Matthew_Armeni

iTrader: (31)

+1 on this, the best motor is the one that works best for you. I'm currently running the Thunder Power 4.5 550 2 pole motor and love it. It's super smooth across the whole power band and has plenty of low end and more than enough top. The other Matt at Tekno is running the Tekin Pro2 5100 kv motor for similar reasons. Danny is running the Pro4HD 4300. All of our trucks work well

RCRijder

Thanks anr211, for the tip to look at the buggies for 4S battery weight, stupid that I didn't think of that before. (Given that I went for a 4S setup to easily add an EB48 buggy in the future). I see that Tekno advises a 600g battery to complete the EB48, and a 500g battery for the EB48.2, both with a Tekin Rx8 and 1/8 scale motor. My ESC (@110g) is heavier than an Rx8, but my motor (@265g) is lighter than a 1/8 scale motor.
The SCT410.3 is more like the EB48SL however, which is laid out for 2S and no 1/8 scale motor.
I read through the EB48SL thread and there are quite a few that do run 4S in their EB48SL. Most seem to go for the lightest pack that will still let them finish the race. I saw an SMC 5000mAh @539g, an unknown 3500mAh @410g, a Promatch @6500 605g, an Admiral 3600 @380g, an unknown 2200mAh @240g and the one that seems favorite: the SMC 3600 @334g. So basically everything from 240g to 605g is being used, with 334g packs getting good reviews.

Thanks also for the tip on quick and dirty weighing. When you remove the center screw in the shock towers, you can hang the car on a string, also giving a quick indication. Other options might be screwing a long screw in the lower front bumper center hole or a string around the rear diff coupler. Lower makes it more sensitive to dummy battery mass changes. I used the the big high center hole in the front bumper and a string through the rear shock tower buggy-body-mount hole, and measure the distance between the chassis and the floor. It is still quite inaccurate (mass changes of 50g do not create clear changes), but in this method it seems to need a 550g dummy battery weight to balance it this way.

Before I posted my question, I actually bought a set of 4 digital kitchen scales, but those appeared to contain random number generators instead of a measuring device, so I returned them.
What I did then to (try and) get a consistent reading on the scale was to tape a thumbtack on the bottom of the chassis, in the center between the wheels, tip pointing down. One in the rear and one in the front. For weighing a front wheel I would then balance the rear on the thumbtack tip, with one front wheel on a digital kitchen scale, and the other on a spacer block of the same height. This way the car would be level, and the effect of the hysteresis of the 4-wheel suspension is reduced. On 4 wheels, a difference in extension of the shocks influences the scale's reading, which would go unnoticed as I was only using a single scale. With one end of the car on a thumbtack underneath the chassis, a difference in extension between the remaining two wheels hardly shows in the scale. I removed the tires and rested the car on the flanges of the rims, so sideways friction was very low and did not influence the scale reading as much. It all seemed a good setup, but I kept getting different readings, and the four weight readings never quite added up to the total mass, or the added dummy battery weight…

I think I will go for an Orion battery and noticed that their biggest pack of 5000mAh does not even fit the battery tray without cutting it up. The biggest that will fit without problems is the Orion 4400mAh @500g. So unless anyone else has a brilliant idea, I will just get that one and see how it jumps. Probably the effect is not noticeable relative to other effects like shape of the ramp, angle of approach, throttle and steering angle, etc.

Thanks for all the invaluable information on this forum!
Cheers, RCRijder

RCRijder

Thanks HSV427. When running the SCT410.3 on 4S, most people seem to fear the increased wear in the constant velocity joints as the major concern. Actually the plastic spur gears and all diff gears seem identical in the SCT410.3 and the EB48.2 (which of course was built for 4S). The outdrives, cross pins, diff couplers, etc are all different. I will keep an eye on them, some of them are easily upgradeable once they wear out. I already bought all electronics except the batteries, so there is no way back now
Cheers, RCRijder

Hoese37

iTrader: (5)

You should be fine really. A lot of parts are included in the new EB48.3 kit.

Barillms

I have no idea why anyone would want to run their truck on 4s. It's simply 100% unnecessary.

