ASK Cubby, 03.27.2014, Version- Your Questions, My Ridiculousness

“Halix build
I am very interested in your Vaterra Halix project. This has been one of my all time favorite trucks. I’ve upgraded the wheels, tires, and shocks. It is much better than stock.
You may ask why, but I wondered if you had any suggestions for upgrading the motor?
Any input is appreciated.
Thanks
Dave”

Cubby- Yo Dave, just like you we are big fans of the Vaterra Halix. It looks cool, drives awesome, and has good yank right out of the box. But… “good’ is never enough, therefore we started a hop-up series on the Halix. You’ve probably already seen the first couple of installments and we’ve got several in the can on the way.

Yes, later in our hop-up series you’ll see us throw in major power. We did so to have the ability to rip off massive backflips (on the ground and in the air), and to generally overpower it just like every good basher should.

What would I recommend for you? First, upgrade to MIP CVDs, they are a must on big power with the Halix. Then… the Halix comes stock with a 540 sized motor, it could really use a longer 550 for more torque to turn those big tires over. There is plenty of extra space for a longer can, and it will bolt right up. To get specifics on brand, gearing, cell count etc, you’ll have to wait a few weeks for our hop-up article. 🙂

Hit the “Read More” button for the second letter of the week, one that asks how to go high speed running with an 8th scale buggy on a $70 budget.

“Can you please help me
“Hi Cubby!
I just read your article on building a RC Dragster and also come across a lot of your comments on different forums. So hoping you can please help me.
OK, I have a 1/8 nitro buggy that I converted to brsushless, me and a large number of friends like to do a lot of parking lot drag racing. I am needing help finding a good cheap motor and gearing for getting this thing from point A to B the quickest. However, I have a really limited budget of about $70 at the moment which I know isn’t that much and makes this all the more complicated, as well as interesting and fun for me.
I have a 120a ESC, 3S Lipo (willing to buy a cheap 4-6s lipo if the motor is not too expensive), 48t spur, and 14t pinion at the moment. I think I can get a 46t spur and room for as big as a 20t pinion all the way down to 11t pinion (if i use a motor that has a 36mm diameter, NOTE I have a choice of 2 motor mounts).
So with 36mm motor diameter i can get down as low as 11t pinion and as big as 14t pinion, but with the other mount I can use 40-42mm diameter motor but only 14t pinion at the smallest and maybe 20t pinion at most. I don’t have the money these other guys have to go out and buy the best high end stuff, so i been looking at Tacon 3674mm motors and Hobbyking motors.

What KV am I needing, possible gearing, on 4s lipo to get this buggy from one end of a probably 60-70yd parking lot? Some places I read say to use smallest pinion and biggest spur, others say the exact opposite. I guess heat isn’t too much of an issue since im only going to be making 1 pass and then have time to cool down.

Sincerely,
Jimmie”

Cubby- Hey now Jimmie, my oh my what an interesting email you sent in. Be sure and hit up Brian for a sticker pack. Ask him about get’n some of our uber new micro stickers too.

So… you want to go really fast with an 8th scale buggy and have a budget of $70. Hummm… I could ridicule you here, but even I understand that there are people at every price point in this hobby.

I will start off by saying you are doing the right thing by attempting to buy new, not used. All those used motors are for sale on Ebay/CL/etc for a reason, none of which are good. I know a LOT of people that get rid of their old crap motors that way, on a limited budget the last thing you want is to get ripped off.

As far as 36mm motors go, yes, they can work in an 8th scale buggy when geared and used properly. The unit you listed I have never tried, so I can’t vouch for it, but give it a go and shoot us an email and let us know how it worked for you.

What kV should you buy? What gearing? What cell count??? To get the answers to these questions I can not stress highly enough that you use GearChart.com. Find it, use it, wear it out. Why should you do that? Because… unknowingly gearing your buggy for 212 mph will cause a fire. Even having it slightly too far overgeared will cause cogging, which is hard on electronics, and it will make your buggy harder to drive than it needs be.

You didn’t list what buggy you have (for its internal tranny ratio) , nor the size of your tires, so I have no idea what rough gear ratio you are working with, but you can enter that information into GearChart.com, along with some pinion/spur sizes & cell voltage, to get an idea of what kV you’ll need to hit a certain speed. Don’t ask others what your gearing should be, calculate it for sure over on GearChart.

Some general golden rules here, all of which you already know if you’ve been running high speed for a while-

1. Start by being geared too low. Like… shoot for 40 mph and work your way faster.
2. Keep a temp gauge handy. Yes, you might only be doing a run or two at a time, but at tall enough gearing even short runs can produce damaging temps.
3. Turn your brakes down as far as you can. Stabbing the brakes hard at 70 mph is Really, really hard on your electronics. Set them just high enough that you can get stopped in a reasonable manner, not on a dime.
4. Turn your steering down. A properly set up high speed vehicle needs very little steering, having too much can cause abrupt course changes that result in big (read- expensive) crashes.
5. Above all else, being “easy to drive” is imperative. Easy to drive means lower cell counts, lower gearing, and the best tires & set-up tuning that you can get.
6. High speed, just like most forms of racing, is about tires, tires tires.

Good luck Jimmie, and I expect another email from you in a couple months letting us know what kind of numbers you are busting out.

Hey, you made it to the end of another ASK Cubby, you are obviously core. Want some free stickers or a t-shirt? Shoot me your questions at Cubby at BigSquidRC.com. If you letter hits our front page you will get some free stickers or a t. You’ll probably never hear from me and more than likely your email will never hit our front page, but hey, why not give it a whirl.

YOUR Cub Reporter