d.k.v

hi guys
i got my vxl waterproof today and im wondering if i need to do the set-up again?
and is there any run in procedure?

thanks
matthew

Skunkworx

Nope, not with the VXL. It doesn't have any calibration, so you just plug-n-play. You do have to set it for LVC and for the mode you want to run, but that's about it.

d.k.v

ok. just tryed it.with half batt (1500mah 7.2) it was as fast as it was with the xl5. needs lipo...
with a 3s lipo what speed should i get?

CarGuy7a

You will need to calibrate the ESC to your radio system. 3s lipo will make it insane. 3s also produces alot of motor heat. For just normal bashing and sport driving you want 2s. I have 2 2s packs and one 3s. My truck sees the 2s more because they run cooler and produce enough power to have fun with and not worry about cooking the motor. Plus I have to re gear the truck lower for running 3s to keep temps manageable. I only get the 3s out when I want insane speed.

d.k.v

just went a full batt(1500mah 7.2v) and its insane compared to stock...
so what will 9 cell then 2s lipo bring?

Skunkworx

9-cell (I'm guessing you meant 8 cell though)would be at roughly the same voltage as a 3S Lipo. It would give you 12V fully charged if I'm not too far off on the numbers, but the big difference will be the punch. A 3S will give you more top-end because it packs a tad more full voltage than the NiMh's will, but it also maintains the voltage better. At full depletion, the 8 cell will be at 9.6V, a lipo will be at 11.1V, so the speed will stay higher with a Lipo (on 3S that is). It will do the same for the 2S as well, but the lower voltage will mean you go slower. An 8-cell NiMh will almost always outrun the 2S unless you are running crappy cells. You could gear up higher on a 2S, but you have to watch your motortemps! (and the battery as well)

You can run 3S all day long if your gearing is correct. Just make sure you check the temps every now and then. If it's consistantly below 140-170, you should be just fine, but most prefer to stay around 130 or less. Just drop a tooth or two off the pinion if your temps are too high until you can keep it in a manageable range. Same thing goes the opposite if the motor is cold. Add a tooth or two to get more speed, but watch your temps. Also, the longer you run (the bigger te battery), the more you'll have to watch your temps. Heat doesn't just go away on its own, so if you build up a bunch, you have to let it cool off between runs or keep you speed down to avoid overheating.

Your top speed has a lot of factors, so it's tough to say without knowing what your setup is. Typically it'll be fast regardless of what truck it is once you get up to 3S or more, but uite a bit of it could be your gearing and roll-out of your tires. What car are you running with? What tires? What motor Kv/turn? What pinion? What spur gear? The list goes on and on.

Skunkworx

I stand corrected. Finally figured out the calibrating part a minute ago. Easier just to send you to the site to watch the video than to bore you to death with the explanation. Here's a quick link: http://www.traxxas.com/products/video/support/

d.k.v

thanks.
its just a slash with a brand new waterproof vxl,3500kv/10turn,stock tires and 18/83 gearing.
motor was room temp when i just ran it on 7.2 1500mah
so 23t pinion?

do mah affect accaleration?

Skunkworx

In a way, yes. mAh refers to the overall size or capacity of the battery(think of it like a bucket of electrons. Bigger bucket makes it run longer). However, the bigger the battery, the more current it has naturally available to it. TheC rating refers to the current output capability of the battery. Let's say there are two batteries, both are 20C. You take the C and multiply it by the battery amps (so 5,000 milliamps = 5 amps). 5A X 20C gives you 100Amps. Theother battery: At 4,000mA, you get 80Amps. So to answer your question directly, yes. It can play a role in your acceleration. But that's more reliant on your overall C ratings than just the naturally aspirated higher amps due to the size of the battery. Put it this way, the higher the C, the faster it'll get up and go(plus the battery will stay ice cold). If you bumped that 4,000 up to a 30C, you'd be able to yank 120amps out of it and out-do the 5,000 easily.

Amps don't make it go any faster as far as top speed goes (at least not necessarily), but it will give you more instant torque, therefore making it quicker off the line. You could gear it heavier and still maintain the same off the line speed,whileattaining a higher top speed as well. BUT, you could alsomaintain a higher speed (on the original gearing)if you had more amp delivery capability because the motor can wrench harder at higher speeds. (sorry if all that sounds confusing. Easier to observe it than explain it I guess?) You just have to have it set up in the right combo because the 4,000 could easily stomp the 5,000 depending on the setup. See what I mean?

