badaml

iTrader: (132)

I have deleted my own post as it was probably unneeded

FROM THIS POINT ON PLEASE STAY ON TOPIC

egobrkr

iTrader: (29)

My thought was to run the motor for about an hour to get the gearing and heat that works. Do you thing that would be long enough to figure those two things out?

ifuonlyknew

iTrader: (7)

Proper gearing can usually be felt almost immediately. If it off, it is off. If it is under geared it will be slow, and get way too hot. If it is over geared it will be fast and way too hot. Put the truck on the track, run it for 5 minutes, check the temp. Run for 5 more minutes and check the temps again. It should be close to the same temp both times. Check one more time. What you want to do is gear it so the motor gets up to about 130°, and stays there no matter how long you run the truck. An hour should be plenty of time to figure it out.

egobrkr

iTrader: (29)

Thanks for the info. I will be using an orion R8 pro and a losi 13.5 motor. The R8 pro is a little overkill but that is what is laying around not being used.

egobrkr

iTrader: (29)

I got to run the truck yesterday and run times were about 40mins and temps were around 70f-80f. I got a novak 10.5t to try. Most of the guys are using the motor they already have and just turn down the endpoint on the throttle. I will run the 10.5 friday night ang see what run times and temps are.

ifuonlyknew

iTrader: (7)

Turning down your end points (epa) is the last thing you would want to do. End point adjustments only exist to set the travel on a servo. Using them as a band aid fix to slow down the car is not a good idea. Not only do you lose throttle feel, you greatly increase the likelyhood of esc failure. When the esc is anything but full throttle, there is this thing called ripple current, that is bombarding the esc. When yo go full throttle, the ripple current goes away. I know this may sound crazy, but full throttle is almost like a rest period for the esc. Taking that away by programing your esc with your epa at 100, and then lowering the epa will cause the build up of ripple current which will lead to the failure of the esc. When a team has an esc let go at this race, ask them if they lowered their epa. I almost guarantee their epa will have been turned down. Set your car up with the amount of power you can handle, then use the exponential in the radio, and all of the other adjustments in the esc programing. I will put it to you like this. I have a 7.5 in my 2wd buggy. I can run a 4000mah battery from full, down to low voltage cutoff, and my esc/motor are only warm. I can use full throttle on the strait, and a couple other parts of the track. My car is fast, and the power is very linear. If I had the batteries, I could easily run the car for 11 hours non stop. The 10.5 might even be better as you can get more power (as long as you as a driver can handle more power), and you can set it up with conservative gear as not to build heat. I bet a 13.5 coming off at those temps was not really that fast huh?

egobrkr

iTrader: (29)

I am a pro4 guy and this is my first dealings with 2wd. The 13.5 was slow to me but it was super easy to control. To me I think the 10.5 would be good on speed but not sure on run time. I assume the a motor with less turn would more efficient ( 10.5 more efficient then 13.5) as there are less whinds. I could be wrong just my thinking.

Dave H

In general higher turns are more efficient. The extra turns put more of the energy into the field creating the motor power. Less energy is lost to simple wire resistance.

Of course you need a balance of efficiency, and power for lap times and fun as discussed.

+ on not turning the epa down, not the best way to achieve the balance.

Also I believe moderate endbell timing (~15-20 deg??), and/or using a medium amount of esc boost could help, better balance of power and efficiency across the rpm range. Maybe even less endbell if using boost.