Slo-V Flyer

I know about the 8 or 9XL + MM esc combo on 12-cell nimh is good for running in the E-Maxx, but they're outta stock for the 8 and 9XL motors at unitedhobbies. Unless someone has another link, I was wondering if I can get away with a 9L 2730kv motor on 14.4v 12-cell IB 4200s? I know the Mamba Max esc can handle 12 nimh cells without needing to remove the red wire and using a receiver pack or UBEC (don't want to spend any more money than I need to), but I wanted to know if I low gear it enough (like 13/72) or similar, would it work out ok? I'm not looking for blazing speeds, since it'll only cause more damage and cost $$$. I just want it to go maybe faster than stock and of course not worry about wearing out brushes and heat issues.

Also, if someone knows where I can get metal idlers for the E-Maxx that would be great, because I think my stock ones are going with just the stock motors and Ib4200s. Already have MIP cvds in the rear after the one left u-joint twisted off.

The motor I'm looking at: [link=https://www.unitedhobbies.com/UNITEDHOBBIES/store/uh_viewItem.asp?idProduct=4882]Feigao 540-09L 2730 kv[/link]

Also, I was thinking about this one. since it uses the standard 1/8" shafts: [link=https://www.unitedhobbies.com/UNITEDHOBBIES/store/uh_viewItem.asp?idProduct=5346]Feigao 7L 3500 kv motor[/link]

I want to run these on 14.4v 12 cell IB 4200s or similar, and I am assuming the MM esc can handle those volts without any mods (beside a fan maybe).

Slo-V Flyer

If I do get the 9L, what pinion size range should I get? I looked up on rc-monster, and the smallest 5mm shaft pinion they have is 14 teeth and up, and never mind the ridiculous $12 price tag, is that a safe bet with say, a 66t or 72t spur gear?

Slo-V Flyer

Ok so I guess I'll order the 9L 1/8" shaft from offshoreelectrics.com, and try it with 12 nimh cells on my E-maxx. United hobbies is in Hong Kong I just realized, forget that, it'll take too long for it to get here and never mind the shipping cost.

If nothing else, I can plug the 9L into my Rustler with Masher tires for long runtimes on 6-cells nimh, to putt around the dirt.

happywing

I'm very familiar with the Mamba Max when used in 1/8 buggy conversions. Not so much with Monster Trucks. I run the Novak HV-Maxx 6.5 in my Gorillamax G2r Revo and it's all the speed/torque I need. That said, I'll help all I can:

- You will need a UBEC to run 14.4 volts on the MM
- Mod1 pinions with 5mm shaft are available at Tower for $7.95 [link]http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXMGY8&P=7[/link]
- I wouldn't use a 1/8 shaft if possible, but it hasn't caused me any problems on my E-Revo
- RC-Monster has metal idlers

Sorry, I can't recommend a Feigao motor. I don't know much about them other than the fact that several of my friends have problems with them. They overheat and fall apart.

Finally, you better think about much more than just idler gears if you want to go faster than stock with an EMaxx. You need:
Robinson Slipper Kit
Steel Idlers
Hardened differential gears
Front, Center and Rear CVD's

I would also recommend converting your transmission to a single speed.

Slo-V Flyer

Are you sure I'll need UBEC to run 12 cell nimh? I thought Castle's website says I can use 12-cell nimh/2-3s lipo? Yes I know 12c nim is 14.4v and 3s lipo is 11.1v. Damn, if that's the case (can't run 14.4v un-modded), can I simply use a 4-5 cell receiver pack and remove the red wire from the ESC->receiver plug?

I'm trying to stay cheap on this if I can, and UBECs don't come quite cheap (as in aren't they over $30?) from what I've heard.

Thanks, I saw rc-monster has metal idlers, and I'm already running CVDs in the rear axles for now (break->upgrade as I go.. ). As I said I'm not looking to go too much faster than stock, but at least low maintenance motor performance rather than have to buy new Titans every few months or so, plus the Titans I have right now start to heat up more as they are getting old.

About the shaft size, think it's silly to pay $12 for several 5mm pinions just to find I only need one of them to run right. And since I don't abuse my truck like some may (no crazy jumps and stunts), I think I should be ok (though I've seen a broken motor shaft of another user here earlier).

I understand the Feigaos may not be top notch, but several members here seem to be ok with them in their E-Maxxes and such, so I thought hell I already have the MM esc, why not jump into it and get a cheap BL for my Emaxx? Like I said, I might just pop the 9L in my Rustler if it turns out to be wrong for the Emaxx.

Thanks for your input. [8D]

rschoi_75

Yeah the UBEC from rc-monster is a good one. You will need it for anything running on 12+ cells or 4s lipos. If you can wait for the Castle Creations ubec, then I would do so. It may be another month or two... If you want to use your receiver box, that's fine, but a ubec will cut down on the weight.

