some launches off of a big hill and the only nosedive I had was when I hit the brakes near the ground too hard. "Tortured RC" is my channel name if you want to check it out for reference of how my K8s launches. If the stock esc had drag brake, then what you describe sounds like drag brake is in play (but I know this esc doesn't have drag brake) Maybe check your throttle/brake trim adjustment. Neutral could apply a tiny bit of brake if trim is off. What happens if you put the truck up on a stand or block so that the wheels can run free. If you hit the trigger and then let off do the wheels keep spinning, or stop right away? just thinking out loud...

I had the same nose dive problem, are you saying that the rotational speed of the tires causes the car to tilt up or down? I let go of the throttle after launch and it nose dives heavily. If I stay on the throttle after launch it should keep the nose up?
I was debating putting more pre-load on the springs in the front.

 

[KevinC]

I had the same nose dive problem, are you saying that the rotational speed of the tires causes the car to tilt up or down? I let go of the throttle after launch and it nose dives heavily. If I stay on the throttle after launch it should keep the nose up?
I was debating putting more pre-load on the springs in the front.

Yes, you must continue to drive (throttle/ brake) the car while it’s airborne.

 

[aametzger]

??? what he said

 

[japeape]

Tried it yesterday, takes a bit of practice but it's fun!

 

[Primarrma]

Just make sure you're rear shocks are holding the weight, if you hit a jump and the rear compresses it will tag the chassis on take off and flip the car nose down. The extra weight of the esc motor will need to be compensated. You can try just adding more pre load, or heavier springs, but the M2C shock upgrades are well worth it, the shock shafts are super strong and the action of the shocks is night and day compared to stock with the upgraded pistons. I run slighter lighter oil than stock because I want the chassis the slap instead of bending the shock shafts.

 

[twicks0831]

I was going to try the m2c shock pistons so I’ll do the shafts as well. What weight do you use? Thanks!

 

[Primarrma]

I was going to try the m2c shock pistons so I’ll do the shafts as well. What weight do you use? Thanks!

I'd have to double check, but I think I went with 32.5w front and 35w or 40w rear. It sounds light but with the extra weight the shocks can rebound a little faster and the new pistons slow the rate enough over the bumps to not catapult the car on its head.

This is a link to a driving video, at about 3 minutes you'll see me hitting the ramps, this is when I only had the front shocks upgraded and the rear was hitting the ramp and pushing the nose down. Hope this helps mate.