OS's TRX4 Sport Kit

[OSRC]

Other TRX4 Builds:
Defender
Bronco

Overview:


A Traxxas kit. Who would have seen that one coming.


As a guy who prefer to build kits, I had to order one just to see what a Traxxas kit was like. Turns out it was pretty nice! Jato is doing a good job posting details of the build, so no need to re-hash that. Will add a few thoughts:

• If you've never built a kit, this would be a great one to start with. Good instructions (full color - nice!) and the links and shocks are already assembled. Took me about 3 hours total to build. All parts were nicely orgainzed, well finished (no flashing or anything) and it went together flawlessly.
• The body is cut and drilled. Good and bad...good in that it's prefectly done and one less thing to do, bad in that I wasn't planning on running the rear cage, but all the holes are already drilled. The headlights and tailights were already chromed inside the buckets, though molded in black. Again, the details are well thought out in this kit.
• Traxxas already has threadlock on the screws where needed - nice touch! Again, attention to detail.
• It's an easy to build kit, but the axles have a TON of screws. All those portal screws add up...make sure you eat your Wheaties the morning you asemble it.

So anyway, it's a very nice kit. Pleasure to build.

Now that that's out of the way, Jato and I go wheeling and we've agreed to a little build off of sorts. We're starting as stock as possible and heading out for a run to compare and get a baseline. Difference being our electronics - mine is distinctly budget friendly and he's got a higher end setup. Then we'll do some chassis mods within a certain budget, and then go for a second comparison run to see what works.

Really it's just an excuse play with trucks.

Anyway, here it is built. Stock chassis and setup mostly, we agreed on swapping in beadlocks ilo glue-on wheels, though the tires and foams are stock. Waiting on the motor and servo to arrive.

Gotta say I like the Sport body much better in person than I do in pics. Fender flares look great and the light buckets are very nice as well. About as good as it gets for an unlicensed body.

[Topher Builds]

Love the wheel choice. I agree that the body is appealing in person.

Looking forward to seeing both the builds

[soze]

Nice! Can't wait to see it finished!

[OSRC]

Motor arrived today. I thought I had ordered a Holmes 21t sport, but apparently I clicked on the 45t instead. Whoops! Not sure if that's going to work... Since we're planning on wheeling this weekend, I need a plan B!

Good news is it's painted already. Just got to get to the details.

[JatoTheRipper]

The wheels are awesome. I almost ordered a set of those Fachetes, but I have so many new and used sets of 1.9s lying around at home that it would have been foolish of me to buy more wheels! Not that I've never made foolish purchases before.

You gotta finish electronics and I gotta finish paint and then we're ready. I can't wait! At this point it looks like it should be a good weekend for trailing.

[OSRC]

Well, I thought I had ordered a Holmes 21t 550, but I somehow ended up clicking the 45T. Whoops! I'll use it somewhere, but not here. Not quite enough RPM...so I need a plan B.


Plan B. I have an old Kyosho 22t 550 laying around. It's only been run once or twice. It'll do for now! Set up the gearing at 15/45 to get started. Subject to change of course!


Electronics in..left the wires nice and long in case I decide to change up something later. Said used motor, WP1080 and an Hobbyking HK15298B servo (250oz Torque).. Total cost for electronics factoring in the motor I bought is $80. Defintely a budget setup. We'll see how it all does.




Ah...removing the overspray film from a freshly painted body. One of my favorite things to do in this hobby...


Didn't realize how many scale items are bolted to this cage. Some decent stuff here! I didn't really detail anything since I don't plan to run the cage per-se after our initial test run. Just bolted it all on for now though with a bit of detail work, should look pretty nice!


...and finished up and ready to hit the trails!





Final weight with battery comes in at 3163g (6.97 lbs) with a 51/49% front weight bias. Kinda surprised at that, figured with all that weight out back on the cage it would be rear heavy, but apparently not.

Gotta give props to Traxxas... I picked up this kit for $254 shipped. Metal gears all around, metal servo horn, metal links and pivots, excellent shocks, a decent (if unlicensed) body with light buckets and a ton of scale details. Very solid when built... I'm no Traxxas fanboy, but frankly, it's a tough deal to beat. Can't wait to get it dirty!

[meatmonkey]

That sweet magnetic mayhem has some non-adjustable timing built into it. I only know this because I have the "reverse rotation" version for my regular kit version. If your crafty you can manipulate the end crimping to free the endbell and install a locking ring with regular screws and recrimp to make motor serviceable and adjust timing to allow it to live long and prosper.

Otherwise, build looks good. No inner fenders included, correct?

[soze]

Looks great! 2 of my favorite colors!

[JDM74]

For an unlicensed body, that thing looks pretty dang good. I like what you did to the grill. Great color choice.

[B-MOW71]

Great job on the paint. Love the colors. I like the fender flare bolt idea that you painted on it.

I was one of the Sport body haters when they first came out. But after seeing many cool paint schemes with clear windows I picked one up for my TRX-4 Kit. Love the body now and it does really well on the rocks.

Looking forward to seeing more pics.

[JatoTheRipper]

I hope my paint turns out that well! It looks great.

So we can change gearing? I forgot what we agreed upon. LOL

[kincer]

Another great looking Sport body! I can't believe how much better they look over the RTR versions.

[rattmobbins]

Way cool looking paint scheme! Totally agree the Sport body looks MUCH better in person and with some scale details added. I have 3 bodies, all with different configurations. Lol

[OSRC]

Originally Posted by meatmonkey

If your crafty you can manipulate the end crimping to free the endbell and install a locking ring with regular screws and recrimp to make motor serviceable and adjust timing to allow it to live long and prosper.

