I did it... Dromida BX418

[Doozer]

It's been a busy two weeks, and I'm trying to finish my bipe and study. While I was in the hobby shop picking up some covering, right at the checkout sat this:



It was $99 dollars and I thought "what the hell, I'll just throw a toe in the water."  
























The chassis is plastic, shocks are plastic. The car comes with a brushed motor, a 7.2v NiMh battery, rx and controller with batteries... so it's ready to roll...somewhat...

The charge time is outrageous. It will literally be a few hours before it's actually RTR. There's only so much of that I can stand, so I purchased this:

Castle Mamba Pro with a 5300KV motor for 1/18th scale.
I had to purchase the upgrade rx from Dromida, and a 13t pinion. The are ordered and on their way. 

This is an Hyperion 3S 1100. I have 5 brand new ones that I bought for the EVA. This is how it will ride:


On a recommendation from a rc car review site, I bought some 30 wt shock oil and watched a video on how to change the oil. I opened up the front shocks and they only had a few drops in them. So I filled them. 

It's a cool toy!!

[r/c basher]

Sweet!!

When I was scrolling through this all I was thinking was you need to upgrade to a CC Mamba system. You read my mind haha! I have an 1/18 Team Associated RC18T (very similar) and I have an older version of the 1/18 Castle Mamba Brushless system you bought. On a 3s lipo it will do 50 mph, no joke! Be prepared to replace parts in the drivetrain, especially if the gears are plastic.

[Doozer]

Yep, I'm having a blast with it. You can take it anywhere. I ended up buying a FlySky GT3B controller. It was $60 bucks with shipping. I ordered a bunch of parts too. I haven't broken anything yet, but then again I'm not moving all that fast either. It's fun to jump. I know I'll see my run time go down. What size 3S lipo? I've got those 1100's, but I'm not sure they're going to give me much run time. I can almost wedge a 2200 in there, but it makes is real heavy on one side. Everything should get here at once (tomorrow). Should I get the aluminum gear? and drive train? One of the things I liked about it was that the plastic parts are dirt cheap. I really want a 1/5 scale gasser now

[r/c basher]

Good choice on the Flysky radio, thats what I use. I don't know if they offer the aluminum gear for the Dx4.18. Personally I wouldn't bother, aluminum tends to bend in a hard crash and plastic breaks. I used a 3s 2200 mah battery with mine, it barely fit. You want to watch the voltage on the lipos using the stock esc. I'm pretty sure it doesn't have a LVC since it came with a nimh battery. If the stock gears are plastic, I would upgrade them to metal or buy a lot of spares. After you install the mamba it won't take long for them to strip.

I would probably buy this-
www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXDWWB&P=ML

I would do some research though and see what other people are doing with there cars that have upgraded to brushless. Some aftermarket aluminum is too soft.

[Doozer]

ok cool. I'm not using Lipos yet... can't. Everything's still brushed until I get the Mamba. I already have a castle link programmer I used with other speed controllers (Heli), so I'll program LVC right after install. How long did you get on your 2200's?

[r/c basher]

I don't remember exactly. I'm guessing around 30 minutes?

[Doozer]

I understand that times are not a constant variable due to driving styles and such, but if you're getting 30 minutes from a 2200.... I can deal with changing out a couple of 1100's. Theoretically less weight should save rubber too. I'm going to run to the hobby shop this morning and pick up the drive train and evidently I need a new bell crank, steering linkage and a new servo mount so the brushless motor will fit. None of those things are too pricey, but now I have to get off my ass and go to the hobby store. Trips there always end up costing me more than I care to spend  

The Flysky came yesterday. Holy crap does it take a lot of batteries!!! My left forearm and bicep will be ripped in a few weeks. Who needs P90X? Wish it took a Tx pack because I have a couple of those. It does look nice though. You'd think they'd spring for a full size CD for the manual. I'm always a bit leary of the mini CD's. Also, while I have the car all opened up, I'll toss in a better servo too. I'm sure I have one laying around that is better than the stock one. However, I don't want anyone to think that this car isn't fun out of the box, because it is. I have a disease where I can't leave well enough alone, and I cause well designed products to explode from my incessant tinkering.  I'm seeking therapy

Edit: Oh btw, the mamba came yesterday too.  Shaawiiing!!!

[r/c basher]

Yeah the Flysky radio eats batteries for breakfast, thats the only bad thing. I bought 8 AA rechargeable batteries for it. The cd manual I'm pretty sure is in Chinglish. I never used the CD, I just figured everything out by playing around with it or the forums. Good idea on upgrading the servo, you'll need it with all the extra power.

[Doozer]

I'm mid mod right now.

FOR MAMBA PRO INSTALL ONLY:
To use the motor mount you'll need to modify it or find longer bolts, or use only one bolt (sketchy). I'm looking for longer bolts now, but if I need to modify the mount it will be to shave down a bolt hole.  You wont be able to mount the speed controller behind the servo as it shows in the brushless upgrade instructions on the Dromida site. You can still use the brushless servo mount, brushless linkage and brushless bell crank, but you won't need to if you modify the 2n1 case (it has the servo mount built into it). I pulled the brushed motor electronics and rx out and cut the case for motor clearance. This way you don't need to buy the brushless set up parts required (servo mount, linkage, bell crank). The speed controller will ride on top of the chassis bracket, and the rx will ride on top of the modified 2n1. I have dry fit everything including the battery and the fit is nice. I'll use 3M's Dual Lock to mount the rx and the mamba. 
==========================================================

I'll takes some pics when I'm finished. I could have bought the brushless upgrade kit Dromida sells, but I don't like the stock RTR radio all that much. It is functional, but doesn't have the range I want, and I would have to continue to use it with the Dromida upgrade kit. 

