Common Scaler Crawler Setup Mistakes

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Nobody likes making mistakes. If you’re participating in scale comps, mistakes will, of course, keep you from succeeding. Now, the old saying is it’s smart to learn from your mistakes. Well, I think that’s true, but I think it’s brilliant to learn from other people’s mistakes, so below are the top five mistakes people are making with their scale crawlers.

losi comp crawler performance

TOO MUCH ARTICULATION
This might be the most common setup mistake crawlers make (or maybe I just think it is because people love to show it off), and it has been an oft-made mistake as long as RC crawling has existed. It’s pretty obvious that articulation or suspension flex allows you to travel over rough terrain without the tires losing contact with the ground. To many people, it also simply looks cool. Flex is good, so more flex must be better, right? You may have guessed that the answer is actually no. Too much articulation allows a vehicle to get all twisted and bound up in difficult situations. Read the section on soft suspensions to see what happens and why. Most–but not all–setups that deliver tremendous flex also deliver excessive axle steer. Axle steer is when the axle (front or rear) moves in a front to back arc as it articulates (the truck crabwalks). The end result is unpredictable handling, which is far worse of a problem than having to hang one tire over, say, a crevasse type situation.

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SUSPENSION TOO SOFT
This goes hand and hand with too much articulation, but must be handled separately. Why is too soft not too good? Think of all that torque your motor makes like it’s water flowing downhill–it takes the path of least resistant. So, if a tire is bound up, it will transfer that twisting power to the soft suspension. This usually happens when the rear tires are up against a ledge. Instead of putting power t the ground, the tires lock in place and the suspension starts twisting and squashing down. In general, you can get away with a softer front suspension. In fact, many experienced tuners setup the rear suspension a little firmer than the front. Axial offers different rate srpings for its scale shocks, so there is no reason to be stuck with the stock rate. The optional springs are great for tuning, of course, but you may also need to go to a stiffer rate to account for a heavier than stock vehicle after you accessorize your RC truck.

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WRONG TIRES
You can get a lot of bad advice online. That might seem like kind of an odd thing to say on an online media outlet, but it’s so very true. Some of the worst advice I see dished out involves tires. Just because little Timmy says his tires are great doesn’t mean that he isn’t simply biased towards what he owns. Little Timmy might say tires from brand X rule, but we don’t even know if he really has anything to compare them to. Take advice you hear online about specific tires with that proverbial grain of salt. If you crawl in comps or with a club, watch the other trucks and see what works. But, don’t just watch, listen. Tires that grip, don’t chirp and spin on the rocks. If you don’t crawl with other people check out these tire reviews:

scalerulesopener

POORLY PLACED SCALE ACCESSORIES
If you’re going to add them, consider how their placement will impact your vehicle’s center of gravity. A roof rack is the easiest place to add scale accessories and, of course, the worse. Resist the temptation to add every scale doodad you can think of to the roof rack. Keep scale accessories to a minimum and keep them low. If you run a full spare, don’t use memory foam in it. Look, you’re not really going to get a flat and memory foam weighs a heck of a lot more than standard foam.

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WRONG POWER SYSTEM
Adding a powerful system isn’t as straightforward as many people think, so just as many people end up getting it wrong when picking out new gear. Think of a power system as a four part system—motor, speed control, battery and gearing.

The motor is the first piece people think to replace in the search for more power. Going with a higher Kv brushless system or a lower turn brushed motor means more power that will deliver the wheel speed that is all the buzz. Contrary to conventional wisdom, go with a low Kv motor and try to find a 4-pole motor. The 4-pole design will make more torque and run cooler. If can’t find a 4-pole, it’s okay as the main goal is to keep the Kv low. Also, if you’re going brushless, you have to go sensored–end of story.

For a speed control, make sure it has the ability to offer instant reverse and has adjustable (and strong drag brakes). I see a lot of people with waterproof systems (usually borrowed from a Traxxas vehicle in their fleet) and while I love waterproof electronics, I wouldn’t give up instant reverse and drag brakes for waterproofing, so make sure the system you select has these crawling essential features. Factory BEC specifications are getting better, but I still suggest installing a Castle Creations CC BEC. The last must have feature is the ability to handle 3- or 4S LiPo packs. High voltage is the place to get power, don’t high Kv motors.

As I said above, I think of the battery as my real source of power, not my motor selection. While I don’t exclusively use MaxAmps.com batteries, I do these often because, while they do cost more, the quality is good and they are guaranteed waterproof. While I still run 2S packs in plenty of my rigs, a winning comp setup uses a 4S setup.

