Why can't a crawler also be genuinely fast?

[CoupeUK]

2sp TRX4
Unlocked diffs
Holmes BRXL
Holmes Trail master Sport 21t
6s lipo

That should give you plenty enough speed!

[BP6666VR]

Originally Posted by BP6666VR

Would this work for you ? 50 mph crawler ?

Hobby Wing Fusion Pro

https://youtu.be/v0f7rcyO0Ds

How awesome slow is that in second gear ......

150 $

Motor & ESC in one, so can submurge in water no problem

What gearbox would fit best on that ?

Click here https://www.amainhobbies.com/hobbywi...2885_d2baf9029

Sent from my CPH1937 using Tapatalk

Nobody have this Hobbywing Fusion Pro in there builds ? Seems a very good option for a custom build crawler that is slow & fast at the same time ?

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[MOguy]

Originally Posted by BP6666VR

Nobody have this Hobbywing Fusion Pro in there builds ? Seems a very good option for a custom build crawler that is slow & fast at the same time ?

Sent from my CPH1937 using Tapatalk

Way too heavy for a crawler I would build, and at speed I can't imagine a soft crawler susp being able to maintain any control. But if it may be a good choice if you want a fast and slow motor but I just see too many other things that need to happen in a crawler vs. a speed machine.

[bgredjeep]

My bomber is pretty fast. The trouble comes when you hold full throttle for more than a second or 2. Maintaining control at high speed is very different than having a car that can go fast. Mine does ok as long as I slow way down before any attempts to turn.

[TooOldForThis]

I've toyed around with some fast crawlers, mostly because I'd love a nice scale pre-runner style truck that could move at a good pace, but the suspension and handling always kills it. Locked diffs don't mix well with speed, and even if you can unlock them in something like a TRX4 you're left with suspension that can't soak up the bumps very well, and even if you avoid bumps you still have the problem of rolling easily while turning. First company to come up with a solution to this gets ALL of my money, especially if it involved a nice scale I-beam suspension, but until then the best way to scratch the scale speed itch is with something like a Baja Rey or Traxxas UDR.

RC brands, if you're out there, gimme this in about 1/9 scale. Pretty please.

[OSRC]

I've posted this around, though never bothered with a build thread. It's a TRX chassis with open diff SCX10 axles and a Castle 3800 4 pole. Lower CG than the portals, the high ratio of the trans made it a perfect "go fast" truck. It flat hauled in a straight line (40mph ish), but turning at anything even close to 40% top speed was an immediate barrel roll. I used harder tires to try and help - not so much. Tried a much stiffer suspension and it still wanted to roll - COG is just too high.



This was a 1 trick pony though, with the open diffs and taller gearing, crawling was completely out.

Open diffs in a Wraith? Worked out pretty well. I think if your're going to have any speed and handling at all, open diffs is a must.

[Speedy-Triple]

anything with a front straight axle wont be good for speed ... no matter how tuned the suspension is way too unstable at high speed creating transfer forces that end up moving the rear end with any input from the road (we want whoops right - not talking about flat ground) Reason why all well built pre-runners and trophy trucks use IFS or I-Beam set ups to soak the front travel adequately keeping the rear end stable and straight which equals traction. Unfortunately IFS is and speed means low and slung for performance anb this is obviously a detriment for crawling where ground clearance and articulation is key. U4racing rock buggies are getting real close to this level of performance though, although i am not a fan of the look TBH.

[Sweetride95]

Originally Posted by Speedy-Triple

anything with a front straight axle wont be good for speed ... no matter how tuned the suspension is way too unstable at high speed creating transfer forces that end up moving the rear end with any input from the road (we want whoops right - not talking about flat ground) Reason why all well built pre-runners and trophy trucks use IFS or I-Beam set ups to soak the front travel adequately keeping the rear end stable and straight which equals traction. Unfortunately IFS is and speed means low and slung for performance anb this is obviously a detriment for crawling where ground clearance and articulation is key. U4racing rock buggies are getting real close to this level of performance though, although i am not a fan of the look TBH.

This.

[TooOldForThis]

Originally Posted by Speedy-Triple

anything with a front straight axle wont be good for speed ... no matter how tuned the suspension is way too unstable at high speed creating transfer forces that end up moving the rear end with any input from the road (we want whoops right - not talking about flat ground) Reason why all well built pre-runners and trophy trucks use IFS or I-Beam set ups to soak the front travel adequately keeping the rear end stable and straight which equals traction. Unfortunately IFS is and speed means low and slung for performance anb this is obviously a detriment for crawling where ground clearance and articulation is key. U4racing rock buggies are getting real close to this level of performance though, although i am not a fan of the look TBH.

Agreed. Last fast crawler I attempted was a Gatekeeper converted to IFS. I thought between the IFS and the rear sway bar it would be an improvement over other things I tried, and it was, but it's really top-heavy and still had locked diffs. This might be a stupid question but does anyone know if open diffs are available for the Element trucks? They wouldn't fix the top-heavy issue but the other handling characteristics might not be that bad if the diffs were open. It would kinda be like a narrow Rock Rey.