Otherwise, build looks good. No inner fenders included, correct?

This is the regular rotation version..I did monkey with it to get to zero timing. At least I think so, I don't have any way to test per-se, so I did an "ear tune." Think it's good to go. Only has to last one run though, I've got a replacement in mind.

Originally Posted by JatoTheRipper

I hope my paint turns out that well! It looks great.

So we can change gearing? I forgot what we agreed upon. LOL

Don't ever buy the blue "edge lock" tape - it's terrible. Lifting constantly, and lots of bleed though. At the edges of all places. Very disappointed in how the paint came out. It's a 10- footer for sure. The standard tape works so much better.

I wasn't planning on changing the gearing, but when building the kit the slipper pads are stick on - wasn't going to stick them on a spur gear I'll never use again. Feel free to re-gear as needed! I would think your power system will have no trouble moving the truck with the stock gearing however. My brushed system might need a little help.

[JatoTheRipper]

Originally Posted by OSRC

Don't ever buy the blue "edge lock" tape - it's terrible. Lifting constantly, and lots of bleed though. At the edges of all places. Very disappointed in how the paint came out. It's a 10- footer for sure. The standard tape works so much better.

I wasn't planning on changing the gearing, but when building the kit the slipper pads are stick on - wasn't going to stick them on a spur gear I'll never use again. Feel free to re-gear as needed! I would think your power system will have no trouble moving the truck with the stock gearing however. My brushed system might need a little help.

That's a bummer. Thanks for the tip.

You know I do now remember us talking about you changing gearing. Sorry!

I think I will change gearing eventually as well just because the truck is fast as-is. But with the ESC settings and the motor it's still really controllable so I'll see how it does on the trail run before making any changes.

[OSRC]

Decided to make some motor changes before heading out. I tuned around on the timing as best as I could on the Magnetic Mayhem, but wasn't convinced I had gotten to zero timing. Instead of possibly wrecking this motor, I decided to see what else I had. Found a Mabuchi 5 slot 550, and a larger 560 motor in my stash. The bigger motor didn't fit, and the 5 slot was just too slow. Super smooth, but very low RPM. 80t maybe? IDK. I did find a new reverse rotation E-maxx motor that did work out though - pretty much the same as stock, so in it went.


No bullet connectors means changing motors is a bit complicated.


E-maxx motor now put to good use!


Out on the test course in the back yard...just setting the steering trims and ESC settings. I remove all the punch for a soft throttle tip-in, and set the drag brake to about 50%. Let's play!


Stock tires rub the fenders under compression just a touch. Nothing a little scissors work won't cure.


In 10 minutes of testing, I was proven wrong. I expected a rollover queen with a somewhat high COG, but the Sport was surprisingly sure-footed.


All that weight on the rear with the cage and scale stuff does affect climbing ability, but it's very manageable. Gives you plenty of notice before calling it quits.


On steep climbs, the rear suspension compresses and you get some 3 wheel action. I think the stock suspension is a bit on the soft side - almost has too much flex. Time will tell...


Testing's over, let's head out to a trail.

[OSRC]

Met up with Jato at out St. Pete's (crawler heaven) for a few hours of playtime on Sunday. Trucks were box stock, though I was running brushed/WP1080 and he was running a Holmes outrunner/Castle ESC.


Honestly, I felt we had comparable power. His truck was a bit faster in a straight line, but mine seemed smoother on the low end. Really, the power in both trucks was a non-issue - don't think it helped or hindered in any way really. I was very happy with my cheap set-up...smooth, controllable, and quiet. I will say that the outrunner motor is loud. It was like driving with a dental drill all day. My older outrunner motor makes noise, but nothing like that. I believe his throttle curve had a ton of expo IIRC so it spent a lot of time at very low RPM.


So anyway, I felt that the Sport would do pretty good just based on testing in the backyard, and even box-stock it did not disappoint. Hit all of our usual test rocks to compare to our other rigs...this is a tricky side hill line and as long as you took your time and let the truck plant itself, it was very capable




Simple off camber incline with a progressive incline...most of my trucks can get up here with a bit of patience, though the Sport just could not do it. Wanted to pull the front wheels up. I think without the cage out back, it would have pulled it off. The suspension out of the box is quite soft, and it wallows around somewhat.. good thing is it's very predictable. You can wheel right up to that edge of failure and ride that fine line pretty easily.


Enough with the raw crawling, let's get on the trail. No surprises here, the Sport is a great trail truck. The soft suspension that hinders it on climbs works much better out in the wild. The suspension is quite active and it's stable and surefooted. Plus all the clearance underneath makes short work of roots, rocks, and just about anything the trail throws at it.


Stock tires were pretty good, even with the stock foams. I was impressed actually. I think the lighter weight of the sport compared to the other models makes a lot of difference. Not comp tires certainly, but very decent. If I didn't have another set ready to go on, I'd have no qualms about running these for a while.


Back at the truck...ran for only about an hour but no breakage, no problems.


Now for some mods. Stock was fun, but Jato and I are going to throw some mods at out trucks and bring them back for round 2.

We decided on simple rules:

• $100 limit on chassis/suspension mods
• Stock sport body much be used, but can be modded however we like.
• Any wheels and tires we already own
• Any "free mods" are fair game.

Basically, what's the best performer we can build for an extra C note? Time to go order some goodies!

[JatoTheRipper]

You truck looks great! I had a ton of fun yesterday. I am feeling it though. Hiking through Pete's for a few hours after doing nothing for a year left me sore! Old man syndrome! Looking forward to Stage 2 of this build-off!

[Topher Builds]

Awesome stuff fellas. Enjoying watching this play out

[soze]

Nice! Both of them look great!