With a 4S battery sending all that juice to your motor, you can get away with some low, stump pulling gearing. It’s nice to have wheel speed when you need it, but torque still gets 90% of the work done. Gear low and crawl. Squeeze the trigger and enjoy that 4S lighting up your tires when needed. Added bonus, the low gears, high voltage and low Kv combination will run cool and last a long time.

Links
Axial Racing
Castle Creations
Pit Bull Tires
Pro-Line Racing
MaxAmps.com
Traxxas

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Filed Under: FeaturedRock Crawlers and ScaleTech

Matt Higgins About the Author: Matt has over 25 years of experience in RC and has worked professionally in media for over a decade. Matt enjoys everything from racing to rock crawling to bashing, and he believes RC should be all about having fun. Matt is as at home covering a world championship in an exotic country as he is showing a new hobbyist how to set gear mesh. His desire to share the hobby with as many people as possible inspired him to create RC Truck Stop and RCTruckStop.com.

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  1. Ryan D says:

    despite contrary belief Lipo are inherently waterproof regardless of cost or marketing, all lipo have to be airtight or they burn, airtight is also what? you guessed it, WATERPROOF…

    • Matt Higgins Matt Higgins says:

      Ryan, not sure I 100% agree. The cells have exposed metal tabs that the leads are soldered to. It is my understanding that the MaxAmp.com packs are sealed so that the tabs are not exposed, so I still personally prefer MaxAxmps.com packs for vehicles that see water. Odds are almost all LiPos can handle a dunking, but there is nothing wrong with going with the packs that guarantee that they are waterproof

      • Josh Barker says:

        Your explanation pretty much hit the nail on the head. Internally the cell is water proof. The exposed tabs however are the concern. Depending on mineral content and wiring (i.e. some packs have tabs to soldered together via a PC board) these tabs can short when introduced to water destroying the pack. If the cell does hold up and does not short the next enemy is then rust and corrosion which will cause tabs to break free of the cell, or wires from the tab, or at the very least increase resistance in the pack over time. I can tell you that if you buy a pack from just about any other company and the pack has gotten wet and failed it is not covered under warranty. We remove that issue from the equation and protect your pack for the long haul. Our packs last longer, run stronger, and are used in more applications than pretty much any other brand.

  2. Daniel Siegl says:

    Hi Matt,

    Excellent!

    Cheers
    Daniel

  3. Adrian says:

    Hi Matt!

    Thanks for this article!

    In 4 of 5 points I’ll agree for 100 percent. At the moment I run with 3S and I like it so far – but I think a have to try 4S in the future :-)

    Thanks and greets,

    Adrian

    • Matt Higgins Matt Higgins says:

      Thanks for checking out the article and commenting, Adrian. I’d say the vast majority of people still run 2S, so you’re already ahead of the curve. Sounds like you know what you’re doing. If you go 4S, I really encourage you to install a smaller pinion and lower Kv sensored brushless motor. You’ll love the setup. It will be a powerhouse of speed and torque, but will run cool and stress free if you get the gearing right. Thanks again!

      • JohnK says:

        I run a 3S in my F250 Scaler, components are up front under the “hood” that are open to air, but surrounded so splash water can not get to it…its a Axial based rig. Not worried about water, I can go to over the wheel wells 3 1/2-4″. My Scout Scaler is Axial axles and a summit two speed tranny with 4S. Electronics are in a sealed box in the front and battery is in the “tool box” in the back…water can get up to just the top of the doors. My point is that you can run Lipos that are not “waterproof” and still run in water…just protect them…I have seen some of them wrapped in a balloon..Not sure if I agree with that.

        • Matt Higgins Matt Higgins says:

          Of course, John. I’ve seen plenty of scaler take on mud and water with LiPo brands other than MaxAmps.com. I was just explaining why I prefer them. Thanks for visiting RC Truck Stop and checking out the article. And, thanks for commenting.

  4. Chris M says:

    Great Article Matt, really hit the nail on the head !!!

  5. gery says:

    Hello Matt, great article. Would love to translate the article into German and publish it on my German language blog http://www.rc-modellbau-blog.com. Therefore, I ask for permission to do so. THANK YOU

  6. Nick says:

    Thanks Matt! This is a great and concise list of to-do’s when starting out with crawling. I learned a lot during my first comp last year here in Utah and your article backs those up and helps me keep the focus, and money 😉 on improving things that really matter.

  7. Jim says:

    great advice, i shall consider this on my rig

  8. pete says:

    Hi matt. I totally agree. I’ve been using 3s for a few years now and just got my first 4s capable brush less setup. It awesome!

  9. Zach G. says:

    Hey Matt,

    Still running 2S in my Honcho, but I agree that I do need a little bit more power, now I’m not sure about a 4S, but I would consider a 3S and a slightly different motor setup, if I could waterproof it myself, or it already came waterproof.

