Battery Life

[ElectroTech]

Trying to decide on a new battery for my new wraith. Currently I'm running a little 1300mAh 3S 40C lipo, but I'm only running a Tekin HD 35T motor and I'm getting about 15-20 minutes of crawling out of it. I might stick with this for our local weekend comps since they are 3 5 minute runs. But I'm worried it will run out on me in a run and I don't want that to happen. Other thing is around Christmas this year I will be upgrading to a brushless motor and don't really know if they draw more or less juice. So I'm thinking of picking up a couple 2200-2500mAh batts which hopefully should last a good 30mins of constant run time.

[Rook82]

Brushless when comparing similar powered motors are much more efficient (in most cases). So if you change to a brushless motor and speedo of the same power level, you will get more run time from the brushless. You will not lose runtime unless you go to a more powerfull motor or change gearing, etc. There are cross reference guides around here so you know what to go for as far as a rating on a brushless motor depending on what you want. They are rated a bit different then a brushed motor. For example a 27 turn brushed motor is similar in output to a 21.5 brushless motor. May not be exact but it is close enough that many racing leagues let you chose between the two but be in the same race class. There is some debate on these ratings and equivalency, but the 21.5-27turn is a fairly common agreement. I know on some of my rc's I have gone to brushless. And even with now having more power, there was 25-30 percent more run time too. Very worth it. But the bad is brushless is no where close to working as well for slow speed crawling. I as well as many others have gone down that path. It is well doccumented on here. but if you want a basher or do a lot of high speed you will be fine. You will be spending a lot of money on a brushless system you can crawl with and it will still never have the low speed finesse the brushed has with current technology. Good luck whatever you do.

[tedo]

Originally Posted by ElectroTech

Trying to decide on a new battery for my new wraith. Currently I'm running a little 1300mAh 3S 40C lipo, but I'm only running a Tekin HD 35T motor and I'm getting about 15-20 minutes of crawling out of it. I might stick with this for our local weekend comps since they are 3 5 minute runs. But I'm worried it will run out on me in a run and I don't want that to happen. Other thing is around Christmas this year I will be upgrading to a brushless motor and don't really know if they draw more or less juice. So I'm thinking of picking up a couple 2200-2500mAh batts which hopefully should last a good 30mins of constant run time.

That seems like a really short amount of run time... In my old 3s 1300s, I could get around 40 minutes crawling / trail.

Do you have any binding? Are some of your wheel bearings rusted? A lot of stress can drain a battery quicker than normal.

[dittohead]

Originally Posted by tedo

That seems like a really short amount of run time... In my old 3s 1300s, I could get around 40 minutes crawling / trail.

Do you have any binding? Are some of your wheel bearings rusted? A lot of stress can drain a battery quicker than normal.

I agree. My 1300 3s lipos last at least 1/2 hour and thats a mix of crawling and bashing/trail running. Closer to 40 min run times. My wraith is brushless but i dont think it makes much of a difference, especially while just crawling. How old are your batteries? Balance them at all? The same 1300 mah batteries in my scx10 last over an hour easily. I expected less run time in the wraith because its heavier and its pushing larger tires. Im not even using good batteries, just cheap gen ace ones that are $25 each at the LHS

[ElectroTech]

The battery I am using is a 3S 40C 1300mAh Sky Lipo from Hobby Partz. It's brand new basically Only been through maybe 4 charges. The wraith is brand new also only been through 2 of the 1300mAh packs. I balance charge every time, truck rolls fine with the motor disconnected, no binding. It may be a little longer than 15-20 just seems that way. I'll set a timer on my next pack and judge it that way. Hopefully this will work for competition day and I will pick up another larger battery for bashing. I have a 5000mAh 3s Sky Lipo I use for bashing in my Exo terra, but I don't think I can fit it under the hood of the wraith.