Big Rock Big Rock cc - speed test + bashing

[jym73]

No breakages which aren't already known.

I think i will put the t-bone front bumper as soon as it is available on amain otherwise the shipping are way too expensive for my country. Next run will be with the Granit fortress MT wheels.

I started a review here : https://www.rcgroups.com/forums/sho...A-Big-Rock-Crew-Cab-3s-BLX-1-10-4WD-MT-Review

 

[jym73]

Upgraded parts :
T-bone front bumper : https://tboneracing.net/collections/bigrock-3s/products/10095-tbr-xv6-front-bumper-arrma-big-rock-3s
GPM Racing front hub carrier : https://www.gpmracing.com.hk/en/pro...10-4WD-GRANITE-4X4-MEGA-MOSTER-TRUCK-AR102680
Gpm Racing cvd (on front) : https://www.gpmracing.com.hk/en/pro...-10-4WD-BIG-ROCK-CREW-CAB-4X4-3S-BLX-AR102711
Arrma Granite Wheels : https://www.arrma-rc.com/part/AR550045

The GPM racing drive shaft are quite hard to put in place, mainly the differential outdrive which is a very very very thigh fit. This is how i did :
- I removed the C-hub from the a-arm by removing the C-hub pin.
- I removed the front shock absorber to have enough room for working.
- I removed the stock CVD.
- I put the GPM "drive cup" on the differenital axle, just in front of the axle, by turning it we can feel the "spline shaft" are aligned.
- I took a 10mm with normal head screw, for 2.5mm hex driver. The screws provided by GPM are too short at this step.
- I put the screw in the hole in the gpm "drive cup" and hold the drive cup with a 1.5mm hex screw driver in the hole for the pin for avoiding the drive cup and diff. axle to turn..
- Then i screw the screw.
- I checked if the "drive cup" was well aligned by turning the opposite wheel, if it wasn't aligned, i hammered the drive cup a little bit to align it.
- I contiuned to screw, it will be hard to tight, i screwed it as far as i could do, this push the drive cup in place.
- When it was too hard to screw, i changed the screw for a 8mm one and repeat the same step above.

As i show at the end of the video the main damages are : a velcro strap broken and the plastic center axle shredded by a small pebble. It isn't that much when we see the bad landing it took. The surface is aslphat covered by dust, sand and gravel. After a closer look i also broke the small bar which held the front aluminum a-arm's hinge pin brace on the T-bone front bumper.

The car isn't so easy to handle on this kind of loose surface. When you hit the throttle too fast the rear end tend to drift on the side quickly. But the handling is better with wider tires. The motor/esc tend to cog sometime. The reverse doesn't respond quickly sometime also. There is still the problem of gravel/pebble which tend to bind the steering quite often. Two shock absorbers leak like crazy. But overall the car is fun to use and seems pretty solid with the upgrade.


Front a-arms aluminum brace mod :

As i have broken the small plastic part which is on the T-bone front bumper, the one which hold the aluminum a-arms brace, i have lost the front aluminum a-arms brace. So i decided to do a quick modification to avoid to lost it again.

I did two holes with a 2.5mm drill tip. I threaded the holes with a M3 tap thread.

Two M3x10 screws and two M3 washers and it is done!

If i see that the a-arms hinge pins go out, then i will hammer a little bit the aluminum arround the 4mm hole to avoid them to move out.

 

[arrmadillo]

Surface is very loose, could see the approach to ramp was hard to get right but you figured it out later in the vid.

Good place to drift though, like to see the Infraction on that surface. ?

Overall enjoyed it, good job!!

 

[jym73]

Surface is very loose, could see the approach to ramp was hard to get right but you figured it out later in the vid.

Good place to drift though, like to see the Infraction on that surface. ?

Overall enjoyed it, good job!!

Thks.

Yes the surface is very loose and as you mention the approach to the ramp was tricky. The steering servo doesn't help also, a bit on the too slow side, i will surely chnage it. But this allow to learn how to use the throttle to try to keep the car in way we want

 

[jondilly1974]

Hey @Notorious J did you see our latest graduate running his BRCC? ????

It almost seems like you should turn the ramps around 180 degrees. You had much better ability to hit the rear of the ramps with accuracy than the front ???

Subbed

 

[Notorious J]

Hey @Notorious J did you see our latest graduate running his BRCC? ????

It almost seems like you should turn the ramps around 180 degrees. You had much better ability to hit the rear of the ramps with accuracy than the front ???

Subbed

I think the fact that they are black over the white gravel made them blend in too much. You could see that he was having a hard time finding them on his approach. Definitely a graduate of the JDNJ Academy though. Likely an honor student.?‍??‍?

 

[jym73]

It almost seems like you should turn the ramps around 180 degrees. You had much better ability to hit the rear of the ramps with accuracy than the front

It would be too easy

think the fact that they are black over the white gravel made them blend in too much. You could see that he was having a hard time finding them on his approach. Definitely a graduate of the JDNJ Academy though. Likely an honor student.

I would like to see what you would do in the same condition .

 

[jym73]

I just added a quick modification about the front a-arms aluminum brace in the second post.

 

[jym73]

@slick2500 asked me photo of the BRCC body on the ECX Ruckus in the Mojave thread, here it is :

Both cars with their respective body :

Bodies size comparison :

Reversed bodies :

Note that the holes aren't aligned with the body mounts, so they would be a little bit more down with new holes.