8ight-racer

iTrader: (5)

Hi everyone, I'm building a realistic semi-truck and trailer which will weigh about 30 lbs under max trailer capacity. The truck only needs to go 20mph top speed and accelerate as quickly as the real one, which won't be a problem.

That being said, I'm looking for recommendations for motors, ESC's, and batteries that will handle this load. At first I was looking at 1/8 sensored systems, but now I'm looking at a 1/5 system such as the Mamba XL and 2028 800kv motor. What cell lipo would suffice? Because I'm modifying much of this, there isn't any limitations for motor or battery size.

Any recommendations would be appreciated! I've raced 8th buggy for years but have never done much research on large scale vehicles.

Dave_S

iTrader: (1)

Budget?

8ight-racer

iTrader: (5)

I'm open to anything below ~$500 so budget isn't a big issue.

cdub_OffRoad

iTrader: (1)

What are you thinking transmission wise? Gearing will be critical. With the right gearing, I see no reason an 1/8th scale power system wouldn't work. I think you might be surprised how fast 20 mph feels with something this big and heavy. I'd shoot for half that as my run-out speed, and put in something like a Tekin RX8 and a 1400 kv truggy motor. Go ahead and run a 4 cell or even 6 cell lipo, the higher voltage is your friend from an efficiency and heat standpoint. Your total gear ratio is going to need to be around 40:1 or maybe even more.

the rc guy

40 lbs might be alittle to much for a 1/8 scale motor and esc .id run a 1/5 scale in the 800 kV range then gear accordingly.. 6 cell might go with 3 x 2 cells.. then when a pack gets tired replacement wont be a big drain.

cdub_OffRoad

iTrader: (1)

Maybe we are over thinking this. Take a look at the motors and gearboxes in ride on powerwheels toys. Those easily handle 100 pounds, and are cheap and brushed.

8ight-racer

iTrader: (5)

Thanks everyone. I'm going to use the Integy 3-speed semi truck gearbox, which has a FDR ratio around 10:1 to 30:1 (basing it off the Tamiya 3-speed). That being said, any other multi-speed transmission recommendations would be appreciated because I've never seen or used this Integy one before. We will mount a servo so we will have the ability to change gears while driving.

I am leaning towards the Tekin RX8 and a 1400-1550kv motor on 4S lipo because we only need to go up to 18-20mph. The load will be 20-30 lbs max and it won't be driven hard for long periods.

Also, the full tractor (semi truck without trailer) weight is 6 lbs at 1/14 scale, so that would rule out some of the heavier 1/5 scale motor/esc combos with 6S lipo.

DJ1978

iTrader: (3)

You can't go wrong with any of the Tekin or Castle systems for 1/8th scale. That really is not much weight, even with the trailer. Go with a sensored system.