First Bully build

[pcgab]

So I've been wanting to try an MOA and make a few comps with it in 2021. I've been waiting for the kits to come back in stock, and got lucky and bought one on RC4WD's one day black Friday sale recently.

The build was fun enough, certainly pretty easy, and only had a few very minor issues. Thanks to some research in advance of the build, I ordered a nice set of Avid bearings to replace all of them in the axles. Some of the hardware isn't that great, thankfully I have a ton of m3 socket caps, button heads, etc. on hand to replace with.

The tires as they come are a little stiff it seems, so I cut some pins and sanded the sidewalls a bit on the front's. I'm running narrowed Crawler Innovations 5.25 (CWR-1044) dual stage, with soft outer. I'm currently not using the tuning ring, but plan to experiment with it in the next week or so. I'm also going to mod the rear tires a bit, and put in some CI foams in them as well. I have a new set of Ibex on hand, and a set of the fantastic Dlux Fab 2.2 beadlocks. I'm waiting on some hub spacers for the fronts, and another delivery of foams from CI (5.5 softs).

I'm really enjoying the rig so far, learning to use dig, and am slowly iterating through suspension setup/tweaks.

I'll rattle off a list of parts used and a few quick pics of the rig as it is now.

RC4WD Bully II MOA Kit
Dravtech short shocks, soft in front, medium in rear, 25wt oil in them currently.
Avid rubber bearings in the axles.
Dlux Fab 2.2 beadlocks
Ibex, Bully comp tires, and CI foams all around.
Holmes Hobbies Snubnose Revolver's - 1400kv
Castle Mamba Micro X ESC's
Holmes Hobbies SH500V3 servo.

 

[pcgab]

A few thoughts, and ramblings...

I noticed some of the RC4WD rod ends don't move as easily I would like, so I replaced them with Revo ends, 5347, 1942 (iirc), and the 5525 long ends. This helps the links move more freely throughout their range of motion.

I'm waiting on a pair of motor covers from Holmes so I don't continue to lathe down the outer cases on the rocks. I meant to order them earlier, apparently I overlooked that idea.

I took the top half of the cases off the mamba's, and I will probably de-case them further sometime soon. I would like to be able to get them squeezed into the middle of the lower skid, ideally. I suspect, however, that I may end up putting one in the center, and one on the front axle, on top of the gears. That, or I may fab a drop tray that attaches to the top of the gear case, and drops back behind it a bit. If I go that route, I'll probably try to get the receiver on there as well. We'll see what I actually come up with.

I have some ideas on a few things I would like to upgrade. I'll do my best to enumerate them here, if anyone has any insight, or feedback, please speak up

1 - Servo mount, might try the Dlux mount, see if I can get the bottom of the servo closer to, or flush with the bottom of the axle tube.

2 - Dlux knuckes, bigger shafts, etc. This would help bring the front axle into a much more durable component, and would help me improve the geometry and tuning ability a good bit, as I currently understand it. I am using the 8 degree chubs and knuckles currently, and am not completely convinced that's the best route, ultimately.

3 - Dravtech medium shocks for the rears. I'm currently using the shorts with ~6mm spacers in them. I'll try some 3mm spacers and see if that is enough to squeeze a bit more range of motion back there. I love the dravtech shocks from Dlux. I bought the Channel lock brand 926 snap ring pliers, and now building them is significantly more easy. I run them on all my rigs.

4 - Tires and foams of course. I've got a set of Ibex, will probably grab some ruptures, rovers, etc. to narrow and try out. I'll order some Voodoo pins too. I really like the CI foams, and plan to use some combo of them in all the tires. I've had great success with their products.

There are probably plenty of other ideas I'm forgetting at the moment....

Cheers,
Gable

 

[pcgab]

Now that I've run quite a few packs through the rig, and made a few adjustments, I'm really starting to love it. It certainly has it's flaws, and isn't perfect, but I'm enjoying it quite a bit.

I need to clock the front axle up a bit more, and I want to dial in some more caster, but I think I'll need to re-think steering if I do so. I'll experiment with that soon enough.

One thing that bugs me is the front lower link mounts at the chassis. The angle that they mount means the rod ends bind with the chassis plates pretty quickly. This binding is amplified when the rig is flexed on an obstacle.

I'm thinking I may try some bent rod ends on the lower links at the chassis. I don't want to grind down the chassis there as that would leave it very prone to break, I would think.

I'll post some pics when I try it out...

 

[pcgab]

I dialed in some more caster and adjust the steering link a bit. This has improved steering, and the ability to grab on ledges, etc.

I'm going to try the bent link idea for the chassis connection point for the front lower links and see if I can improve the binding situation there.

 

[pcgab]

I got a set of JConcepts Ruptures recently, and decided I would mod them pretty heavily. I trimmed all the side lugs, shaved and sanded the sidewalls, then narrowed them by ~15mm. I've got one done, and need to narrow another tonight. I'm hoping to try them out this weekend. I have some CI 5.5 foams that I narrowed, soft outer, but I think that might not fill these enough, so I order a few sets of 6" comp cut, soft and medium outers to try.

I left the inner ribbing at the inner ring intact, as I am hopeful it helps keep a bit of inner sidewall support.

A few pictures for now:

 

[nathanotis]

Watching this one.