Regarding the Feigao motors.... here are some dealers who have them in stock:
- RC-Monster: http://www.rc-monster.com/proddetail...WAND_XL&cat=20
- Fine Design RC: http://www.finedesignrc.com/motorsnemesisblue.asp

The 8XL or 9XL are fine choices. If you e-maxx is on the heavy side (12+ lbs) get the 9XL. If its lighter you can get the 8XL. DO NOT buy a "L" series motor for your e-maxx. I know lots of websites claim they work well, but they run extremely hot and will burn out long before the "XL" series motors do. Now, the "L" series motors are great motors, but the e-maxx is a little too heavy for it (IMO). Please don't think I'm just bashing the "L" series motors...they just don't belong in anything over 8 lbs.

Slo-V Flyer

If running a receiver pack will work ok, then for now I don't care about the slight increase in weight. I might get a UBEC later on.

However, I kinda already ordered a 1/8" shaft 9L motor from offshoreelectrics.com well before you posted......Doh! One of the reasons why I didn't order a 5mm motor or XL for that matter was that I didn't want to go through the hassle of buying expensive $12 pinion froms rc-monster just to find out which one will work... Kinda' silly I know but well I took a chance, lets see what happens. Heck I'll just slap in my Rustler and drive it around on Masher 2K's or something to use that torque if it overheats in the Emaxx.

BTW, my EMAXX is pretty much stock except for the rear alloy bulkhead and rear mip cvds, and HS 5645 steering servo. So I'm hoping it's not too heavy. I might have to invest in some lower profile tires to help with the weight though.

rschoi_75

yeah, just slap a fan on your motor and gear conservatively to begin with. If all goes well, you can gear lower to match your needs. At least these motors aren't too expensive.

Slo-V Flyer

Haha! Yeah I am gong to start with 13 (?) /72 gearing that I have at the moment for some wheelie fun using the Titans. Yes good thing it is relatively cheap ($68 shipped). I have a 540 sized heat sink I'll also use just to be sure, though if things work right, I shouldn't need it, but we'll see. It is almost 1000 kv higher than the 9XL, so I'm hoping I can gear low but still get good speeds.

rschoi_75

oh and I forgot, use some thermal epoxy like Arctic Silver or Zalman's paste in between the heatsink and motor. This will help in the transfer of heat from you motor to the heatsink. It will actually lower your running temps by up to 5 deg F.

RURC

Come on guys how about 6 of the 20mm Feiago motors in a radial pattern around the spur gear. 6 Mamba 25 esc's. If you run them off the same battery it should be smooth and fancy free.

Ok its late and I'm tired. Good night.

BackFilp 360

i hope im not late but you dont need a bec for 12 cells its only on 12+ so 14 cell you need one

Slo-V Flyer

No it's not too late, I have only ordered the motor so far, and don't plan on a UBEC until next month or something.

Are you sure I don't need a UBEC to run 12 cell nimh 14.4v in the Mamba? Because I know I've read people using UBECs for 12 cells and usually with 4S lipo which is 14.8v, but I'm guessing they are doing that "just in case."

Yeah I could hook up my Mamba 25 and 4200 kv motor, and then 11 more of that combo to my Emaxx spur and watch it go. That would be fun. Always wanted to do something like that, but instead of radial, in a "V" pattern, so that I could claim it's powered by a V12....

RURC, I'm taking it that you mean the 9L will not be suitable at all? Or you are just drunk on sleep....yeah.

rschoi_75

or 12 of the 12mm feigao motors...? lol...

RURC

I ment exactly what I said. But now I like PVT PILE and the 12 x 12 set up.

Slo-V Flyer

Hmmm 12x12, yeah that would work better as a V-12 because I would have enough room with those tiny motors. Ok but seriously, I'm hoping the 9L will work.

rschoi_75

lol...didn't know you were being serious... If anyone is crazy enough to try it, definitely post pics.

RURC

PVT PILE -
That was directed at Slo Flyer. I was kidding. Like I said it was late and I was looseing control.

but the V12 sounds cool. But I think we should try doing to Audi thing with the W12

Slo-V Flyer

Well, actually, I thought about doing the V-8 or whatever thing with those tiny micro motors used in Zip Zaps... just to see what kinda crazy power could be had out of it. In my mind I pictured an assembly that would hold 2 banks of micro motors in a V engine configuration, all turning a main shaft, much like the crank shaft of a real engine, which would then turn the "actual" spur/bevel gear of the r/c's transmission, either a car/truck/boat, or even a direct drive plane prop.. Why "V" and not straight? Because the term V-x sounds more technical, and it would look mean too.

