100 mph RC8 brushless
 

Hi guys,

Ive been testing my friend's buggy for speed in past weeks, the best we got from it was 100mph,

we need a bigger pinion than 25tmod1 , if anyone know where i can get one or get one fabricated for me let me know!

We have tried 2 different 10S esc and they both had something wrong...
so we would need a slightly taller gearing, like a 28T pinion...

http://i193.photobucket.com/albums/z...i/PIC_2474.jpg

http://www.youtube.com/watch?v=lkiYmnRt3jA

Yes its a 2650kv on 6S... :lol:


thx for watching!

dude im trying to build a buggy to go 100mph, what set up are you using? specs?

that sucker smokes man, excellent work.

That's awesome. Nice work. And nice pics. And nice video... :lol:

i have the exact same setup i will have to try

And so the DUEL of the century begins...!!!

Thx guys! :)

I have no problem with competition hehe lol

We used a 25T pinion, custom fitted 34t spur gear, ofna foam tires and adjusted the suspension...

What lipo did you use?

It was a Lipoly 6S 30C, we will try 2 3S Thunder Power 40C soon, we know its a stronger pack it may push 1-2 more mph with luck lol

Wow, that's fast. Nice driving.

Those 40C packs will get you probably 105mph. What brand were you using?

That is fast....nice vid

In the vid its a Lipoly RC 6S 30c 5000mah

We will use 2 3S Thunder Power 40C 5000mah :)

Thx!

dude that thing sounds like a nitro when it passes! lol

Great job again mike you are the man to beat. You should post it on the ISC forum. Did you guys use a gyro for that run? What color tires did you use? Hey dwight will those plastic gears handle the power without stripping?

That rear wing has to add aerodynamic drag & unnecessary weight

also cool looks and saves the body in a rollover.


who asked about the wing?:neutral:

awesome work please keep posting OverrevO!

absolutely. it's just like running a plastic spur with a steel pinion, only reversed.

I've gotten very very close to 100 with my 8ight and the 2650 geared 45/25. i have a total reduction ratio of 5.95 because of a front and rear diff ratio of 3.3:1.

where as the rc8 has a 4.3:1 f/r ratio and with him geared 34/25 at a 5.86-he's just about 3 mph faster than my best run.

if i install the 43t spur i'm pretty sure i'll break 100 as that'll put me right at 5.68:1. I'm also ordering some of the kershaw pinions, but i seldom get to really go to a place to completely open the 8ight up.

Good job Mike for breaking 100 :party:

hey overrevo,
great looking buggy. i love it. can you post a link to the tires and wheels you have on there? i plan to do a speed project soon and those tires have obviously proven themselves. so rather than waste my time with tires shredding i just wanna get what i know works. thanks.

I think they are these.
http://www3.towerhobbies.com/cgi-bin...&I=LXKKF5&P=ML
I have a set for my 1/8 onroad project.:whistle:

all i need is the tires to open my mbx5 up.

Thx guys!!

thx for the pinion link thats awesome news! :yipi:


We had no need for the gyro, it go pretty straight the way we setup it.


The wing really have a role to play, run a buggy without wing and i guarantee you will lose control over 50mph, it will spin out. :)

We did changed the wing though, the stock RC8 wing had too much downforce and the buggy was lifting slowly the front end, we had no steering over 75mph lol and sometimes it was lifting slowly, that buggy is very controllable!

Its an ofna hi downforce wing that we have cut a part of the downforce...
just to have the right amount of downforce at 100mph.

Thx for the great comments guys!

Whats the best way to set up the toe in for f/r high speed. I wouldnt think you set it up like a you would on a track. I also am wondering since you have better gearing options now would it be better to switch to a 2200kv motor to lower the motor rpm.

We set the rear with a slight toe-in, barely, cant say the degree...i have no idea lol

we try to have the best contact with the road with the camber.
And the most important is to adjust them so its the same left and right, everything need to be very precise... if the car slightly pull left or right it will slow it down.

We will try the 2200 for sure, and may be the Neu 1515 1.5d too.


:)

Do you mean a real neu because I thought the nue 1515 1.5d and castle nue 2650 are basically the same thing.

50 kv more on the neu. but its a bigger motor as the cc neu is a 1512

The Neu 1515 1.5D is a ~2,700 KV 1515 and the CC Neu 2650 is based on the 1512 1Y.

OH!!!! boy I have been thinking the wrong thing for a while.

just tried my MBX5 with 19/46 gearing i got 69.8mph on 4s. im scared to go to 6s with rubber tires. should i get the belted ofnas or the foam ones?
can you show your spur gear mod?

btw i tried taking the wing off. it landed me a zero gravity roll into some ones front yard lol.you need the wing!

Foams ftw! lighter and able to with stand more speed. I find it hard to believe you got it too go that fast with rubber tires, they usuallly fly apart @ ~60mph causing a crash. How did you check it radar or gps?

I would definitely try the 1515/1.5D as I feel that will result in the best outcomes.

Also try heating your cells up to about 100-105*F before making passes. This lowers the IR of the cells and allows freer flowing energy.

Also,I would look for a set of the Losi Rally tires. This are good for 105mph for sure.

