My RC10GT to go brushless

[ginnz]

Hi there guys,

im just poking around here, looking at other guys RC10GT's, and thought id chime in.... First a little bout myself. Im mostly an RC heli guy, with all kinds of high end 450/500/550 and 600 sized brushless heli's, and starting to do the multirotor thing. I have a killer catamaran brushless boat I run on 8s as well.

I havnt been into the buggy/truck thing too much, but have a couple RC10GT's, and a couple OFNA Ulta buggy's. Now my Son is bugging me to convert my RC10GT's to brushless. I have a nitro one that i ran myself years ago, and was starting to build one up for my son. Its just a bugger to keep the nitro units running, and a real pain IMO. My son is 12, and it would be nice if he could just plug a pack in and run his truck.

Im looking for some advice here as to what size motor and ESC would be the best for us to use, and with that in mind. I have a dozen or so 2200 mah 3s lipo packs I want to use up with these trucks, so, they need to be able to use 3s as their power source. I have a spare motor here from my boat, that I was considering using, but on second thought, it would be WAYYY too much power for the RC10... its a 2075 kv brushless... more for the 1:8 Ofna 4x4... thats for another day.

I would like some idea's on the motor specs I should be looking at running. I dont understand the whole (T) rating thing... ie:17.5T etc.... Im prolly going to be ordering from hobbyking, so maybe someone can pont me out to an esc/motor right from there? I have bins and bins full of spare parts, and pinions, and will prolly order a bunch more gears. I plan on running the stock main gear, and slipper clutch. I bought a couple cnc made RC10GT brushless conversion plates, so the motor will attach right to the transmission, proper like, to avoid frame flex/mesh issues ive heard about from using DIY mounts.

so, with that all said, here is a couple pics of my truck, just the way it sits with the nitro motor still in it.... Ill start tearing it down shortly, and get ready to do the conversion. Ill take some pics of my Sons shortly, and add them in here soon. for now, here is mine. lmk what yall think! and any suggestions/info is greatly appreciated! and BTW, winter is just about upon us now, so I have all winter to do the conversions. theyll be ready for next spring/summer!

TIA,
Doug (ginnz)

[ginnz]

so no one had any suggestions as to what motor and esc I should go with??

[klavy69]

Its been a little bit on the slow side here as of lately. I know a few on the board has done this and its been talked about a couple of times so someone will eventually see this and chime in.

just an opinion that might or might not help...but as a basis for any crossover like this I'd either start with a Castle MambaMax or a cheaper chinese ESC of at least 60 amps for power. Might be finding more info in the 'R/C Tech Forum' section of this site found here.

Todd

[ginnz]

thanks for the reply. i'll add, money won't be an object... and ive been looking around at my options on flea-bay,and i just cant figure out what ill get. I mean, there are 6090 kv 5.5T, 7323 kv 4.5T, 3254kv 10.5T, 4370 kv 9T (you get the point)..... there are just too many choices. And I do NOT understand the whole (T) rating?? I get the KV thing, but whats with the T rating, and what should I be looking for in this in a motor for offroad bashing in the RC10GT?? My Sons truck will be quit a bit lighter than mine, so I may look for something thats not quit as extreme power wise for him, and it may be a good idea that i get something tamer for him, as he is quite young and doesnt have much experience... I want to build him a controllable rig, to learn and build confidence on.

My truck is quite a bit heavier, with the cnc aluminum wheels, and roll cage. I may also figure out a way to keep (part) of the second level deck, for battery retention, and to add stiffness to the whole rig, I dunno, it may just go though. So im prolly gonna put the sickest motor/esc combo in mine.

im also looking at ditching the dog bone drive shafts and looking for a better rear axle alternative to our rigs. I remember having issues with the dog bones popping out. I think there is an axle swap available? Im looking for the best, strongest, toughest alternative!

So, with all this in mind, if anyone out there has any more suggestions, and if someone out there could please explain the whole KV to T rating thing, id appreciate that as well! And oh... yeah, I received my aluminum brushless motor mounts today! and they are the typr that attaches directly to the transmission, perfect! Im running the aluminum transmissions in both rigs as well, so it will be tough enough to handle alll the power i can through them!

here are a few more pics of my rig..... as is, now.