[r/c basher]

Looking forward to the pictures of it installed. I'm sure you already know this but just want to make sure, you won't need the 2in1 if you have a normal rx.

[Doozer]

Haha yep, I was just using it for the servo mount and a mount for the Flysky rx. The problem was the Mamba Esc was too big to fit the in the spot... I'll just show you. I'm all done and it's fast as hell. It's raining outside or I'd take it under a street lamp. It's not waterproof anymore, but my thought was It rains only a few times a year here. It's raining now though

anyway... 



I found a longer bolt, but not too long. The bolt on the left was the one that came with the motor. The don't match, but it's like unmatched socks with long pants....



This is what I was talking about. I gutted the case for the 2n1 and then cut it because it wouldn't fit with the motor leads in that position. So I'm not using the 2n1 electronics for the case, just for the servo mount. Saved a little time and money.


Heres another shot. I almost cut it too close. But as you can see, the mamba isn't going to fit in there.


I installed an old Hyperion DS11 GCB (heli tail servo).






All done and wired up




That's a 30c 1300


Installed the switch here









I've got the aluminum drive and gear on order. I have aluminum shocks to install as well. I'm going to leave everything else plastic because once aluminum bends, it's garbage and plastics cheap. I'll take a little video if it stops raining tomorrow.

[r/c basher]

That's sweet! I see what you mean about the 2in1. I had the same problems installing the mamba in my rc18t too and did something similar to what you did. You'll be surprised at how quick it is outside.

[Doozer]

Thanks dude, you made me do it I went out and checked the road and it was halfway dry, and pretty dry under the street lamp. So I ran it for about 10 minutes. I opened up all the way one time on a line and it whizzed past me into the dark. So I was a little more careful. It has a ton more torque and jumps very smooth. The turning radius is much smaller now too. The speed difference is incredible.  I only pulled 550 milliamps off that 1300 pack. The ESC was barely warm and I could touch the motor without pulling away. Its kind of cool outside though. I was running a 12t pinion and the spur is 45t. The ESC manual says to run the smallest pinion available on 3S. So I'm going to switch back to the 10t pinion.  I'm pretty happy overall. Glad I went brushless. 

[Doozer]

Heres a video:

[Doozer]

What I have learned:
1) Getting the mesh right between motor and spur is critical. The slight rock method works, but I found a hand roll to be a better method (for me). I can feel how my pinion and spur are going to interact much better. I rolled both ways because if the mesh is too tight, your wheels will not turn. The 0808 5300 KV motor is not a direct fit, so you are left with a few choices. A) modify the motor mount, or B) Run with one bolt.  Because mesh is so important, you need to use the adjustable mount slot on the motor. That is impossible without modification or when you use two screws. 

2) The chassis brace holds the front bell cranks in place. The bell crank pins will dislodge from their mount on a heavy hit. I'm using the stock plastic brace. While all the molded plastic pieces are quite strong, they are still plastic, and the mounting holes for the bell crank pins deform. With the stock plastic shocks, keeping the pins in place becomes a chore. You might be able to keep the plastic shocks if you change the weight of your springs (make them stiffer), and/or increase the viscosity of your shock oil. I don't know if that will work. Before I even had this problem or ordered the aluminum shocks. When I realized what was causing the bell crank pin issue, curb jumps or flips, I decided to install the aluminum shocks. After installing the new shocks I ran through two packs with no bell crank issues.

You also might be able to buy the aluminum chassis brace, but then only one side of the bell crank mount becomes metal, though the bottom pin mount is longer and better reinforced. Replacing the shocks was 20 dollars shipped. The aluminum brace is $25 - $30 dollars depending on where you shop, and I'm not sure that will fix the problem. 

3) Customization... my first observation in this list is part of this observation. The Dromida is fairly proprietary. Making a universal motor mount, or several motor mounts for different aftermarket motors would be cool, but as of right now, they only make one, and that's for the motors they sell. Your wheel selection is limited because they don't use 12mm hex. You can buy adapters, but out of the box, I'm stuck with great wheels, but they aren't visually appealing to me. What if I feel like drifting the Dromida? Unless I buy their adapter, I'm SOL. However this isn't my biggest issue. 

When I bought the Castle Micro Mamba Combo, I wasn't thinking about gear ratios, but as you increase your voltage and discharge rates, your gearing should change. I wasn't thinking about this until after I installed the Mamba ESC because that's when I read the "manual."    According to the Mamba manual, the gearing ratio for 3S is "smallest pinion available," and "Largest spur available." Dromida comes stock with a 10t pinion, and they have multiple sizes. Though you could probably get a pinion the size you want anywhere. However, they only make one spur size, and that's 45t. Other manufactures offer multiple spur options. The TA RC18 offers a 60t in kit, and a 66t. It would be nice to have multiple spur options for the Dromida.

4) This buggy is extra "tuff," despite my whining above. I have beat this thing up over the last couple of days and I haven't had to replace any broken parts. The spur has held up to some serious pressure, and while it shows a little wear and tear, it continues to function as intended. By serious pressure, I mean quite a few runs with improper meshing. You can hear it in the video. When I played the video back while editing, my birds, that sit next to my computer, went crazy.  I haven't changed my mind about this buggy, but once you increase the power, it's hard to look back and say out of the box was fun. It was, or I wouldn't be here talking cars, I'd be finishing my airplane.