Brushless Savage Help
 

Hey everyone,

I have been running a BL savage for a year now, and only today found this forum. I did the conversion myself, and shoe-horned in an E-Maxx tranny (with steel idler gears), and a Novak HV-Maxx BL system. I'm running it on
12-14 cells in a brick format:

http://putfile.com/pic.php?pic=6/16919123358.jpg&s=f5

The truck is running 6.9" Imex K-Rock tires, and an ulgy Parma Garbage truck body.

http://putfile.com/pic.php?pic=6/16919221236.jpg&s=f5

Lately I've been having a tonne of glitching, overheating, and cogging issues with the HV-Maxx set-up, and am such am looking to upgrade to a different and more powerfull BL set-up.

I've read a tonne of posts on this forum, and it seems that popular choices are BK/Feigao/Wanderer XL motos in either 9 or 10 turn forms. Is this a good choice for 12-14 cells?

I'm looking for something that will definately out perform my HV-Maxx set-up, without being undrivably insane. I like to go fast, and wheelies can be fun, but most of my driving is off-road bashing. I'd like a good all around setup that I can bolt up to my current E-Maxx tranny.

For an ESC I was thinking of either the BK 12020 or 9920.

Any assistance or direction would very much be appreciated.

Thanx!

I think the Warrior 9920 or Quark 125 are your best bets as for speedos but for 12 or 14 cells, i would go for a 8 or 9XL. Maybe a 10XL if you value runtime like me. Since you don't race with it, I don't think you would need as much runtime as I do, so a 10XL wouldn't be the best option. I would probably go for a 9XL. If a little less runtime doesn't bother you though, a 8XL would be fast and more powerful.

Thanx for the advice, squeeforever.

What kind of run-times do these motors provide?

Will there really be a signigicant run-time difference between a 8XL, 9XL, and 10XL?

I'm a bit confused my the rating on some of these motors. Everyone says that these XL motors are significantly faster and more powerfull then the Novak HV-Maxx set-up, yet the Novak motor seems to be rated at almost twice the rpm/volt speed.

HV-Maxx: 4400 rpm/volt
Wanderer 8XL: 1875 rpm/volt
Wanderer 9XL: 1667 rpm/volt
Wanderer 10XL: 1502 rpm/volt

Since I'm not looking at running an insane 18+ cells or 4s-6s li-po set-up, will I actually see a drop in speed?

No way. First off, the HV-Maxx is a sensored system, so it has less torque. Alot less. Which will mean that the KV will drop drastically under load unlike the sensorless systems. Plus, with the XL motors, you can gear higher to compensate for the low KV. If I'm not mistaken, the XL motors are rated for 1800watts??? The HV is only rated for 375 I believe. The 10XL, on 14 cells would give about 30 min. depending on how you drive. It goes down by about 5 or so minutes per turn.

Alrighty..........that's comforting.

What kind of gearing ar you guys running in these things?

I was running a 12t pinion on a 72t spur originally, and ended up dropping it to a 9t pinion/70t spur to keep the HV-Maxx cool.

The Emaxx tranny I'm using has a 28.1/1 first gear ratio, vs the 7.33/1 ratio of the Savage tranny. Something tells me this could create an issue trying to get geared high enough.

To be honest, I'm not really sure. I think you won't have a problem gearing it. I'm not really sure of the gear ratios of the diffs on a Savage or of my E-Revo, but I run a E-Maxx tranny and stock diffs with 20/51 gearing and a 10XL on 14 cells. I'll try and do some research on the diff ratios and try to convert it for ya.

The diffs are a bit of a lower ratio in a savage, I believe.

Where did you get a 51t spur? I thought the Traxxas ones only went down to 66 teeth?

Actually, they go down to 54. I have several NIP that I got with some other stuff I bought but the 51T is a Ofna mod1 pitch for the Strobe slipper. I would highly recommend upgrading to it.

2.92 revo diff ratio
3.31 savage diff ratio
I got more speed and run time out of my 9xl than my hv maxx.

and the 2nd speed of the e-maxx tranny is 1.76 to 1

You really need a mod 1 spur/pinion with these motors sooner or later.

Second gear in an E-Maxx tranny is actually 17.9/1, I believe.

The more I look at this, the more I think I may just try and swap in a Savage tranny.

I like having the electronic reverse, but I think the HPI tranny might prove to be easier to work with and more reliable in the long run.

Is there any easy way to lock out the "one-way" feature of the nitro trannies so you could use the reverse function of an electric motor/esc?

I appreciate that something like a Savage tranny with disc brakes and a reverse module will work, but is does seem like a lot of extra complexity and weight for something that a decent ESC would do for you anyways.

Thoughts or experiances?

The 17.9 is the over all gear reduction of all the gears added up. diffs tranny spur and pinion. I run a 3 speed trans with the mech brake and had the reverse modul but it would not hold my motor. It is down at the moment for the dog bones are twisting around like pretzels. I need a few parts before it goes back to together. If you want the motor brake I would use the emaxx trans. It is a tough item with steel idlers in it. You can run a two speed as well for more versatile use.

Thanx, coolhandcountry. That makes alot more sence. I just checked the Traxxas website, and sure enough, the E-maxx and T-Maxx run almost identical gear ratios.

Okay, maybe gearing this thing won't be as hard as I thought.

Now I just need to decide on the motor and ESC.........

I'm currently leaning towards a Quark 125 esc (I've heard good things, and I like the 5amp BEC), and 7XL, 8XL, or 9XL motor. It will be running on 12-14 cells.

So looking for some honest motor advice:

What's the difference between the Feigao XL, Nemisis XL, and Wanderer XL motors? Is it just the color?

I know some say the Wanderer has better bearings, but some seem to say they're the same.

The only thing I can find, is that the rpm/volt ratting on the wanderer xl seems to be a bit lower then on the feigao (8 turn is listed on this site as 1875 rpm/volt vs 2084 rpm/vo0lt for the feigao).

I ask because I have an opportunity to pick up a Feigao 540XL (8 turn) with a standard size shaft (3.2mm or 1/8") for $45 new. It seems like a good deal, but I want to make sure I'm getting the best motor for my application.

Thoughts?

Well I'm not sure were your getting that motor from but all XL motors have a 5mm shaft. The main difference between the Feigao, Nemesis, Wanderer, Cordite, etc. are the colors, or labels. The Wanderers however, do come pre-wired with 5.5mm connectors. The difference between the KV however is the simple fact that the Wanderers are rated under a load so the KV is lessened