SCX10 ii top speed and 75mm shocks?

[Mighty_Bohab]

I have been running a SCX10 ii for about 2 months now. I bought the Raw Builders Kit, so far I love it. I have some 75mm shocks coming in for it. Trying to lower the center of gravity so I can take tighter turns faster. What is the fastest motor I could safely install in my rig without destroying it. Right now my locked diffs are grinding badly when I apply the brake. I tried to shim the input to the axle but I can't fit anything in between the axle and the driveshaft. How can I fix this it is grinding all the teeth off my beveled gear. It mainly happens in the front but after a heavy bashing session yesterday the rear is clicking and grinding now too. Is it because of the plastic AR44 axle? I have some metal ones coming in soon. Thanks in advance for any and all help.

 

[Jboucher]

This is not a basher at all.
The tiny AR44 gears are too weak for bashing and being locked kills the turning radius.

You need to at least turn off the drag brake from the ESC and get better foams for the wheel to prevent folding at speed.

This is a slow crawling scale rig. You should buy a traxxas slash or an Arrma to bash.

Maybe the axial yeti at least for scale look and open front diff.

Sent from my Pixel 2 XL using Tapatalk

 

[svt923]

The tiny AR44 gears are too weak for bashing and being locked kills the turning radius.

I'll disagree with that point, the machined AR44 gears have held up fine to the biggest power I have thrown at them (Puller Pro 3500kv on 3S and Pro4HD 2500kv on 4S are the craziest setups I have used in my 8-9 trucks with AR44 gears).

The issue here is the sintered gears and one piece axle housings from the Raw Builders Kit. The few sets of 1-piece axle housings I have all allowed the ring gear/spool to move side to side in the housing which ruins the mesh under power. That movement when combined with the weaker sintered gear material will cause gear skipping under hard acceleration or braking. Once you hear your gears skipping, they are already toast.

To keep everything running smoothly under mostly any amount of power, pick up some machined axle gears (Vanquish, Axial, SSD, Hot Racing, etc - the 6 bolt style would be optimal), machined lockers, and shims in 5 mm and 7mm. Shim all side to side movement out of the ring gear/spool by installing the 7mm shims between the ring gear and bearing like this:

You know where the 5mm shims go. If there is any play in the pinion shaft, shim it out. Yokomo makes a great 5mm shim set that you can get from Amain which has several thicknesses perfect for pinion shimming.

All this shimming stuff applies to all axles and is needed on an axle by axle basis since no 2 housings are exactly the same. Once properly shimmed, the AR44 gears will hold up to most anything (no matter how poorly a SCXII handles and flies in my personal experience:mrgreen.

 

[Mighty_Bohab]

I am actually running a 5200KV motor in my Axial rig right now, and after about 1.5 months, I started to hear grinding. Mainly during braking but now also under moderate acceleration. I know this motor is way to fast and I am planing on getting a Mamba X 2280(which is still too fast).But the motor isn't really the issue, it is the plastic axle that is actually allowing the gears to lose their mesh. It deforms quite significantly under heavy load. The nylon it is made from just has way to much flexability. I have purchased some aluminum axles to test my theory out. This covid plague has caused minor shipping delays, but I will survive.