Noob question: what does sanding the tires accomplish?

 

[pcgab]

Watching this one.

Noob question: what does sanding the tires accomplish?

Sanding the sidewalls thins them a bit, to help them soften. This makes it easier for the tire to conform some to the rocks and provide better grip.

Cheers,
Gable

 

[nathanotis]

Sanding the sidewalls thins them a bit, to help them soften. This makes it easier for the tire to conform some to the rocks and provide better grip.

Cheers,
Gable

Do you ever treat them with WD40? I know this is common practice with smaller, 24 scale tires to soften them.

 

[pcgab]

Do you ever treat them with WD40? I know this is common practice with smaller, 24 scale tires to soften them.

I haven't tried that. Shaving and sanding the sidewalls, plus cutting some pins made them much better. I think the Ibex's with no mod's perform better, fwiw.

 

[xxlostonexx]

nice build.

i have both tires as well. the IBEX on my comp rig are dialed in. Simple green is a good way to soften up tires and clean of the residue from manufacturing. i did the WD40 stuff way back but that left the tires feeling oily.

how do you like the brushless motors? i preferred brushed over the brushless on MOA. my futaba remote let me set up to have overdrive to the front and underdrive to the rear.

good luck with the rest.

 

[pcgab]

nice build.

i have both tires as well. the IBEX on my comp rig are dialed in. Simple green is a good way to soften up tires and clean of the residue from manufacturing. i did the WD40 stuff way back but that left the tires feeling oily.

how do you like the brushless motors? i preferred brushed over the brushless on MOA. my futaba remote let me set up to have overdrive to the front and underdrive to the rear.

good luck with the rest.

I switched back to the Ibex today and ran a few packs, on my 'rock garden' boulders, they are clearly superior on these moss boulders. I think on more 'craggy' rocks the narrowed ruptures might do better. I'm going crawling with some friends tomorrow to a spot with some decently varied rocks, so I'll likely try the ruptures in the front, and maybe even the rear.

I've got another un-used set of Ibex's, I'm going to narrow them a bit. I think they might work better a touch more narrow, hopefully get more contact pressure, not to mention I can get a little more steering.

I also have some nice upgrades coming. I ordered some Dlux knuckles, for his 8mm stub shafts, tungsten weights in aluminum knuckles, true ackerman arms, the works. I also ordered a set of his shafts for the bully 2 axles. These should be an awesome upgrade, help me maximize steering a bit, and hopefully make the front axle damn near bulletproof.

I'm also getting some kydex tomorrow from a friend. I'm going to make an electronics tray that hangs off the back of the front axle. I'll mount the front axle's esc (mamba micro x) on the lower part. This will allow me to move the esc for the rear axle to the front of the tray on the chassis. In doing so, I'll get more weight off the chassis, put it on the axle and lower down.

When I make the electronics tray, and upgrade the shafts and knuckles, I'm also going to re-wire and optimize the wiring. I've got a lot of extra wire zip tied in various places, and I would like to eliminate that, once I confirm the electronics tray and location of esc's works as I would like.

I have a hacked GT3, and have underdrive/overdrive on one of the momentary switches, so I can click in 10% increments OD to the front, or rear. I don't use it much, as yet, but I intend to practice it for certain situations. To be perfectly honest, I'm still 'mastering' , I use that term rather loosely mind you, dig currently. I have a nice set of boulders in the back with 6-7 challenging gates that I can use to test, and practice. This is helping me quite a bit.

I use the purple Simple Green to clean new tires, and typically when I switch out wheels, or foams, I'll wash them again with it. I've noticed it brings them back to 'stock' stickiness very well.

If I remember to, I'll try to get some pics tomorrow, we're hitting a newer spot that I tried last week, and it should be loads of fun.

Cheers,
Gable

 

[pcgab]

I narrowed a pair of Ibex's, and narrowed some CI 6" foams, comp cut inners, soft outers, with no tuning ring. This combo is a bit too soft and 'empty' for me. It works very well, but more foam support will help. I'm going to add the tuning rings and try that as soon as the rain goes away.

I also narrowed, cut, shaved, sanded, etc. a new pair of J Concept Ruptures. This time I shaved the sidewall ring, and the inner ribs. I put in CI foams, narrowed by me, comp cut inners, soft outers with the tuning ring. The Ruptures are a bit taller than the Ibex. I like the foam support pretty well with this combo, but may try medium outers at some point as well. I definitely like this cut/shave/etc combo better than the first pair of ruptures I mod'ed. I will likely shave the sidewall ring and inner ribs on that pair soon as well, or just run them in the rear, where a bit more support is likely a good thing.

I got a few pairs of bully pins for Christmas as well, so I'm thinking I'll do a narrow and pin cut/shave on a pair of those, to have some more options. I need to order more foams too, and wheels. I like to be able to run a few obstacles, swap the tires and run them again to compare.

I think I'll have my Dlux knuckles, shafts, etc. in the next week or so, I'm super excited about getting those setup.

Do folks tend to run narrowed tires in the rear of their 2.2p rigs, or just in the front? The steering gain with the narrowed Ibex's is awesome, and on the right rocks they seem to bite better.

Some pics of the tires. You can see where I marked one of the Ibex's to cut, I think I might cut the next set even on both 'sides', ie: cut a strip out of the center, instead of offset by one pin.