Brushless for XXX-T, need some advice

[scottcrisp]

Hi all, this is my first post to the forums, I didn't even know that Losi had forums. :-)

I'm a nitro buggy guy who is really having fun with my stock Slash, barely any parts breaking and it ALWAYS runs consitently. :D Don't get me wrong, I love the noise of my OFNA buggy, it is just more fun to not have to deal with tuning and expensive parts breaking from every little crash.

I was at a local carpet off road track last night running my Slash and picked up a used XXX-T for a really good price.

I'd like to put a brushless esc and motor in the truck. I looked at this Novak system

http://www.teamnovak.com/products/brushless/gtb_system/index.html (The 6.5R is what I'm, looking at)

I've never had a brushless system in a truck before and need to know what to expect, performance wise from the 6.5R system?

I'm a bit confused on the # of the motors, so if someone could explain that too, that would be great. :-)

I see videos of brushless trucks doing incredible speeds and a lot flipping over. I need a competitive system, not something that can't be controlled on the track.

The transmission in my truck is all stock, are there more rugged gears that I can install and not strip or is that not a problem?

I'll be running both on the carpet and on an indoor dirt track this winter. Not sure exactly how big the dirt track is going to be yet, the owner is still getting the building paperwork done and then they will start on the track. The last place that he had was pretty big, with the longest straight being about 100' and lots of technical jumps.

I'm not looking to break the bank on my esc/motor combo, so if anyone has any other suggestions for a good system, feel free to let me know that too.

Thanks a lot,
Scott

[TFrahm]

I can't imagine needing a 6.5 motor for an indoor carpet offroad track... Our local indoor (dirt) offroad track is BIG (450' racing line), and I race in the Expert Truck class with a 13.5 and it is plenty of motor. When guys try going to hotter motors (like the 6.5's), they almost always end up trying to "turn down" the end points on their radio to slow them down so they can drive them...

If you really feel you need more power than a 13.5 would give you, I doubt you would want more than a 10.5...

The smaller the number of winds, the "hotter"/"faster" AND harder to drive the motor is. 17.5 is considered "stock" now, and 13.5 is the "super stock" size motors -- 10.5 and lower is considered "MOD".

[Casper]

I agree with tom on this. 13.5 is a great motor to start out with. It is what we use in the super stock classes and is a lot of motor. The 10.5 is a great mild modified motor as well and will be noticably faster but still controllable. 6.5 is too much for a truck in most circumstances IMO unless you are a seasoned pro. Even then you will be able to controll it but probably go faster with a 7.5 or 8.5 for an indoor track.

The novak systems are good and there balistic motor series are great but look into the Xcelorin line of ESC's and motors. You can get a motor speedo combo for pretty cheap (around $225 new) and they work great.

http://www.losi.com/Search/Default.aspx?SearchTerm=Sensored_Combos

If you are stuck on novak stuff I would wait until the kenetic comes out.

[scottcrisp]

Thanks for the replies.

I had the numbers backwards, I thought that the higher the turn number, the faster the motors ran. Glad that I asked.

My brother-in-law has an Xcelorin Sensored system and it seems to run really nicely and has a great runtime. I'm not sure exactly what turn motor he has. I think he got his for around $175 at one of our local hobby shops.

I'm gonna look into one of those systems too. If I like it, I may end up putting one in a new OFNA SC-10 that I'm looking at. I like to have as much commonality as I can between what I have.

[Casper]

The sensorless systems are less expensive then the sensored so look at what you are getting. If you plan on racing then I highly recommend a sensored system. It will have smoother bottom end and more controllable. It is also requried if you are going to race stock at all since sensorless systems are not legal for stock.

$225 is the MAP so I bet you can find it cheaper then that if you look around.

[Audiobahnaholic]

I just ran second in the mod truck class at my local track with a XXX-T with a Novak 13.5. It doesn't take much motor just gearing and driver. A 10.5 should be plenty to win with every week. Sensored systems are sort of better but my mamba max runs just about as smooth as the Novak GTB.

[Casper]

I ran all but 2 of the JBRL races with a 13.5 in modified. I finished 2nd overall. Most tracks I went to more motor was not helpful. The guy who won the series also ran 13.5 for the entire series. 13.5 is not a bad mild mod and if you are new to 2wd electric it will be a great motor to give you good speed but control.

[Cooperd82]

one thing to keep in mind. is what kind of packs your going to run. goin from a Nimh to a lipo you can notice a difference.

[JESTER]

I ran all but 2 of the JBRL races with a 13.5 in modified. I finished 2nd overall. Most tracks I went to more motor was not helpful. The guy who won the series also ran 13.5 for the entire series. 13.5 is not a bad mild mod and if you are new to 2wd electric it will be a great motor to give you good speed but control.


I am a racer from TRCR in WA... 13.5 is our stock class. if i were to go mod i would have to go with the 8.5... thats what almost all our mod guys run or the 10.5.


anyone else run at TRCR????

[Revlimit]

I have to agree with the smaller motor is generally faster than a bigger motor. I run dirt oval and I was constantly getting beat buy season guys that were running 5.5s and 6.5s. I was running a 8.5, and was having problems laying down power, I got fed up with burning up tires every 2 weeks. So I picked up a 10.5 from the same manufature (speed passion) and I was running a whole lot better and my tires barely got any wear on the tires. And ended up finishing 2nd in my a feature, and beat out a couple seasoned guys with the "big blocks". The 10.5 was just butter smooth, compared to my 8.5, and a lot more controllable.

[greg]

I Just picked up a xxx-spec and want to go brushless. i am looking at castle sidewinder but they have kv ratings instead of t. i want to run in the stock class. they have either a 4700 or a 5600kv does either of them compare to a 13.5t? Also for battery choice i found turnigy 5000mah 7.4v 30c burst/20c constant for $45. are these godd batteries/price? and finally what is a good charger/balancer that does not require a power source or is it cheaper to get a power source and charger?

[Casper]

The castle systems you are looking at are sensorless. In order to run in the stock classes you HAVE to run a sensored motor so there is really no equivalent castle KV motor you can choose.

[Cooperd82]

I just put a Tekin RS with Losi KV4800. TON of power with 18/82 on 1st run. still fishing for good combo on the truck. Did 2nd run 15/88. ran smoother but setup is key when doing modified configuration.

hey Jester i run at TRCR i dont keep up alot on the truck forums. just started workin with it again.
*sorry for Hi-Jack*

[greg]

well i bought a castle sidewinder 5700 and am still shopping for the best price on lipo batteries/chargers. also i need a spektrum receiver so i can use my dx3s.

[scottcrisp]

Thanks for all of the replies and great advice.

I ended up with a Mamba Max Pro ESC and a Novak Ballistic 10.5T motor. I'm going to stick with 2c lipo packs until I learn some more about this brushless system and get some practice driving it.

I just need to get the gearing in the ballpark to start out with. The motor recommends trying to keep the final gear ratio to be around 9.5:1. I made a chart earlier tonight using 2.43 for the transmission ratio, that shows the spur/pinion combinations that get me right around 9.5:1.

I do have a couple of questions about this though.

1. I am currently using an 86T spur gear and using a 22T pinion will get me to to the 9.5 ratio. I also have an 82T spur and if I use a 21T pinion, it will also get me to 9.5 (actually, 9.49 or so). Is there any advantage to using one combination over the other, or does it not matter?

2. If all things were within the safe temperature zone for the motor and esc, which would ratio comes out to a higher tire RPM, a 9:1 ratio or a 10:1? (just trying to understand how the different ratios affect speed).