The Voltage is what dictates how fast the motor will spin, and then roughly how fast the car will go (*must take into consideration gearing, rollout, blah blah blah...). Say you're running the VXL 3500. That means you take the Kv rating of 3500, and multiply it by your voltage (**this is theorectical at full voltage)(guess you'd have to convert turn over to Kilo-volt ratings to figure your motor though) . On 2S, that would be 8.40V, on 3S, it would be 12.60V. So, respectively, you'd get motor speeds of 29,400rpm's and 44,100rpm's (a 14,700rpm difference). That's just an illustration of how the motor speeds and voltages can affect your overall speed. The downside is that the more speed, the more heat. Higher heat means lower efficiency and all that happy jazz. So, depending on what you want to get out of your car (speed or off the line), you can get a motor that will suit your needs without having to change too many otheritems on the car. Is that wht you are trying to get at? Purpose building it?

d.k.v

im trying to get it to climb the sand hills where i bash.very soft sand. its runs out of folward momentum half way up the hill. so now with my new vxl it should get up there.
and i bash with my dads hpi baja 5b. i corner faster but he blows me away in any kind of straight line.
im trying to get this thing fast but still be able to climb hills and do parking lot bashing without changing gears.

what kind of c rating do a cheap nimh batt have?
so i guess i need a 35-40c 2s 5000mah lipo??

RHarding

My Feedback: (3)

This is a question for anyone out there. Where can I find small rubber grommits? I need one with a 1/16" ID and one with an ID the size of a 4-40 rod.

Thanks

Richard

Skunkworx

All you can do is play with the gearing and watch your temps. You won't really have a "best of both worlds" kind of thing. Usually you get speed or you get low temps, but it's hard to find a combo that will truly do well in both climates without swapping pinions. You can reasonably do both if you either lay off the throttle in the sand, but that's hard not to do because you lose all the speed.

If you went 3S, you could gear down a bit and maintain the speed as well as the temps.It's just a matter of finding that sweet spot. I would just plan on running under heavy load settings and deal with the loss of top-end to save your motor. On 3S, you'll almost never be lacking in speed anyways.

NiMh's usually carry a 5-18C rating depending on the manufacturer (lthoughit's never really given on the package). Lipo's on the other hand do, because that is their big claim to fame.They deliver the same exact electrical power as any other secondary battery, they just give acrap loadmore of it! A standard 25C pack should serve you just fine.I think most 1/10th scale ESC's use a max of 100 amps, so if you had a 25C 5000 (that gives you 125Amps), that'd give you over the maximum amps the ESC will use, so you will never feel like it's running out of power. As the pack ages it helps to have a higher C, but my 25C's are still kicking pretty good after over 100 cycles. A couple of them are almostr 3 years old now.

The good thing about getting a 35C+ is that it will run virtually just as hard at the end of the pack as the beginning. Like I said though, you pay big bucks for those higher C's and you probably won't need them if you are just out bashing and having fun.even if you were racing, you'd hardly notice it unless you were in a highly modified class where they cheat on everything....er, I mean they just bend the rules a little!

RHarding-are you talking about O-rings, or wide grommets? I'd check with Gainger or McMaster-Carr. They've got tons of stuff like that but you have to be a bit more specific with what you are needing. Your description seems a bit too vague to me at this point. Sorry I can't answer your question right away.

d.k.v

thanks skunk. ill get some diff pinons when i get a 8cell battery.and just 'play around'

Skunkworx

Cool beans. Just try to work your way from stock. If anything, you want to lower it at first to keep it from overheating. Take it slow no matter what you do with it. Have fun!