    The batteries point is spot on with the water situation, because after I dunked my 2S Hobby People LiPo in a creek, it didn’t really deliver the same power afterward it seemed.

    Thanks for the setup advice, I will put your points to good use…

  10. perry says:

    Thanks for the article Matt. A lot of this has parallels in the 1:1 crawling scene as well, which I think sometimes is so obvious we overlook it. I just got my first crawler, and after having over 25 years in and around r/c, this is the most fun I’ve had with it in a long time.

    Very well written article.

  11. pfuture says:

    Last year my truck had bad handling and everyone was used to see my truck fall on its top in various places. Suspension was too soft. I still use the stock shocks and springs but the shock collar is now down by about 6mm. My truck is almost like another truck. I have more signs before it tips over and it takes much more before it wants to tip over.

    Concerning tires, i don’t know it if’s just me… But they seem to have gotten better now that they have been driven for hundreds of kilometers.

    Good advice, thanks for this article!

  12. Mike "WildMan" says:

    Hey Matt, love the article. I pretty much agree with everything mentioned. I totally agree about the tires. I have been 1:1 crawling for over 15 years and 1:10 scale crawling for the past 5. I think one thing that could have been mentioned about the tires is the fact that what works great for Johnny in the western terrains are not necessarily going to perform as well for Tom or Timmy in the mid-west or east coast terrains. There is also different tread patterns and compounds for many different types of terrains. I, as a 1:1 crawler, used and was very much waiting for the one tire you mentioned to come on scene for the scalers and was so excited to see it when it did. To me, one of the overall best for the biggest range of terrains. I am not stating which one simply because I want people to form their own opinion on which is the best instead of reading it from me or anyone else for that matter. Happy Trailing/Crawling

    • Matt Higgins Matt Higgins says:

      Awesome points! Thanks for visiting and commenting, Mike. I often make that very point about racing tires (what won the Nationals at one track may just spin out at a different track), but it is just as true and worth mentioning when it comes to the rocks.

  13. fadi says:

    Hi matt. Very good article..i have a rc4wd gelande 2. Which is veery heavy. So i lack tourque.. i have a 45t motor.. 4200 mah battery. And a waterproof hpi esc with medium drag brake.. so sometimes i cant go up the hill..i have the same setup on the lighter trail finder but it goes very good on low gear.. on g2 no…Where is my problem matt.. thanx in advance

    • Matt Higgins Matt Higgins says:

      Assuming there is nothing mechanically awry causing the problem, I would suggest a 55-turn brushed motor or equivalent brushless setup matched with a 3-cell LiPo pack. Further match that with a small pinion. I personally like the pinion to be just big enough that the wheel speed is such that if I grab full throttle suddenly, the tires will break loose on loose dirt. Hope this helps.

  14. JBH says:

    Hey Matt,
    I have a an Axial Dingo. I crawl with a local club and always end up last. The cars in my club are fairly tricked out where as mine is fairly custom. I’ve cut back the body, cut parts of the bumper for better approaches/exits, put in 4 link on the front and back, etc. But everyone tells me I need new (i.e. larger outer diameter) tires. I am thinking of purchasing the JConcepts Scorpios 1.9 All-Terrain as they have an o.d. of 4.75 inches. Much better than my stock ripsaws. What are your thoughts on this?
    Second, I seem to remember in my RC days of long ago reading about how if the shocks are angled as opposed to linear, it will actually give my axles better/more travel without raising the height too much if at all. Is this true? If so, I had thought about moving my shocks down and into the center of the car more. Would this be a good move? I’m trying to think of things I can do to improve with out spending a ton of cash. I don’t need to win, jut not come in last :) Thanks for the help and the great article!

    • JBH says:

      Sorry, I meant to say mine is fairly stock, not custom!

    • Matt Higgins Matt Higgins says:

      You’re going to win. We’ll figure this out.

      First, upgrading tires is never going to hurt. Other than your driving, tires are the most important element. Whether we’re talking NASCAR or RC crawlers, tires are super important.

      We need to know a little more about why you’re not claiming victory (yet). Are you having a hard time with gates and boundaries or is the truck struggling on obstacles? Are the people winning just marching up stuff your truck struggles with or is your truck too hard to get through gates without hitting stuff?

      Shock angles are not the issue. Getting the truck’s CG low while increasing ground clearance. So, yes, get taller, softer and stickier tires, run memory foam, add weight to front and then lower that truck down.

  15. Rajiv says:

    Greqt article mate. Will be sharing it with my rc club out here in london.

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