Tekin rx-8 & 1350 kv mtr

[Zieg-Zag]

Does the Tekin rx-8 with the 1350 kv motor seem like a good setup for my summit. Id like a little more speed the torque for some crawling.

[humayrayakongkinaon]

you want more speed, get the ones with higher kv. lower kv put out higher torque but requires a good set of batteries.

[jamann]

1700 to 2000 kv seems to be the sweet spot for this truck.i ran/run 2000kv torque was never a issue,and it was more than enough faster


Sent using lipo power

[stickychinsac]

I believe the 1350 is pretty close to dewalt kv but would need 6s to be happy. Would be able to gear it through the roof i would imagine but like jamann said you would probably be more happy around 2000kv

[krallopian]

As said so many times on this forum, kv is about as easy as reading, "how many rpm per volt" so if you have a 14.4v (2x2s lipo) setup, that's 14.4 x 2000 = 28,800rpm. Mix that in with the pinion, spur and transmission and you can get going very fast. Now take the 1350 on the same 14.4v setup and you only get close to 20,000rpm and that simply isn't very fast, BUT you then put the 6s power in there, 22.2v and you're suddenly back up to 30,000rpm. So there's clearly more than motor speed that is important, it's how you are going to power the motor.

I've read multiple times though that parts start twisting up with too much torque on these cars, so although you can get the spur spinning very fast on 22.2v, you're probably going to end up twisting/cracking/snapping/ruining something with all that torque.

As suggested, 2000-2250kv is a very good idea.

[jamann]

As said so many times on this forum, kv is about as easy as reading, "how many rpm per volt" so if you have a 14.4v (2x2s lipo) setup, that's 14.4 x 2000 = 28,800rpm. Mix that in with the pinion, spur and transmission and you can get going very fast. Now take the 1350 on the same 14.4v setup and you only get close to 20,000rpm and that simply isn't very fast, BUT you then put the 6s power in there, 22.2v and you're suddenly back up to 30,000rpm. So there's clearly more than motor speed that is important, it's how you are going to power the motor.

I've read multiple times though that parts start twisting up with too much torque on these cars, so although you can get the spur spinning very fast on 22.2v, you're probably going to end up twisting/cracking/snapping/ruining something with all that torque.

As suggested, 2000-2250kv is a very good idea.

A fully charged 2s lipo is 8.4v so
16.8v x 2000kv = 33,600 rpm .....etc



Sent using lipo power

[stickychinsac]

1700 tekin on 4s is very comparable to the dewalt geared stock (1700 wants 6s and can grunt through tall gears though). Whichever motor you decide on I would advise you go with the truggy size rather than buggy. buggy motors are shorter and lack the torque, although still have more than enough power to bring a smile to anyones face.

[Zieg-Zag]

thanks for all the info. Ill definitenly be running the truggy mtrs. I figured with a lower kv mtr I could run a bigger pinion if I want more speed, and switch in a smaller one if I want to do a little more crawling. It would seem that the lower speed motor would be more conducive to crawling.

[jolynsbass]

Indeed, even though they are sensored motors, you'll have all the more fine control over the low-end speed if you choose a lower kv motor. You only need >1700kv if you want to do speed runs, and the Summit is just no made for that. If you want fast, get an E-revo.

It's funny, 'cause I told my friend when I got my Summit that I already have cars that go fast (two Rustlers), this car is meant to go slow. He thought that sounded boring - then I took him driving with me, crawling over some great rough terrain, and he thought it was more fun than anything else he's done with RC!

[stickychinsac]

2000kv is perfect on the truck, run 4s at full potential

[satyrisci]

well, I bought my brushless motor for $50(new) and my ESC was $40(new). But if you want to do a lot of rock crawling, you would want a sensored motor for more torque and less cogging. PM me if you want to know where to find a 2350KV sensored brushless motor for bashing and crawling for $60 before shipping. Untill about a couple weeks ago, a motor like this was over $100.

[stickychinsac]

get what you pay for??

[satyrisci]

get what you pay for??

If you care in what brand name is printed on your motor, yes. If you don't care what brand name is printed on your motor, then no.