The motor has been shipped, so I should be getting that hopefully this Monday or Tuesday. Till then I gotta get my lazy self to replace the (hopefully only thing) noisy idler gears with new ones. I was thinking, I should at least replace the 1st gear idler with a metal one, since that is the one that "feels" the most torque... or at least that's my theory...though I think it's smarter to just save up and do both eventually, if that Feigao 9L works out better than the twin Titans.

rschoi_75

wouldn't it look more like a C-"X"... ("X"= # of motors used, and C= circle)???

ok, sorry, I'm going off on a tangent. Its Friday and I can't get my head into working today....

Slo-V-Flyer: good luck on your build.

pythonfan

My Feedback: (1)

ok my comp is messing up and will only show me the first post, but i have the same set up but on my e-zilla, any of these combo's will work 7xl-9xl i have the 8 xl and is offers a good low end with still having the wheelie poping torque.

Slo-V Flyer

I just got the 9L in the mail today! That was fast, ordered it Wednesday, and and got it Saturday! Ok I know it's the shorter can, but I got it mainly because it's 1/8" shaft, and I wanted to keep it cheap and not pay $13 per 5mm pinion if I got the XL version. While I was at work, I ran all sorts of numbers in my head using a calculator, and came to the conclusion that as long as I keep it geared right, I can have enough power with 12-cell nimh to go at least 30mph if not faster. The 9L can handle 68 amps max, so thats 68x14 volts = 952 watts

My only hold up is some Deans to make a Y battery harness for the MM esc and some connectors for ESC->motor. Gonna get that tomorrow or Monday from the LHS, since my work hours keep me busy.

Hmm....

Slo-V Flyer

Alright! I couldn't wait for everything to be setup till Monday, so I did a little test. ;D

Hooked up my single 6-cell IB4200 to the MM esc, installed the motor and 12t pinion with 72t spur. Since I don't have the motor connectors yet, I just poked them into the MM esc's connectors, hoping for just enough contact to do a quick stop-go test.

It worked! The connectors were kinda loose of course, but jiggling them enough made them hold up to a short forward backward test. On my half used IB 4200, and 12/72 gearing I can just make it pop up the front OR rear end. Of course I did this test in my living room, so there is no space to judge its speed at all, plus I didn't want to risk damaging the ESC due to the bad motor connections.

This means I should get plenty of performance on 12-cells once I make the "y" harness for dual batteries. I'm hoping Castle will respond to me email by Monday about whether or not the MM esc can be used with 12-cell Nimh without the need for an external BEC. Otherwise, I'll just run it on 6-cell Nimh and see how it goes until I order a UBEC.

Hopefully my LHS stocks the proper connectors I need to match the Mamba ESC's. The Mamba Max motor connectors are 5mm right?

rschoi_75

The MM uses 4mm bullet connectors. If you can't get them from your lhs, you can get them at lots of online dealers. Off the top of my head, I know that Tower and Starluck RC have them in stock.

And I think that castle will suggest that you use a separate bec w/ the MM on 12-cells. I have a very similar set-up on my e-revo and a separate bec really helps.

Slo-V Flyer

Damn, I was hoping I could get away but seperate BEC it is then, huh?. I really don't feel like waiting another few days for that or the connectors to arrive. Hopefully the LHS will have the 4mm connectors so I can really see what thing can do, and maybe an airplane BEC, since they carry lots of plane stuff too. Ok so for seprate BEC I simply remove the red wire from the ESC -> rx connector right? I know I've asked before, but I wanna be sure before blowing my $150 ESC. I'm thinking I'll buy a servo extension, plug my ESC into it, and then remove the red wire from the extension, so that I don't mess up the ESC wires.

BUT just for kicks, I ran it again for a good 10 minutes from a fresh charge. Same gearing, on a SINGLE 7.2v IB 4200, pops wheelies in 2nd. It goes slow, of course, like something around 10mph in 2nd. Haha. The best part is (not recommended) I don't even have connectors soldered onto the motor wires, and it showed when ever I gunned it in 1st, it would sometiems hesitate as the connections weren't letting the amps pass through.

But it can crawl up the curb on low throttle, with some slippage (motor stutter at very low rpm understandably). At 50% brake setting, even at those low forward 1st gear speeds (like 4-6mph TOPS, it'll flip it on it's back! I had to dial the brakes down using my Tx's throttle "low" ATV so it wouldn't flip. The EVX + dual Titans couldn't even come close to the braking (and breaking that will happen unless I tone down the brakes to like 30% or something).

According to my DTX temp checker, the motor reached >120'F, and ESC was a few degrees cooler, batteries were hot from the charger to begin with, but stayed around 110'F. Batteries after this are at 8.0 volts. Yeah I definitely will have a wheelies popping machine on 12 cells just as soon as I figure out I do or don't need a UBEC for 12 cells for sure. Hopefully I'll hit the LHS on my way to work and get them Deans and some 12g wire for a Y harness.