[ginnz]

And, here are a couple of my Son's frame, this is what i have to work with, very similar to mine, minus the second frame deck, and roll cage. He has different swing arms, and shock towers as well.... Otherwise, basically all the aluminum upgrades are there too. When i'm done, these rigs should be real head turners, and a blast to bash around with!

[klavy69]

Yeah, there should be some info in the tech section I posted about the brushless stuff. The T (turn) rating and the kv was always a confusing point to me too. Why not just keep it all the same to make it easier but thats just my whine.

As far as getting rid of the dog bones thats an easy one. Get some MIP CVD kits for your gt's Depending on what you have for axle sizes anyway between 3/16" or 1/4" drives. Not sure what you have in yours. Willing to say you have 1/4" in yours yet which wouldn't be too much of an issue but since you have alloy wheels and pry want to keep them you'll have to figure out what you have. Otherwise you can pick the CVD kits up off ebay and some online hobby shops pretty affordably yet.

Do some reading in the tech section and you might find some stuff you are needing for info. Good luck and hope you figure it out.

Todd

[RC10th]

Generally sensorless brushless systems are rated in KV and sensored systems are usually rated in turns (same as the old brushed motors).

Sensored systems tend to be smoother so I would look into getting one of them. A 10.5 or 8.5 turn would be perfect, with the 8.5 being a little quicker. This is the best balance of performance and run time. I personally like the Hobby Wing stuff, good quality at a good price, easy to use and very tunable.



You can put so much power through your GT that it is totally ballistic and uncontrollable, but remember too, this can make your truck less fun.

[ginnz]

Great, thanks guys! Ill convert my trucks to CVD axels, should be no problem, and ill set my son up with a slightly tamer system, and as his truck is lighter, it should even itself out pretty much. And ill look into the 8.5-10.5 T stuff, its a good bit of info to start! I seen a 9T 3 in 1 combo, its a hobbywing Ezrun, i think ill get that for my boy, and maybe a Castle Creations Mamba Max SCT Pro speed control with 2400 kv motor. Its a sensorless motor, but CC is good stuff, dont think itll be an issue..?

either that, or im looking at the CC mamba Max pro SCT with the Neu-castle 1410 3800 kv... not sure which one would be better.

Anyways, I got some stuff to work on now. Ill strip the rigs down, and start on converting tyen axles over, and get on ordering some power systems.... This will be an awesome project for me and my boy over the winter!

Pics to follow, thanks again guys!
Doug (ginnz)

[RC10th]

Check the ESC specs that come with the combo, if it's the 35 amp version it's probably not heavy duty enough, if it's the 60a your fine. Also the Hobbywing 9T EZRuns are a 380 size rotor.

The SCT pro combos for your truck will be plenty if not too much. The 2400kv will be more tame while the 3800kv will start making things nuts. I'm sure they are 4 pole motors which generate a lot of torque. 2400kv is pretty low considering the 9t hobbywing is 4300kv, but the extra torque allows you to run a much taller gear ratio to make up for it.

[ginnz]

thanks, thats good info. Im looking at a 60A esc for my Sons truck, and 80-100A for mine. i think Ill look for a 2400Kv for my Boy, and go with the 3800Kv for mine. I want to upgrade the axles to the best I can find, as I dont want issue's with the driveline. We have all new aluminum transmission housings and brace's, and all the gears and bearings are upgraded. Im hoping after i strip all the nitro stuff off mine, it will shed alot of weight, as mine is awful heavy Im also thinking of trying to use 2 - 2200 Mah 3s 40c packs in them, if i can figure out how to get them in there. Im hoping i can mount one on each side of the frame, to distribute the weight. If its not going to work, Ill just buy a bunch of new 3000+ MaH packs form hobbycity. Its just that i have a dozen or so of the 2200 MaH packs from my 450 size heli's, so it would be good to use them up. i just think 2200 mah is a bit small, prolly wont get more than 5 min of run time off them? Anyways, thank you all again for your tips!

