Savage XL outrunner conversion

[Semi Pro]

Differential Ratio: 3.3076923076923075 (Lst 2 Diffs)
Transmission Ratio: 1
Other Ratio: 1
Spur Tooth Count: 1
Pinion Tooth Count: 1
Total Voltage: 18.5
Motor KV: 380
Tire Diameter (inches): 5.75
Tire Ballooning (inches): 0
Motor Current Draw: 0
Motor Coil Resistance: 0
Spur/Pinion Ratio: 1 : 1
Total Ratio: 3.30769 : 1
Tire Circumference (inches): 18.06 inches (458.83 mm)
Rollout: 5.46:1
Total Motor Speed: 7030 RPM
Vehicle Speed: 36.36 mph (58.4 km/h)
Effective KV Value: 380
KT constant: 3.56 oz-in/A

[simplechamp]

Yeah I'd like to see that. Can't believe it would have enough torque at such a high rollout.

Here are a few pcis of the car and a short video:




Heres the video:

http://www.youtube.com/watch?v=MQDTGWeYi48

[simplechamp]

Seems pretty quick to me. Given your description before I thought it would be much slower. Still have some concern about that rollout though. Going to need a motor with more torque to have a cool running setup. Also maybe look at lower kv, higher voltage.

[Kcaz25]

Very nice!! Like you said though too slow and not enough torque. I love reading about outrunner projects!!

DanteX, how much does it weight?

[What's_nitro?]

If you bought a controller for 8s, I think this motor would work very well in your conversion. (If it fits) Turnigy Aerodrive XP 63-64 230kV The motor shaft is 10mm so you would probably need to turn it down, but otherwise it should have plenty of torque. Same RPM, same rollout, same speed- higher voltage, more torque, greater efficiency.

The whole thing with the time zones suck because while i am asleep you reply and i can read it next day. :(

@ Desmo: The car weighs 4,9kg (10.8lbs) RTR.

@What's_nitro?: I already bought a nice controller that can handle um to 12S Lipo and 100A! Yeah :)

But i dont want to spend so much money on a new motor. I probably will design a center diff drive for my savage or continue this build:http://www.rc-monster.com/forum/showthread.php?t=25375

Or i will buy this 5t body and strech the xl out :)
http://www.rc-fellas.com/product_inf...roducts_id=287

What do you think?

regards, DanteX

Originally Posted by DanteX

The whole thing with the time zones suck because while i am asleep you reply and i can read it next day. :(

@ Desmo: The car weighs 4,9kg (10.8lbs) RTR.

@What's_nitro?: I already bought a nice controller that can handle um to 12S Lipo and 100A! Yeah :)

But i dont want to spend so much money on a new motor. I probably will design a center diff drive for my savage or continue this build:http://www.rc-monster.com/forum/showthread.php?t=25375

Or i will buy this 5t body and strech the xl out :)
http://www.rc-fellas.com/product_inf...roducts_id=287

What do you think?

regards, DanteX

A much larger and lower kv motor should help. But I think as with my LST its to heavy. The best setup is some gear reduction. You can still use a outrunner but it just needs to be geared down. I think I'm going to put a center diff in my lst.

[MikeW]

Originally Posted by What's_nitro?

If you bought a controller for 8s, I think this motor would work very well in your conversion. (If it fits) Turnigy Aerodrive XP 63-64 230kV The motor shaft is 10mm so you would probably need to turn it down, but otherwise it should have plenty of torque. Same RPM, same rollout, same speed- higher voltage, more torque, greater efficiency.

How would you be able to mount the output shaft on the back of this motor?

I would be interested to do a savage 8s outrunner with this and the HC 8s-12s

The shaft goes threw the whole motor.
If this shaft is long enough you can loose the set screw and push it threw.

[MikeW]

Ok gotcha, thanks!

Finding a way to make the shaft smaller would be the only issue at this point.

[mrsnuggles]

i talked to steve neu and he said it would be no problem making a 1900 series inrunner with shaft extending through both ends in 8 mm

i'm planning a direct drive myself and my calculations are that about 200 kv motor is needed for 6s but lower kv for higher s count. these calculations are for bullet proof diff ratio and 7 inch tires.