Page 2 of 3

Re: Lipo Question

Posted: Thu Feb 10, 2011 11:02 pm
by Charlie don't surf
mainesrc10 wrote:Sorry, a little new to this. What do u mean by 10.5(wheelies from a stop and 1/2 throttle) and 8.5?(backflips from a stop and wheelies from 3/4 throttle)

Re: Lipo Question

Posted: Sat Feb 12, 2011 10:23 am
by THEYTOOKMYTHUMB
mainesrc10 wrote:Sorry, a little new to this. What do u mean by 10.5 and 8.5?
It has to do with sensored motors vs. sensorless motors. Sensored are measured in numbers like those above. Similar to turns on a brushed motor. The lower the number the more rpm. Sensorless are measured in kv(i.e. 5200kv). The higher the number on these the higher the rpm. There are charts that will show how they translate to one another, but I don't have a link handy. A quick google would probably give you a chart and more clear explanation than mine. If you're running a 5200kv motor then it means you have a sensorless esc. Fine if not preferred for bashing. As far as lipo goes I wouldn't stress over it too much really. I see 20c packs outrun 60c packs and vice/versa. In the hands of a great racer the difference might be clear, but for average joes(like myself)it's not that big of an issue. I have 50c Maxamps packs that I paid $150 for, but run one of these below in A mains(when I get there! :lol: ). I have 2 of the ones below. They are identical technically, but one is stronger than the other. In fact, as I stated it's even stronger than my Maxamps packs and as strong as any pack on the track. The lesser one is still very solid. Sorry to go on so long...sometimes I just have to say to myself "OK stop typing now!". :lol: Then again the lipo part of my post is strictly my opinion, and you know what they say about opinions... :lol:


http://cgi.ebay.com/7-4v-5000mAh-30C-Lipo-2-Cell-2S-7-4-RC-Battery-AKKU-WF-/160544667539?pt=Radio_Control_Parts_Accessories&hash=item2561353793

This is a softcase so keep that in mind. Some tracks don't allow them and they are more prone to puncture. I think you would have to be doing something pretty careless to puncture one though. Just make sure it's strapped in well. The link BrandonG gave is a hardcase and might be a better choice for you.

Re: Lipo Question

Posted: Sun Feb 13, 2011 11:19 am
by tim.sanderson
THEYTOOKMYTHUMB wrote: There are charts that will show how they translate to one another, but I don't have a link handy. A quick google would probably give you a chart and more clear explanation than mine.
I found this on another forum, posted by someone who works for castle creations.
  • 4600 = more than a 12T
    5700 = more than a 9T
    6900 = more than a 6T
    7700 = more than a 4T
    9000 = more than a 2T

Re: Lipo Question

Posted: Sun Feb 13, 2011 1:31 pm
by mainesrc10
Yea, it says its a 9.5t. What would be some good gearing to start at. Lookin for top speed, for drags. Thanks

Re: Lipo Question

Posted: Sun Feb 13, 2011 1:50 pm
by THEYTOOKMYTHUMB
I'm terrible at the technical stuff so I can't say exactly(I tend to eyeball everything :oops: ), but I would say as low as possible. :wink:

Oh wait...once again I should read more carefully before posting... :lol:
If you want top speed gear as high as you can...if you're like me you'll go super fast and hit a mailbox. Then you'll just need to worry about what to buy next... :lol:

Re: Lipo Question

Posted: Sun Feb 13, 2011 7:27 pm
by mainesrc10
Just got new street tires, and they are a little smaller in diameter. Was just wondering if this will give me more top speed or lower end. Thanks

Re: Lipo Question

Posted: Sun Feb 13, 2011 7:30 pm
by nvxwax
mainesrc10 wrote:Just got new street tires, and they are a little smaller in diameter. Was just wondering if this will give me more top speed or lower end. Thanks
Low end

Re: Lipo Question

Posted: Sun Feb 13, 2011 7:31 pm
by Coelacanth
mainesrc10 wrote:Just got new street tires, and they are a little smaller in diameter. Was just wondering if this will give me more top speed or lower end. Thanks
All else being equal (i.e. same gearing), smaller-diameter tires will reduce your top end and improve low-end acceleration.

Re: Lipo Question

Posted: Sun Feb 13, 2011 7:32 pm
by mainesrc10
K thanks. Any advice on gearing numbers for top speed.

Re: Lipo Question

Posted: Sun Feb 13, 2011 7:34 pm
by tim.sanderson
Here's a site that can show you a good place to start:
http://www.comeseethis.com/gearing/Default.aspx
Basically, you need to select your car/motor/gearing etc, and it gives you a range of gearing that would be safe to use.

Re: Lipo Question

Posted: Sun Feb 13, 2011 7:36 pm
by mainesrc10
That would work great, but my motor is not listed in there. It was just a throw together so the motor is a hobbyking 5200kv and 100amp esc

Re: Lipo Question

Posted: Sun Feb 13, 2011 7:55 pm
by mainesrc10
I have 20/85 on there now and tops out at like 40-45. Shouldnt it go faster with a 5200kv on 2s? Thanks

Re: Lipo Question

Posted: Mon Feb 14, 2011 5:38 pm
by mainesrc10
Any advice?

Re: Lipo Question

Posted: Mon Feb 14, 2011 6:12 pm
by tim.sanderson
I think you're pretty much going to have to go the temperature route...
Run it for 2 minutes or so, the feel the motor. If you can't keep your finger on it for 3 seconds without getting burned, it's too hot/geared too high. If it's still cool to the touch, keep going up a gear or 2 until it gets warmer. Anything under 180°F , and you're ok

Re: Lipo Question

Posted: Mon Feb 14, 2011 11:31 pm
by mainesrc10
The esc and motor says it has an over heat protection on it, and will shut down if to hot. Can I just keep gearing up untill it shuts down then back it off a tooth or two?