davidd wrote:Oh, man! I almost wish I had not watched this! You're making me want to get a second MB Scaler to modify for actual rock crawling.
I'm looking at one of your prior videos, in which you say you changed out the wheels and tires, added taller shocks, and changed the motor.
Is a motor swap required to run super-slow over the rocks like this? Is changing out a motor a challenging project?
Did you do any additional chassis work other than changing the shocks? I assume the shock swap is to provide more clearance for the larger wheelset.
This looks like so much fun. I've barely run my MB Scaler, having purchased it more for its looks than to actually drive it, but man, you make running this rig look like so much fun!
Let's start with the motor swap. In my opinion this is the single best upgrade you can do to this chassis. Get a Hobbywing Fusion SE 1800kv brushless motor. They are around $80.00 U.S. and the ESC is built into the motor. So nothing else is required to do the swap. Dimensionally the Fusion SE is identical to the stock brushed motor. These motors are not fast but there slow speed capabilities and FOC technology make them perfect for crawling. You can also program the motor ( if you buy the program card ) and adjust things like the drag break, BEC out put, and a few other parameters as well.
To install it you must remove the body. That is done by removing the two screws at the front of the body. (The screws the body pivots on. ) Once the body is out of the way, there are two screws holding the transmission in place. You will see them at the rear of the transmission. Remove those two screws and the transmission lifts out. There are 4 M3 screws holding the rear cover on the transmission. Remove those so you can access the screws for the mid section of the transmission. You will then see 4 more M3 screws holding the mid section of the transmission to the motor mount plate. When removing the mid section be mindful of the drive pin in the upper gear set. The forward gear will want to stay put with the motor pinion allowing the drive pin to fall out. So be careful you don't lose that pin. With the mid section out of the way you can remove the motor from the motor mount plate. Install the pinion off the stock motor onto the Fusion, make sure you measure pinion height from the motor mounting surface on the stock motor before removing the pinion. The pinion will need to be at that same height on the Fusion for it to line up with the upper transmission gear set. Reinstall everything back together in reverse order and the motor swap is done. About a 30 minute job start to finish.
Now the shocks. This set up is going to sound weird, but trust me. The shocks I got are Yeah Racing Desert Lizard shocks. If you're not familiar with them, the springs are internal, and there are two springs in each shock. A short spring and a long spring. The shocks are sold in pairs and come with multiple sets of springs ( both shorts and longs ) so you can tune the shocks to the truck. The shocks are designed to have one spring under the piston and one above the piston. Off the top of my head I think I went with a 110mm long shock set up on mine. I didn't want to lift the truck a lot. But I wanted it to still flex. So I went with a longer shock than stock and set them up to ride at full droop. In other words, I installed the long springs under the pistons in the shocks and ran the short springs on the top. This allows the shock to have about 1/4 inch of downward compression, but allows the shocks to extend under flex. This keeps the center of gravity low and makes the truck much more stable over the rocks. It's actually not lifted much above stock ride height with this set up.
The tires and wheels were the easy part. I knew I wanted to run 2.2 inch rims, because scale wise that would be around a 15" rim. The tires are massive looking, standing at 5 3/4" diameter, but that plays out to roughly a scale 35" tall tire. All of which are possible to run on a early Willys MB or CJ Jeep with a mild lift. I will not lie, the tires do rub at times on the front inner fenders. I plan on trimming them in the future. Oh, and another mod you may want to consider is a servo upgrade. These big tires on mine didn't take long to nearly kill the stock 15kg servo that came in the MB. I upgraded to a 35kg digital servo off Amazon.
This Jeep is one of favorites to run. It is definitely fun to film while running it. I think I covered everything you asked about. If there is anything else you want or need to know feel free to ask.