[OSRC]

Originally Posted by TooOldForThis

This might be a stupid question but does anyone know if open diffs are available for the Element trucks?

No, not that I am aware of.

I use SCX10 V1, AR60, Wheely King, or TRX4 axles if I need an open diff. There are probably a few chinese brands out there that can be used, but I have no idea what they are offhand.

[ferp420]

i took a yeti and streached it about a foot its a good trail truck it dose crawl and it dose haul but it is a ifs with open front diff and slightly overdriven up front to keep it in a straight line when its hauling its
on the rocks it takes some work you have to pick and choose your line but it makes it just about everywere my other 1.9 rigs go but i wouldent call it a crawler

something to think about at.the king of the hammers the bomber is still the most used chassie out there and its won alot of races
those bombers are.still hitting close to 200mph out there on the lake bed so i wouldent say a solid axled rig cant go fast off road they do all the time

[Speedy-Triple]

Originally Posted by ferp420

i took a yeti and streached it about a foot its a good trail truck it dose crawl and it dose haul but it is a ifs with open front diff and slightly overdriven up front to keep it in a straight line when its hauling its
on the rocks it takes some work you have to pick and choose your line but it makes it just about everywere my other 1.9 rigs go but i wouldent call it a crawler

something to think about at.the king of the hammers the bomber is still the most used chassie out there and its won alot of races
those bombers are.still hitting close to 200mph out there on the lake bed so i wouldent say a solid axled rig cant go fast off road they do all the time

you said ... it ON THE LAKE BED. if im thinking off road on a Built Rig im taking the less traveled road and hit the whoops.

[MOguy]

You can't compare a King of the hammers race vehicle that cost hundreds of thousands of dollars to an RC car that cost maybe a grand or so.

Even then the best King of the hammers race car will not crawl as good as the best crawler. It will not go as fast as the fastest sand car.

You can't have it all. You can only have a compromise.


Compromising may be perfect, depending on your goal.I have a fast Wraith that's a compromise build and it's a shitload of fun I love Hill racing it. I never win, I might not even finish but I have a shitload of fun. If I tried crawling it may be fun until I get to the first gate but I probably won't even make it through first gate, depending on the course.

I got to use tx4 for the granddaughter altogether I'm in it less than 300 bucks. I got a arrma granite for 150 bucks used. The electronics is my fast Wraith cost more than both those cars combined but The Wraith will not crawl as good as a trx4 or go as fast and handle as well as the granite.

[JohnRobHolmes]

The electronics are constantly improving delivery of slow + fast in the same package. It is still a tradeoff on power draw and efficiency at slow speed vs high speed. Just like the suspension tuning, its always jack of all master of none situation.

[lonleycreeper]

Originally Posted by JohnRobHolmes

The electronics are constantly improving delivery of slow + fast in the same package. It is still a tradeoff on power draw and efficiency at slow speed vs high speed. Just like the suspension tuning, its always jack of all master of none situation.

This is the first post I have seen from the Motor Master himself...WELCOME BACK MR. HOLMES!

[ferp420]

Originally Posted by Speedy-Triple

you said ... it ON THE LAKE BED. if im thinking off road on a Built Rig im taking the less traveled road and hit the whoops.

i here ya even with a mildly built rig even



at the end of the video is part of the race course in a station wagon

https://youtu.be/K9s4yyCpfCQ

[ferp420]

Originally Posted by MOguy

You can't compare a King of the hammers race vehicle that cost hundreds of thousands of dollars to an RC car that cost maybe a grand or so.

why not the bomber is literally a scale replica of the bomber that won king of the hammers what how many times by how many different drivers

Even then the best King of the hammers race car will not crawl as good as the best crawler. It will not go as fast as the fastest sand car.

You can't have it all. You can only have a compromise.

i agree but how good dose it have to crawl to be a crawler and or how fast dose it have to be to be fast

[fyrstormer]

Originally Posted by ferp420

why not the bomber is literally a scale replica of the bomber that won king of the hammers what how many times by how many different drivers

Because physics doesn't scale linearly. The fact that the Bomber is the same shape doesn't mean it behaves the same. It doesn't have the same center of gravity, the same moment of inertia, the same chassis flex, the same power-to-weight ratio, the same traction-to-weight ratio, the same torque curve, or the same obstacles to climb over.

[ferp420]

Originally Posted by fyrstormer

Because physics doesn't scale linearly. The fact that the Bomber is the same shape doesn't mean it behaves the same. It doesn't have the same center of gravity, the same moment of inertia, the same chassis flex, the same power-to-weight ratio, the same traction-to-weight ratio, the same torque curve, or the same obstacles to climb over.

what ? are getting all scientific on me

in my opinion its close enuff for all practical purposes

i dont know about you but i litterally run on the same terrain as the 1:1 bombers and yes we do have scale woops as well

[TooOldForThis]

On the topic of this thread, the Monthly Mayhem speed challenge videos are dropping. This was a really cool collaboration I hope they do more of. So creative and fun.

https://harleydesigns.com/monthly-ma...peed-challenge