RC-Monster Forums

RC-Monster Forums (https://www.rc-monster.com/forum/index.php)
-   Brushless (https://www.rc-monster.com/forum/forumdisplay.php?f=12)
-   -   Can a lehner 2250/10t (1183kv) pull this combo (https://www.rc-monster.com/forum/showthread.php?t=12253)

crazyjr 05.21.2008 03:50 AM

Can a lehner 2250/10t (1183kv) pull this combo
 
I was playing with BrianG's speed calculator Thanks Brian, its a great dream tool) and i am thinking of building a speed MT. I don't know if it will ever compete, but you never know, it may come to the east coast. Here is the setup i run on the calculator:

Differential Ratio: 3.3076923076923075
Transmission Ratio: 1
Other Ratio: 1
Spur Tooth Count: 44
Pinion Tooth Count: 25
Total Voltage: 29.6
Motor KV: 1183
Tire Diameter (inches): 5.6
Tire Ballooning (inches): 0
Motor Current Draw: 0
Motor coil Ω: 0
Spur/Pinion Ratio: 1.76 : 1
Total Ratio: 5.82154 : 1
Tire Circumference (inches): 17.59 inches (446.86 mm)
Total Motor Speed: 35016.8 RPM
Vehicle Speed: 100.21 mph (160.97 km/h)
Effective Speed Rate: 3.39 mph/V (5.44 kmh/V)
Estimated Adjusted Speed: 86 mph (138 km/h) - 14% loss
Effective KV Value: 1183
KT constant: 1.14 oz-in/A

I know the 2250 is a frighteningly powerful motor (center diffed Twin Force and still wheelies) What i want to know is, Can it pull the underlined ratio with approx. 5.6" MT tires? I didn't figure in ballooning in and replaced the current diff(ofna/51 spur) with a hot bodies/kyosho 44 tooth spur. in the figures. I figured this on 8s lipo's and 3.7v per cell

This is being theorized around a Kyosho Twinforce, with a center diff (one of the ones sold by Promod a while back) Anyonw with lehner 22 series experience prefered, but open to all opinions

BTW the current setup with an MGM 16018 pulled 2584watts peak with 6s lipo's geared for 49mph, current gearing is 19/51

jzemaxx 05.21.2008 11:01 AM

That motor should be able to pull it that fast. The calculator above 75 though starts becoming in-accurate. The drag factored in must not be enough......

BrianG 05.21.2008 12:15 PM

Quote:

Originally Posted by jzemaxx (Post 175213)
That motor should be able to pull it that fast. The calculator above 75 though starts becoming in-accurate. The drag factored in must not be enough......

The drag factor is a VERY rough estimate. In very streamlined setups, the factor may be too high; in not-so-aerodynamic setups, the drag may be too low. So, I opted for "about in the middle". A MT is much different than an on-road car. :smile:

If the mood grabs me, I might add a drop-down box so the user can select vehicle type. Similar style vehicles should exhibit somewhat similar drag characteristics.

lutach 05.21.2008 12:24 PM

Here are some datas of a few 2250, but not the 2250/10:

http://www.lehner-motoren.com/motord...250-11.33V.xls
http://www.lehner-motoren.com/motord...20HA%2049V.xls
http://www.lehner-motoren.com/motord...6%20HA.24V.xls
http://www.lehner-motoren.com/motord...6%20HA.28V.xls

This should give you ideas of how well the 2250 will do.

jzemaxx 05.21.2008 12:30 PM

Quote:

Originally Posted by BrianG (Post 175237)
The drag factor is a VERY rough estimate. In very streamlined setups, the factor may be too high; in not-so-aerodynamic setups, the drag may be too low. So, I opted for "about in the middle". A MT is much different than an on-road car. :smile:

If the mood grabs me, I might add a drop-down box so the user can select vehicle type. Similar style vehicles should exhibit somewhat similar drag characteristics.


That would be awesome...I can give you feed back as to how much you will need for the drag estimate given all the runs I have done with my setup.

crazyjr 05.21.2008 12:51 PM

Thanks, guys, I figured it could pull the ratio. The 2250 is a powerful motor, almost too strong (I'd hate to see the damage Aquwt has done with the 2280 he has). Lutach, Those graphs are confusing to me. on the W (I assume thats watts) Why are the lower winds only in the hundreds and like the 14t is 1800w?

lutach 05.21.2008 01:18 PM

Quote:

Originally Posted by crazyjr (Post 175254)
Thanks, guys, I figured it could pull the ratio. The 2250 is a powerful motor, almost too strong (I'd hate to see the damage Aquwt has done with the 2280 he has). Lutach, Those graphs are confusing to me. on the W (I assume thats watts) Why are the lower winds only in the hundreds and like the 14t is 1800w?

That's the reason I only gave you those links. They are more of what we'll see RPM wise. The 2250-11 for example, they tested it with 33V and the last line shows 31V, 150A, 4621 watts and 93.4% efficiency. Now that's good for me. If you want nuts you can actually do almost the same to your 2250-10 as Lehner did to the 2250-14HiAmp. Get a nice and strong 12S controller that will do 120A or so and let the monster fly. If you find a Schulze 40.160, you can even go as high as 300A and it will take some pinion and batteries to pull that one, but you can be sure the Lehner might take it.

crazyjr 05.21.2008 01:30 PM

Thanks Lutach, So the graph is for different voltages with the same motor? I know the motor would wake up with more voltage, but want to do this on a budget. My plan is for using a MGM 16024 i got laying around (got to send it in for a glitch and update programming. Honestly, the motor on 6s is awsome

lutach 05.21.2008 01:47 PM

Quote:

Originally Posted by crazyjr (Post 175267)
Thanks Lutach, So the graph is for different voltages with the same motor? I know the motor would wake up with more voltage, but want to do this on a budget. My plan is for using a MGM 16024 i got laying around (got to send it in for a glitch and update programming. Honestly, the motor on 6s is awsome

You should see them over 30 volts. With 8S you will see a completely different motor, even though you only went up 2 Lipo cells.


All times are GMT -4. The time now is 07:50 AM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2025, vBulletin Solutions Inc.