On the RC8, it is possible to change the F/R diffs out to buggy diffs with the 13/43 ratio? If so, I would go that route as it will be easier to gear for speed.

gps, got 71mph now but one tire blew out. im using majestic hooks but they are at the limit. also i was able to do wot so thats it for 4s. so what color dot should i get?

it depends. if you live in a warm climate, you can run with blue dots. if you live in more seasonal weather, go for the softer compound. where i live i can't use foams. there's too much dust on the streets.

as far as getting the 100mph mark, gear up to a 24 or 25t pinion.
the 2200 will get me to almost 95 in my 8ight geared 45/24-25.

after seeing Mike's 100mph run i dropped in the 2650 in and dropped to 43/25.
i didn't have my gps on, but i believe Mike's right about that combo. it's good for atleast 100. :gasp:

tires holding up is a whole other issue.


the losi rally tires good for 100+ (LOSA17768B) were discontinued indefinately.

i'm lucky to have 6 sets of them, which is what i use, but i also have used OverRevo's tire tieing method to use buggy tires to gain some gear and traction when i needed to.

the 1515 1.5D definately wil have the rpms, but i liked the 2650 better because the 1.5D created too much wheelspin for me.(even with the punchcontrol, it just has TONS of torque) my 2650 ran alot cooler for some reason too.

imo it would be kinda unecessary to swap the diffs when they make pinions that will be far more gear than the 2650 or 2700 will be able to use over at Kershaw.

Dwight have you tried those kershaw plastic pinion gears. Because I am not satisfied they will handle the torque. Bigger gears can handle more torque with out stripping because more teeth are engaged that why the bigger plastic spur usually hold up. I was also told by Nic case to use steel gears but maybe a mod 1 gear is alot tougher than a 32 pitch because of the thicker gears. You guys think a real neu 1515 1.5 d ,castle neu 1515 1y or 2 castle 1512 1y with 2 esc's on 6S each would be better in a slightly heavier gmaxx for high speed setup. Dwight didnt you have a twin brushless revo ?

i don't have any of the kershaw oversided pinions but there's a guy who runs alot down at our speed place that does. his is run on a 1515 1.5D with no issues at all.

I did run a twin neu 2200 MMM e-maxx, but it was far too much torque for the transmission. i turned 2 sets of diffs and 2 3905 transmissions to dust trying the twin combo.

in order to make it work, you'd need buggy diffs all around and a center diff.....even then, i think it would be very taxing on the drivetrain.

the 1515 1Y's i ran in my e-maxx were good for over 75mph most days with the right gearing and tires. it also had good temps. i could run nearly a whole 6S 8000mah pack without getting too hot.

personally, i think the 1.5D is too high a KV motor for the e-maxx for long running times on 6S. is it faster than the 1Y? yes, but for far less time imo. mine was good for 3-7 high speed passes before i had to let it cool.

if you're going for a speed record, and wanna go for broke i might go for the 1521 1D on 5S or 6S. on the same note, if you wanted a higher voltage setup, i might go with the 1521 1.5D on 8S or even a 1521 1Y on 10S using a MGM or phoenix HV-110. but i wouldn't recommend any of these setups for everyday running.

imo, the neu 1515 1Y is your best bet for an everyday high speed motor.

I have UE 8 spiders front center and rear on my e-maxx and a 1521 1.5y just sitting on the shelf.

SHAMELESS PLUG: I bought the neu off Nic Case! It's gone 140mph!!!

I just need a 12s esc and 2 6s packs..................... You guys have me thinking....................

i hope you atleast got him to sign the motor can. that's a piece of RC history! :yes:

As far as going for broke I would like to keep my build on a budjet. I also would like to use an off the shelf castle mmm esc on 6s. As far as making high speed passes I only can get one good run in probably 1000' of space. So I really dont need to run multiple passes. I have UE 1/8 scale diffs and I am sure my g-maxx will weigh less than a brevo. As far as the twin 2200 turning the tranny to dust Thats why I was thinking of running 2 less torquey castle 2650 mmm combos. So running 2 systems on 6s will work then with no sync problems?. I assume you geared it too the sky right? I will put the titanium gears set I have in If I need too. So the drive train I am not worried about. Tires I am getting some custom made ones from bsr put on 23mm wheels hex wheels. I am going to do my initial testing with the 15151y first and then step up to what will work.

there won't be any sync problems. i tried both neu sets with no success on the 3905 stuff, but it didn't really suprise me. however, twin feigao 8XL's were good.

the twin brushless neu setup with the UE diffs should be fine. I geared mine 54/24 and then switched to mod 1 and went to 36/22 with the feigaos. Still, in the end it didn't make me much faster than a single neu although it still had loads of torque.

Lube your tranny!!!!!!!! STP oil treatment? seems to work well. (search tranny lube) High speed failures to that tranny are due to heat and a little lube goes a long way (just like highschool)

I still say go dual. I want to see it!!

I wonder if 2 velineon brushless with 2 mmm esc's can handle 2 4s batts ? Dwight why didnt you should gear up higher and take advantage of the torque. I am sure it would of been faster. Thats some seriouse power with 2 sytems running on 6s.