MBX5T Speed calculation

[RRHobbydepot]

I need some good guesses on the top speed on a Mugen MBX5T. Its a standard 46/13 gear ratio on 5000 mah 30c 6s. weight is 10 lbs. tires are 4" diameter. 2200kv Castle brushless.

[bdebde]

http://www.scriptasylum.com/rc_speed/top_speed.html

[RRHobbydepot]

Originally Posted by bdebde

http://www.scriptasylum.com/rc_speed/top_speed.html

Thanks for that!

[magman]

Originally Posted by RRHobbydepot

I need some good guesses on the top speed on a Mugen MBX5T. Its a standard 46/13 gear ratio on 5000 mah 30c 6s. weight is 10 lbs. tires are 4" diameter. 2200kv Castle brushless.

First off...how fast are you looking to go? On 6s the 2200 will be screaming for sure. On 5s I run the 1600kv CC1520 and it does 45+ and is quick and has gobs of torque.

[magman]

I just ran #'s through the calc...w/your setup using a 13t pinion you are looking at 32mph, w/a 18t pinion you are looking at 44mph. The only issue is the motor RPM which is spinning over 43K which is too much IMO if you want the motor to last.

On a 6s setup a 1300-1500kv motor is best for longevity and good performance. If pure speed runs are what you are after, well then that's a whole different setup.

Just my 2cents worth

[RRHobbydepot]

Originally Posted by magman

I just ran #'s through the calc...w/your setup using a 13t pinion you are looking at 32mph, w/a 18t pinion you are looking at 44mph. The only issue is the motor RPM which is spinning over 43K which is too much IMO if you want the motor to last.

On a 6s setup a 1300-1500kv motor is best for longevity and good performance. If pure speed runs are what you are after, well then that's a whole different setup.

Just my 2cents worth

I checked the calculations also. The calculations all seem really low compared to what I thought some of the vehicles at the shop were running. I'm going to GPS some of the cars/trucks to check some of these speed claims. Especially the Traxxas toys.

[magman]

Originally Posted by RRHobbydepot

I checked the calculations also. The calculations all seem really low compared to what I thought some of the vehicles at the shop were running. I'm going to GPS some of the cars/trucks to check some of these speed claims. Especially the Traxxas toys.

For my setups I have used the calc and the speeds are spot on as to what I expected.

You said you were using a 4" tire....seems awful small for a truggy considering my badlands are 5"+

[bdebde]

Castle, HPI and Traxxas all say the 2200 is fine on 6s, although higher rpm than I like for off road, I think it is fine on road with proper set up. I ran a 2200 on 6s in an Ofna GTP geared for about 55mph, it was a blast... smoking burn outs that left black marks on the road.

[RRHobbydepot]

Originally Posted by bdebde

Castle, HPI and Traxxas all say the 2200 is fine on 6s, although higher rpm than I like for off road, I think it is fine on road with proper set up. I ran a 2200 on 6s in an Ofna GTP geared for about 55mph, it was a blast... smoking burn outs that left black marks on the road.

What was your gearing and temps on the Ofna?

[RRHobbydepot]

Originally Posted by magman

For my setups I have used the calc and the speeds are spot on as to what I expected.

You said you were using a 4" tire....seems awful small for a truggy considering my badlands are 5"+

I was in a hurry, 5 inch tires on the truggy.

[bdebde]

Originally Posted by RRHobbydepot

What was your gearing and temps on the Ofna?

I don't remember the gear sizes.... just geared for about 55mph. Temps were pretty warm 150 - 160, but still ok for the castle motors.

[magman]

Originally Posted by RRHobbydepot

I was in a hurry, 5 inch tires on the truggy.

Ok that's more like it....using that new info your speed should be somewhere around...

so...w/a 13T = 42
18T = 58

Again, the motor would be spinning at 43K