Doug (ginnz)


---EDIT----

Well, i'll be. I just dragged then trucks inside my office and got them on the bench, i thought id start tearing them down, and low and behold, ive upgraded the driveline from the dogbone's to the CVD setup already! And going the the multiple bin's of parts, I have two complete new bearing sets, new tranny gear sets and another couplebags of MIP CVD rebuild kits. man, I have parts. Im looking Integy shock rebuild kits, as a couple shocks seem blown, as the damping is non existent. They just spring. i replaced the oil, and it didnt help. Maybe ill just source out some new big bore shocks. The ones I had on my Xray 808 sure were nice!

well, andyways, thats enough for one day. Now I guess ill break the bank and get the power systems. I wanna build the sickest, most rippin' truck! Me and my boy have a great place to build a small track right off our yard too! Its got natural terrain for some nice jumps, and some nice straights. Gonna be a blast!

[yellowdatsun]

I think the lack of replies is because there aren't many people who convert the gas trucks to run electric. Most people just buy an electric version. It's one of those situations where you'll likely have to figure out much of the conversion for yourself. A lot of my projects go that way......I'll ask a question, and get no replies.

As for the T and Kv ratings, I was confused as well. Back when I left the sport many years ago, all we used were T ratings, so the whole Kv thing was new to me. Then trying to convert one so you can relate it to the other was another issue. Though all of the conversion charts I found don't really seem to make sense. Like it says my rather cheap Castle setup is equivalent to a 10.5T motor, I dunno, that just doesn't seem right. But I guess it is.

Anyways, as I'm sure you found out, The higher the Kv, the lesser the torque and higher the max rpm. The lower the Kv, the more the torque and lower the max rpm.

The T ratings are rated differently, since I don't remember the old motors had rpm ratings, but could be wrong on that. Way back when I just remember that we knew the lower T ratings meant a faster motor, and a higher T rating meant a slower motor.

I think technically now it goes: The lower the T rating, the faster the motor, and lower the torque. The higher the T rating, the higher the torque and slower the motor.


Sooooo, with a big rig like what you have, you'll likely want something in the middle. With my Traxxas Slash I run a 3800kv Castle motor, and my Associated B4 buggy runs a 4600kv Castle motor. You'll want something closer to the 3800KV range. The 4600kv is rated as a 10.5T motor, the 3800kv motor is rated about 12T, and probably more appropriate for your RC10GT. The Mamba Max might be too much for it. Even with the 4600 motor in my B4, I have a problem with wheelies. Sure it's kinda fun if you're just playing, but if you want to do anything at the track it's not a good idea. The mamba max is a good choice for the big and heavy Slash 4x4.

[ginnz]

Heres a little update. Ive stripped all nitro stuff from the chassis and started to fit the brushless motor adapter plate to the transmission, because im using the aluminum transmission case, one of the stand offs used to attach the plate needs a little modification, no big deal, i just need to do it. And im thinking of keeping the top frame plate that houses the steering servo. Im just going to cut it down a bit, and reshape it as needed. The ESC should dit under the front, kinda protecting it, and the battery's may be held in some how with it, im not sure yet. Im starting the conversion on my truck first, and my Son will do his this winter. Im going to get him to do it himself, with my help. If he wants to "play" with this hobby he needs to learn how it all works, and be able to fix some stuff himself. Itll be a good little project for him to learn on! Anyways, here are the pics...

[ginnz]

Im thinking of getting this ESC/Motor combo for my truck, its the Sky Toro Ts 120A ESC, and Sky Toro 3650 Brushless 4-pole 3500kv motor, and program card. It should be plenty for my rig. The 120A esc should give me all the room I need for anything I can throw at my rig in the future. What you think of this setup? Any idea's on what pinion size i should run with this setup? Ill be using 3S batterys, so keep that in consideration.

[yellowdatsun]

Never heard of that brand, so as a result, I personally wouldn't use it.

[ginnz]

Oh jeez.... ok, well you know what, I may just heed your advice. I dont know what brand I should be looking for. I just looked at the specs and the esc looked good. It's 120A, can handle 3S and has alot of programming features. The motor just looked like about the right KV rating that I am looking for. Back to Ebay, I guess.. Maybe HobbyCity..

Thanks for the heads up.
Ginnz

-----EDIT

Actually, I did some research on the ESC, and it turns out the reviews were all very positive, so I am going to take a chance and order it for my truck. I dont know if thats the motor Ill try yet, as i can get it as a package, or the ESC alone. But I will try the ESC. I may get the bluetooth module as well as the PC link. It will be a wjile before I buy the stuff, But I will keep this updated.

Ginnz.