Hibityhupla!

i had put the velineon brushless set in a cheapo car to see what it would do also....stock the car did 20mph...with the new set-up it did 27mph(on same 7.2v 1800mah battery)..with a 3300mah 10.8v stick(9cell) it pulled 38mph...on a 2s 7.4v 3600mah lipo it did 41mph and on a 3s 11.1v 5400mah lipo it pulled 49mph....all on same gearing(strange car, had 1m gearing..only way to play with that is a motor with a 5mm shaft) all speeds were done with a bushnell radar gun...if you play with gearing you can make that thing fly... i would stay stay around 50mph or under just for bashing...any faster and it will get harder to control....mine was all done to a 1/10 on-road...yours might be quicker

TIGER76

8 cells great m8 tons of fun then you try lipo and cant believe the difference in runtime and power !!!
If you get some 8cell packs get some big mah on them i run 4600 and 5000mah and get about 25mins full pelt,Careful with 9cells packs the esc only reads upto 12.4v or something and if the batteries charged abit higher it errors sometimes,but 8cell will get you around 50mph geared 28/83

I tried a friends 11.1v traxpower lipo and instantly ripped a rear tyre off [] so 8 cell will do for now

Little tip only gear high for speed runs or smooth areas running trying to run major offroad or long grass will overheat the esc and something will melt ( like my solder connection [])

Redvanmafia

you should never need 28/83 to get 50mph, my losi excelorin 4800 greared 18/83 gets 60mph easy at 75% throttle (with low settings) i cant put it all the way down or it rolls back on its roof, i need to mess with the rear wing to give it some up force instead of downforce witch at high speeds brings the nose up, im going for 70mph 18/83 is tight i think i'll go with 20/83 and a heatsink on the motor 70mph will be easily attainable, This is with a 3s lipo 60mph is confirmed by riding the passengers seat of my buddys car on a smooth long back road 100kph (a little over 60mph) it would lift up and i would loose it,

d.k.v

thanks guys
on the back of the pack it says it will handle 9cells. but ill start with 8cells

hey Redvanmafia good luck on getting 70mph

Skunkworx

9 cells would be a hair higher than a 3S lipo full charged (13.5V -VS- 12.60V). Not sure why you would say the ESC can only 'read' up to a certain voltage. Maybe you meant it was rated up to a certain level? Depending on the ESC, they can actually handle up to a 4S Lipo if needed (that's 16.80V fully charged or 18.0V if you had the full 12-cell NiMh hooked up), so both 9-cell and 3S would fall under that number by a fair margin. The motors usually can't handle all the speed, so that's why you don't see 4S as an option usually.

Redvanmafia

9 cells will be higher technically, but a 3s is lighter, will have more punch, and keeps it till it dies, doesnt fall off like that 9 cell will

d.k.v

kk. 9cells is only 10.8
each cell is 1.2v x 9 cells = 10.8volts.

on another note. i cant get her to wheely.. at all.
even if i pick it up and lean it on the rear bumper and gun it the let go and it just drops straight to the ground insted of driving down the road on its rear wheels.. it did with the xl5.
so whats up with it?

Hibityhupla!

at what voltage? a 3s lipo should give you more than enough to flip that thing if the tires get traction

Skunkworx

That's the rated voltage o the cells. Fully charged they are at 1.5V per cell and you end up with 13.5V, which happens to be .9 volts higher than a 3S Lipo. The difference between the Lipo and NiMh is the Lipo will give you a crap-load more amperage (usually. Depends on the C rating and capacity). What Lipo are you running compared to the NiMh's anyway? Sounds like you have junk cells of both kinds if you can't get it to flip over backwards. Unless you have your gearing insanely high, it should be able to kick hard enough to just about tear the car apart on those power systems. Put it this way: Buddy of mine had his E-Rustler with a 27t pinion; stock spur; regular tires; and he couldn't keep the front end don on the car at almost any speed. Granted he ended up cooking his motor the next day, but the idea that either of those batteries not being enough sure sounds you got something extremely jacked up on that car for it to not scream like a banshee.

Oh wait, just read you are using an XL-5. That's your problem. It's only rated for 2S or 6-7cell. Besides that, it can't deliver the goods like the bigger XL-10 or VXL can, so I'd ditch that thing and get a brushless if you want it to rip. It'll be impossible on a stock system.

d.k.v

you read it wrong... or i wrote it wrong

with the xl5 it would wheely
but now with the vxl it wont.

i only have a 1500mah and 3700mah 7.2v nimh batts

TIGER76

How tight is the slipper dkv? i know the rustler/pede chassis will wheelie on 6cell with vxls but not sure on the longer slash chassis tbh either tighten the slipper more if you can or add more pre shock collars on the rear etc

And i know its gonna sound dumb but your not running it in training mode are you? ( 3 blinking lights)