Getting rid of rear-end axle-hop or "chatter"

[lornecherry]

... Edited for content to move this discussion with permission

[lornecherry]

J, here's what's worked for me. At this time, I'm purposely only using genuine upgrade Kyosho parts ... (except tires), as I want to be sure that it's not an aftermarket part causing an effect, as the cars are so new.

Differential:
The stock differential is horrible, mine was tight, grindy and inefficient on both cars right out of the box. You thus need to install the Kyosho ball differential and use the two or three ring spacer setting, as per the instructions. Lubricate the differential (there are right and wrong ways to do this, use a very small amount light machine oil or dry graphite ...never grease). Both rear wheels should spin very smoothly with no hint of binding. While you are back there, get rid of the stock bushing and add ball bearings.

Front Suspension:
Next check your front suspension. Out of the box mine was almost non-functional, there was binding and very little travel. Chuck the stock bushings and lubricate the suspension and bearings. There is an article on the Atomicmods site about polishing kingpins; I don't go quite that far, but I do make sure that everything is very smooth up front.

Rear Suspension:
If you've changed to a carbon fiber H plate, I would change back to the stock plastic; you want max flexibility back there. I remember the reason we changed to carbon fiber on the Mini-Z was because the stock plates broke in a day. That is not a problem with the d'Nano, and from what I can see a the only reason to use carbon fiber H plates is for stiffening up the rear; exactly the opposite of what you want to do if you've got chatter (which is equivalent to full scale "axle hop".)

These setup tips will be old-school for those with Mini_Z experience, and I'd be lost on this little car without having setup so many of those cars previously and thus understanding the Kyosho philosophy on quality construction with a few suspect or poorly performing parts. At this price, the d'Nano should come with full bearings and ball differential.

I've tested this setup on both carpet and EVA foam (the smooth side) and it works well. It does take time to settle in and if you take some very sharp corners with full-grip, you may still get some chatter, but it's certainly much more drivable than stock.

[-J-]

Thanks again for the help Lornecherry.

Differential:

I've added ball bearings all around, so I can check this off the list. I've sanded the diff plates smooth with high grit sandpaper (it was HIGH, just can't remember the exact grit rating), which is definitely worth doing, just be sure you use a ultra high grit sandpaper so you don't increase friction. Anyway, I rebuilt my diff and only lubricated it with a little, light bearing oil. Seems to work well. Both rear wheels spins and work freely, but I'm still not happy with the Kyosho diff. I don't think it differentiates very while, but that's for another topic. I'm gonna keep playing with the provided spacers and may try to find other springs that may work.

Front Suspension:

Again I've added bearings all around so we don't have to worry about that. After buying numerous spring sets, I've finally found a set of each hardness that seats properly within itself with compressing and is nice and smooth. I've just double checked and the front suspension seems to be working properly.

Rear Suspension:

The past couple weeks I've been playing with the Atomic h-plate set. Almost all the h-plates in the Atomic set are softer than the Kyosho plates, but like you said, the stock h-plate works the best on the carpet of anything I've found so far.



Again thanks for all the tips and tricks. I look forward to your next writeup. The only thing that I haven't tried that you suggested were the atomic tires. They're on the list for this weekend's trip to the track. Then again it could be the surface under the carpet, which is quite rough, and my malicious driving. :P

[arch2b]

due to my mini-z experience, i've always perferred soft h plates vs. stiff. for mini-z, i actually use custom made lexan h plates that vary in stiffness and are nearly indestructible. they will tweak if left bent but easy enough to flatten out.

stock mini-z h plates are very succesptible to breakage due to force and angle of impacts and amount of exposure of the rear end. i find it very hard to believe the dnano will have the same problems unless you get nailed just right on a rear wheel.

[lornecherry]

arch, if it is easier, feel free to move these two threads (the one on the transmitter and the one on the suspension) to the hop-up or mod category.

[arch2b]

done

[-J-]

Just came home from the dNaNo track near me. I've done everything Lornecherry suggested, and had a decent amount of track to test the setups. Everything Lornecherry suggested really helped cut down on 85% of the chatter. Anyone suffering from chatter problems or handling issues in general should try some of Lornecherry's ideas.

The only thing that I could add would be that Atomic 25s up front and 20s in the rear is a good tire combo for those that like their cars twitchy! For those who running on carpet, who want just a little more front and rear traction than the stock setup provides, try Kyosho 40s up front and 10s in the rear.

Thanks again Lornecherry.

[arch2b]

has any one tried the atomic ball diff already on sale on thier egr website?

[-J-]

Originally Posted by arch2b

has any one tried the atomic ball diff already on sale on thier egr website?

I went by Atomic R/C yesterday and they said it wasn't available yet. They were still in the final stages of testing.

[arch2b]

Originally Posted by -J-

I went by Atomic R/C yesterday and they said it wasn't available yet. They were still in the final stages of testing.

odd, they are selling it in thier main online distribution webstore already, HERE.

[-J-]

Originally Posted by arch2b

odd, they are selling it in thier main online distribution webstore already, HERE.

Could've been a miscommunication with the language barrier and all. He clearly said they weren't available yet, but maybe that's not how he meant it. I'm not sure.

[fraz]

Originally Posted by -J-

Could've been a miscommunication with the language barrier and all. He clearly said they weren't available yet, but maybe that's not how he meant it. I'm not sure.

I've had two on order since they first posted. I will holler as soon as I see them

[-J-]

Originally Posted by fraz

I've had two on order since they first posted. I will holler as soon as I see them

Would appreciate it.