Some rock force questions

[scho0643]

Hi everyone,
My fiancée bought me a rock force as an engagement present. It will be here next Wednesday and I'm trying to get some things sorted out before it gets here. I'm on a budget (weddings are expensive lol) I'm not looking to be "comp ready", I just want to have something to play around with, so this platform seems durable and fun...
1. I'm thinking about going with the Novak ballistic brushless system, any thoughts? I don't even know if I really want brushless, I just want it to work.Any suggestions on motor/ esc combo? High speed gears?
2. Do I want to go with lipo? I would need a new charger also but a 2s lipo seems like a good balance between cost and effectiveness. Thoughts?
3. How much shock oil do I need? They look like they come in 2oz bottles?

Thanks for any tips!!
Kyle

[warriorsimi]

i have seen one but never had one,the rock force has worm gears so if you go brushless you will probably mess them up right away,i would probably start with a brushed tekin system 2 cell lipo maybe get some beadlocks cause i think they are glue on rims just make sure the rims will fit the axles.you will also need a set of decent tires,shock oil one bottle should be enough not sure on ounces though.hope this helps ,this is just what i think but don't quote me cause i never had one just looked at one i was going to buy.

[EeePee]

If you're up for maintaining a brushed motor very often, then you'll be okay, but if not, then go brushless. You might want to pass on the Novak ESC if you're thinking of using the Goat. They fail with no warning. Try Tekin instead.

Buy some spur gears as I found that to be the weak point.

I'd suggest the high speed gears because the thing is pretty dang slow with the stock gears.

Skip the dig for the rear axle, it doesn't work very well, though if you're not comping, you may not care and dig is pretty useful.

Lipo, of course. Best battery chemistry out there, by far.

The shocks are supplied with a piston that is very limiting if I recall correctly. I remember running 15 weight oil and the shocks were still very slow.

I have a build thread on mine, feel free to take a look, it should have some pretty useful shit in it.

[scho0643]

Thanks for the tips EP. I have read your build thread a couple times actually lol. I have looked at the tekin systems a little bit but it seems like they are really expensive ($300+)? Any more affordable systems thatight be worthwhile? I see most people go with 3s lipos here, is there a big difference in my situation between a 2s and 3s?

[EeePee]

Yeah, about 4.2 volts of a difference.

It's substantial, really.

If you're willing to possibly deal with a problem with the Novak, then there's no reason to not get it. Not saying it's going to fail, I'm just saying that it might. But really, so might anything else. Personally, I've had Novaks fail, Tekins fail, and a Castle Creations built Holmes Hobbies BR-XL failed, too. But there was a long period where many people were having their Novaks fail, like a bad batch or something.

Oh, and definitely get some new tires, the included stock tires are a joke. Try some Hot Bodies Rovers or Sedonas.

Yeah crawling is funny, it seems cheap, until you realize most kits need another bunch of money to get them going good.

[scho0643]

Yeah it's really adding up, but I'm excited to get a box of gears and screws and plastic in the mail, I haven't had the pleasure of building a kit in a while. Any recommendations on what specific batteries to get? I've never ran lipo's before..

[EeePee]

I'm a fan of Hyperion, if they aren't the best, they're very close. But many people use the cheaper Hobbyking Turnigy or Rhino or whatever they are lipos.

HobbyKing R/C Hobby Store :

[moes670]

Look at the Mamba max pro for an ESC you can run brushed, sensored and sensorless brushless with one esc. I have ran both the novak goat 2s and 3s versions in my rockforce and both have had thier issues. You will need an external BEC with the MMP the internal one is weak sauce.

[difflocker]

What pinion/spur combo would be a good starting point with the Novak Goat 3s ESC and Ballistic 21.5 brushless motor on 2s lipo?

[EeePee]

Skimming the first few pages of my old build thread I see I went from a 18 tooth to a 26 tooth and that netted me nearly 100:1 ratio. I ran a 3S lipo and a 10 turn Holmes Puller.

Then I kept reading and grabbed a couple quotes from me.

I did recently switch over to an Integy 35 turn motor and a 84 tooth spur with the stock 18 tooth pinion which put the final ratio at 70.00001 with the high speed gears in the axles. The ESC runs a bit hotter than I'm used to it running, but the motor temps are cool. And since the ESC has thermal protection, I don't care if it gets too hot.

I have the stock 86 tooth spur, and a 26 tooth pinion with the HS gears for a total reduction of 49.6 to 1. I was aiming for a nice and even number, like 50. My AX10 is at 47.8 to 1 so I tried to get the Kyosho close to that.

[vipxj]

I run an 86t spur/18t and a 35t on 3s,FXR ,HP gears. its got good torque,wheel speeds allright, and both dont get to hot . I think its a good combo.

[difflocker]

Thanks for the info guys!

[moes670]

16/78 with a ballistic 21.5t. It will take mods to get gears that small in there but it will give you an idea of the ratio. This was with the high speed gears and a MMP on 4 cell. Good low speed control and awesome wheelspeed. Even more so running about 30° of timing with the cheat mode.

[scho0643]

so i ended up ordering the ballistic brushless system. and lipos on the way. The truck came in the mail yesterday, i am sure i will start assembling before the elecronics get here!!

does anyone have a suggestion on what kind of grease to put on the worm gears?

[moes670]

I found this stuff to be the best out of everything I tried.

LOCTITE MOLY-50 Metal-Free Thread Lubricant Moly-Petrolatum 1 lb - Loctite - LUBRICANT

Make sure you are sitting down when you look at the price though. I was lucky enough to get a scoop or two out of a can brought into work for some bolt torque testing. Any of the other "greases" out there just don't compare.

Whatever you use don't be shy about getting a bunch in there. I ended up drilling the housing for a fill hole so I could shoot some in there now and then with a syringe.

[scho0643]

Holy Crap that's out of my price range, anything less expensive that would get the job done? Lol

[moes670]

Antiseize may be another one to try. I never have though. I have tried the losi grease and it has worked well.

Losi Hi-Pressure Black Grease (8cc) [LOSA99203] | Glue, Oil & Cleaners - A Main Hobbies

Sure you could find the same stuff cheaper in this tube. Amazon.com: Plews 11-335 14 Oz Moly EP Grease: Home Improvement

[EeePee]

Just use a wheel bearing grease, as in any high temp EP moly grease. EP just stands for Extra Protection. Advanced Auto, Auto Zone, whatever, they all have it.

[scho0643]

Awesome. Thanks for the tips guys

[ReaperGN]

I have had good luck with "Green Grease". You should be able to find it at any local auto parts store.