TRX4 sport cog mods?

[Spence]

Hi guys, I was curious what the best mods to optimize the side hilling and vertical ability of the trx4 sport kit..

Currently, I have brass axspeed knockoffs of beef tubes "patties" that actually added about 2-3mm of width on each side, and as well as axspeed c hubs, and brass outer portal boxes all around, along with a brass link mount kit..

Would the next step be a front battery mount? I mean this thing does have a pretty relatively high COG..

Not sure what else can be done. Thinking of shock towers with those little keys that you can buy to get more flex.

I gutted the sport body of all its accessories, and I have proline hyrax tires on it with knockoff vanquish 1.9's..

Currently using shorty packs, ( 4600 shorty 3s)



Thanks
-Spence

 

[AnimalHippie]

New lighter body

lcg battery tray, front tray doesn't allow for big enough battery for me.

Alloy axle housings. I only did the front

A good set of foams or anti foams

Metal beadlock wheels

Good luck!!! These rigs are awesome!!! I love mine!!!

 

[Ninomaniac]

Definitely need to bring the battery lower or up front. I have my ESC on the front on the bumper mounts, Rx (and shift servo, I added 2 speed) on one side, battery on the other. Lower the body as much as possible. You don't need more flex. With all the brass you have, that's pretty much it aside from swapping everything over to a LCG chassis.

Oh and I added some O rings below the piston to reduce shock travel, so I can run less preload without the springs falling out of the lower perches. Travel is almost same, ride height is a mm or two lower.

Good foams like AnimalHippie said, the tire looking aired down may be cool but doesn't do much for sidehill stability or performance overall.

 

[MOguy]

If your goal is performance and performance is your goal below are my suggestions. If you like accessories or more scale than use this as a guide line. There are no right or wrong answers just trade offs.

Get rid of every ounce you can everywhere you can get rid of it, that means EVERY OUNCE ADD NOTHING!!!!!!!!!! You should be left with nothing but rails and MINIMAL plastics just to hold things on and together. Take you side skids/rocker guards and make them just big enough to you mount your ESC, battery ad receiver too. Ditch the big receiver box. Get a Dremel and go to town! Smooth dow your side skids as flat as you can.

If you need a specific battery mount you battery is too big. You should use a battery small enough you can hold it ow with Velcro. You ca use a zip tie or Velcro straps to keep it it place. BowHouse has a transmission skid that will set your transmission lower. Get some aluminum shock mounts (mount your shocks higher and rear slightly forward). Mounting your shocks higher lowers your weight, mounting it forward a little will let the shock move better for more travel.

Overdrive in the front, maybe underdrive rear.

Raise you rear upper links on the transmission side, this helps with climbing ad control.

You need stiff sidewalls ad soft tread area. You deal with this in the tires and foams.

Mount everything ESC, battery, receiver as low and far forward as possible.

Mount you body as low as possible, send the shock tower through the body if you can. JC Concept bodies are light, get one of the those. The pick up style, such as a creep will keep weight lower. If you use a SUV type, mount it even lower.

Get rid of EVERY OUNCE YOU CAN!!!!!!!! Gravity is the enemy!

You want your weight about 60% bias toward the front and equal side to side. Add back weight on your axle to achieve this. Vanquish and SSD sells 4 ounce brass rings to but in your wheel but you have to have the right wheel. You can also get weighted diff covers, axles or what ever.

Adding back weight should be the LAST thing you do, the very last, everything else should come first, everything else. Adding weight is the last thing you do.

Gravity is the enemy. It will pull you down no matter what. You are fighting gravity and weight is the enemy.

TRX axles area heavy, the are strong, they work in the stock form. Don't waste money on metal axles.

Gravity is the enemy, more weight makes gravity more of an issue.

 

[ferp420]

there are 2 basic.schools of thought when it comes to rc crawlers theres the scaler side and the comp side

scale rigs we usualy add weight to get more bite from the tires
comp rigs are light so theres less gravity to fight

tires will likely make a huge differance as will whats inside the tires

if your doing alot of side hilling stay away from over/under drive gears they kill.the side hill but can help in your climbs i personaly dont under/over drive my scalers

for the op i would sugest removing some weight in the rear and leave the front as is

personaly for my crawlers i like a 70/30 weight bias but that makes down hills harder a 60/40 split is a good start and you can tune from there its always a.ballance between up hill performance and down hill.control

 

[MOguy]

Another thing to consider is selectable lockers. But the OP has a sport.

Unlocking the front lockers helps with sidehill. Set like that cause power to follow the path of least resistance. That will be the upper tire. As it pulls from the side hill that tire will spin. When it comes down it will bull the RC back up the side hill.

Unlocking the rear helps with climbing. Set like that cause power to follow the path of least resistance. Having the diff open the rear tire with less weight and traction will spin and allow the front tires to pull you up with out the rear tires flipping you but if it all of a sudden itget traction it will flip you.

 

[themountain]

Well....weight reduction is only helpful to a certain degree...too light your rig wont have no useful traction. More important is the distribution of it...60/40% is a good start. The Trx4 suffers a bit with steering angle....so thats one thing I would look at. Droop in the suspension is another thing.

 

[MOguy]

Well....weight reduction is only helpful to a certain degree...too light your rig wont have no useful traction. More important is the distribution of it...60/40% is a good start. The Trx4 suffers a bit with steering angle....so thats one thing I would look at. Droop in the suspension is another thing.

Too light for climbing up steep stuff possible but not on side hill.

BUT the TRX has much heavier axles and transmission than other so not sure if you could get a TRX too light, maybe?

Steering is an issue but you can file a little off the hubs and knuckles and a bit of positive caster helps.

As far a susp and droop? Just depends on what people do to get "droop".

 

[Spence]

Thanks guys for all the replies! I forgot to mention the metal knockoff vanquish wheels and hyrax, and use of shorty 3s packs in addition to removing all the heavy racks off the sport body, but luckily this will give me more direction to squeeze more performance out of it.. I got the sport kit cause I knew the stock electronics sucked and I wanted to build it myself and save some money as a bonus swapping premium electronics from another crawler..

 

[MOguy]

Thanks guys for all the replies! I forgot to mention the metal knockoff vanquish wheels and hyrax, and use of shorty 3s packs in addition to removing all the heavy racks off the sport body, but luckily this will give me more direction to squeeze more performance out of it.. I got the sport kit cause I knew the stock electronics sucked and I wanted to build it myself and save some money as a bonus swapping premium electronics from another crawler..

Hyrax G8 or predators? What foams?

 

[Spence]

Hyrax G8 or predators? What foams?

Eh theyre nothing special, just stock hyrax g8 with stock foams, eventually gonna get some crazy crawler foams

 

[MOguy]

Eh theyre nothing special, just stock hyrax g8 with stock foams, eventually gonna get some crazy crawler foams

If you stay light that set up will be fine for a while. The tires will soften, and the foam will break down. At that point the tires will work better but the foam will collapse more for the side hill. I have crazy crawler HD in my predator compound and going to try their basic in my G8s. My Rc that they will be in is about 5Lbs 10 ounces.