PetRock

Higher voltage setups run with lower amp draws: running cooler and longer doing the same work. A SCT410 with a 2000kv 550 motor and 3600 4S is going to be the same weight and speed as a 4000kv 550 with a 7200 2S... but it's going to run at a lower temperature, a bit longer... and can use cheaper (lower C) batteries.

The biggest reason not to run 4S, is because the racing world only made a tiny jump from 7.2v NiMH to 7.4v lipos. If ROAR allowed 4S in 1/10th SCT (or any other 1/10th class) you'd see a huge number of people convert overnight. The batteries, ESCs and motors are all already available: but the 1/10th SCT class is pinned to arguably inferior 2S systems because of rule 8.10.13.2.1 in an old PDF.

(On a semi-related note: I'm happy to see more and more bashers support 4S-6S out-of-the-box - we need a large number of bashers to be running 4S+ systems to drag the racing world kicking and screaming into the future )

Millsy97

Hello, I've just ordered my SCT410.3 from AMain as they have 50 dollars off then another 10% which is a massive saving compared to the UK shops. With the truck, hobbywing sct esc and 4 sets of wheels it was around £50 less than the UK price!

Before I start building it I was wondering whats the best way to build the shocks, I'll only be driving the car on AstroTurf as that's what most tracks are in the UK.

Are there any out the box upgrade that are a must?

I've seen some people run the mechanical break and clutch, what are the benefits of this and how the hell would I set that up?

I'm looking forward to getting this truck built and getting it on the track

Dragonfueled

I'm running 4s because I bash and play around at the local park with my son. I don't know how you guys are getting decent speed and power on 2s without overheating the motor. I just tried a hobbywing 3400 on 3s and is was 254 degrees after a pack. Geared for about 45 just running it in front of my house. 4s 2400 castle motor finishes up around 150-160,
2s has to be really stressful on electronics. Even my slash 4x4's don't like 2s unless you gear them for about 30.

bds81175

iTrader: (20)

For racing, you only need to run for about 10 minutes max. If you gear it correctly, you can easily make the 10 minutes and finish with temps in the 150-160 range. It's part of the challenge of racing. That being said, I completely agree with PetRock above. This class seems to have gone in two directions from the beginning with the small, lightweight SC10 4x4 and the heavier, converted 1/8 buggies. If we had all opted for SC10 4x4 type vehicles the 2S batteries probably would have been fine. 550 2 pole motors would have been more than enough too. But we didn't...we chose the heavier path and the batteries just don't seem to be enough. I'm tempted to try 3S in my son's truck with his HW 4000kV at the club level.

qstorm777

iTrader: (2)

Me personally, I would love to see a lot of the clubs go to 3S. It would be easier on the battery, motor and esc. That being said, I wonder how many people will be satisfied with running at 40 to 45 mph and not stressing the system. Right now, my 410.3 is geared to be faster than my buggy. Only way I can compete. Wonder why there is a consensus to run buggy on 1900-2100kv motors, but everyone tries to push the SCT to the max. My SCT is geared for 45 and thats plenty. If I could run it on 3S at 45, I would love it until that 50mph SCT whoops my tail...lol. Anyway, I think 45/46 mph is that sweet spot for SCT. I would love to be able to run it at 3S. Maybe the batteries would last for more than 1.5 years.

Hoese37

iTrader: (5)

One word, Efficiency. Using the proper motor for a 4s setup gives better runtimes, cooler temps, and the same overall power.

JAE

iTrader: (30)

Since we are on the subject. Anyone have any reccomd rations for motor/esc combos under $225? Can size under 41mm in diameter? Thx

PetRock

SkyRC Toro 4300KV ($63) and HobbyWing SCT Pro ($85). Spend the remaining $75 on tires and some practice day fees.

JAE

iTrader: (30)

Thx - meant for a 4s setup. Having challenges for can that can support 4s that will fot in my Tekno and basher (mostly). Has to be under 41mm to fit

PetRock

Look on the same motor link I sent, and order the 1850kv instead. Keep the same ESC: both are rated for 4S.