"S" sized motor vs "L" sized motor - RC-Monster Forums

Metallover · **"S" sized motor vs "L" sized motor -** 11.16.2008, 09:28 PM

I am trying to choose a motor for my budget crt .5 conversion and I need to know the pros and cons of each size of motor. The motors I am looking at are similar to fiegaos in performance, probably a little greater. Here is a link to the motors - "L" "S"

The L motor is 300kv more then the S sized motor, and along with the size difference it will obviously be faster. The S sized motor is 50mm and the L is 60mm. I want to run 3s and about 4000mah and I want to hit 40-45mph.(although more is always better)

The questions I have is what kind of performance difference will there be between the two and what kind of runtime differences will I see. This is a budget project and I think I will need a $30 100a esc for the L which is rated for about 90a and I could use a $20 70a esc for the S which is rated for 60a. The 10 dollars I save could be used on a bigger lipo or go towards something else.

Right now I am leaning toward the L sized motor, but my opinion could change. I know all of you will say save up and get a medusa or Neu, but I just want something that works and is cost efficient. I can always upgrade in the future. I have owned a couple Neus for my vendetta and recoil and I know how insaine they are.

lincpimp · 11.16.2008, 10:16 PM

With similar kv the l can will make more torque due to the longer rotor. If the gear is optimized for the s can it will draw less amps, however if you are pushing the truck hard the s can may pull more. I would go with the l can as it will be more forgiving of gearing, and vehicle weight. Where will you find either esc listed with proportional brakes (car mode)?

E-Revonut · 11.16.2008, 10:24 PM

If you are serious about RC you might as well ditch a budget! Wants supercede needs in this hobby! Also as I have experienced in life whenever you buy a cheapo version of something better there's a reason why it's cheaper. Motor and esc are no place to skimp. Rather than trying to build this truck on your current budget wait a bit and save up the money to get a Medusa at lease, or put it on your credit card! A Mamba Max would be a good choice for an esc, again you may have to wait but the lifespan of a better esc is worth the wait instead of wasting $30 on an esc that will most likely die after a few runs. At the very least a Sidewinder esc.

Metallover · 11.16.2008, 10:35 PM

Here is a link to the esc - http://www.hobbycity.com/hobbycity/s...idProduct=7341 It is an airplane esc but I think it should work. The burst current is the only thing I would be worried about. I used the 40a version of this esc and it had a drag brake. The 100a has proportional brakes.

revonut you make a good point. This has been at the back of my head the whole time. I think I will wait and buy a used mamba max or something. I might wait for a cheap medusa or Neu too. I can always sell my nitro revo if I never drive it.

lincpimp · 11.16.2008, 10:38 PM

That esc would not be any use for a car. No real brake and startup will be poor. Buy a sidewinder or a MM.

E-Revonut · 11.16.2008, 10:47 PM

Sidewinder combos can be had for about $130 on ebay and MM combos a bit more, for new, or you can support Mike and order from him. I wish you luck on finding a used MM! I don't think anyone gets rid of them!

hoovhartid · 10:48 PM

I am running the 8L in my crt.5 (RCM converted)on 3s.

I ran two packs through it today. I have a 18t pinion gear on it and I am running the stock 3.5" wheels. I use a MM ESC. and a BEC. I think its geared for about 40. It was great on the track today. the motor never got above 130F Tho, I am using an RCM heatsink/clamp. and I was only able to go about 20 minutes or so with each pack....not because I ran out of power, but because I'm a crappy driver and I kept breaking stuff

all n all, i'm happy with my hobbycity "spinning toaster of death" as suicideneil likes to call them.

I recommend the L size as well, tho running 3s with a 3500kv puts you pretty close to the 40000rpm mark, and these tend to run hot. you may want to consider the lower kv motor.

....then again, if you get the higher kv motor, and it runs good......let me know!

Metallover · 11.16.2008, 10:50 PM

Quote:

Originally Posted by hoovhartid

I am running the 8L in my crt.5 (RCM converted)on 3s.

I ran two packs through it today. I have a 18t pinion gear on it and I am running the stock 3.5" wheels. I use a MM ESC. and a BEC. I think its geared for about 40. It was great on the track today. the motor never got above 130F Tho, I am using an RCM heatsink/clamp. and I was only able to go about 20 minutes or so with each pack....not because I ran out of power, but because I'm a crappy driver and I kept breaking stuff

all n all, i'm happy with my hobbycity "spinning toaster of death" as suicideneil likes to call them.

I recommend the L size as well, tho running 3s with a 3500kv puts you pretty close to the 40000rpm mark, and these tend to run hot. you may want to consider the lower kv motor.

....then again, if you get the higher kv motor, and it runs good......let me know!

What lipo are you running?(mah)

hoovhartid · 11.17.2008, 12:45 AM

its a zippy 3s 4300mah 20-30c

GO-RIDE.com · 11.17.2008, 05:49 PM

I agree with other posters. Save some $ over time and get a Mamba Max if you want to run 3S or at least a Sidewinder. As for S can vs. L can, if the 50mm Feigao is anywhere near as powerful as the 50mm Medusa I'm using you will have all the motor you will ever need unless all you do is speed runs. I'm using 1/2 throttle to clear 25' triples with a Medusa 50mm x 3300. At full throttle it would probably clear 40' and that's with a 15' run in.