Big Rock Here we go! 😂

[kaladeth]

 

[Rowdyray]

This should be good. I give it about 5 minutes. Lol.

 

[MrTitanium]

Your diffs are gonna need psychological therapy cause they’ll have no idea wtf hit them.

 

[Rowdyray]

Your diffs are gonna need psychological therapy cause they’ll have no idea wtf hit them.

Unless he shoe horns in the new 4S center diff. Then I give it 10 minutes.

 

[Luke66]

I can't tell if this is a BR 3S or a Nero BR...

 

[Bustedaw11]

View attachment 352758

I like your style

 

[MrTitanium]

I can't tell if this is a BR 3S or a Nero BR...

It’s the 3s. The Nero BR has the shocks in the horizontal position and wouldn’t be visible from that photo angle.

 

[RC Steve]

A 1717 motor will fit if you dremel out the rib between the motor and the ESC.?

Well, I thought it was a good idea.

 

[J.Rambo]

View attachment 352758

Do you have metal diffs in there? If not, you're gonna need em. I got max 10 and 3674 in mine rn +center diff conv.. 3s is fine. 4s ran for about 2 packs then started hearing grinding. Opened up diffs and nothing but polymer powder in there . Metal diffs will hopefully fix this. I'm gonna upgrade to max 8 w/ supass 4092 eventually. I was also interested in some OC4S arms. At this point, I shuda just bought an OC4S and a Bigrock 3s chassis. . Any how, I can't wait to see how yours turns out! Looks sweet thus far!

 

[NitroK]

Your diffs are gonna need psychological therapy cause they’ll have no idea wtf hit them.

No truer words to express the pending carnage.

I only upgraded the motor on my BRCC 3s and all kinds of stuff started falling apart. Kaladeth, please let us know how it turns out.

 

[King blitz]

I can't tell if this is a BR 3S or a Nero BR...

Shocks are upright it's a 3s oops jumped the gun to quick .someone answered question already.

 

[Barmaleus]

I don't know what's going on, but I like it.

 

[kaladeth]

Road Block #1

The 1717 seems to be too big although I have heard others were able to just drop one in (eg. into a Vendetta).

This is a Big Rock V3 3S BLX with the stock motor mount plate and case ARA311032.

The motor, when mounted, has a big enough diameter (47 mm with fins) that ends up lifting the motor casing off the chassis (by about 3mm), preventing the mount from sliding and slotting into the back clips.

I took off the front case to have a better look. For the drive shaft hole to stay aligned with the center line, the mount plate needs to twist ~4 degrees counterclockwise to accommodate the motor. (Left side 3mm down, right side 3mm up)

If not, from this pic you can see the motor shaft needs to go about 3mm lower in order to be vertically centered in the mount to fit the mounting holes.

It seems like I need a different mount or make my own custom mount case.

I can also just switch to a stock big rock 6S esc and motor and call it a day, but wanted to explore all options first.

Any thoughts or ideas?

 

[Luke66]

Okay, IK this is off-topic. But some one mature needs to say this.

Are you sure this is a good idea?
NVM of course it is! all those blown diffs and driveshsafts are parts of the fun!

 

[kaladeth]

Got it in there. This is literally pushing it:

Road Block #2

I’m going to need a bigger pinion to move the motor further away from the drive shaft (17t to 20t or 21t). Or get a thinner drive shaft. Yes I ran the motor and yes those are groves on the plastic driveshaft made by the fins on the motor.

 

[NitroK]

Looks so pretty. On a positive note, you have eliminated two of the main problems with the Big Rock;
1) Gap between stock motor and chassis which results in bent motor mount on hard impact
2) Pebbles getting into the space between center drive shaft and motor, resulting in premature wear of drive shaft.

 

[kaladeth]

Test fitting with a 3D printed gear, the 21T looks good. I would say the minimum is a 20T and the maximum is a 22T.

 

[kaladeth]

Pinion set. Ready to mount the ESC!

 

[Neelis]

Poor driveshafts

 

[NitroK]

@kaladeth when you get it running, please send the footage to Arrma R&R.