Thinking about doing a Berg but have questions

[tubed-n-lubed]

I am thinking about doing a Berg but have questions, actually think of doing 2 of them. A racer & a crawler.

I use an M11 now for all of my rigs & like the radio so I will probably run switches, I have been searching but don't see an all in one source for my questions. If there is one please let me know. Or sort of a newbie's thread on the world of moa.

Depending on the setup does a dual motor moa use batteries twice as fast as a shafty?

Does it make a difference on run time if you use 1 or 2 esc's?

Most of my concerns on battery life apply to the racer more than the crawler but with my approach to chassis design, CG & overall weight the battery requirements become a concern either way.

I guess those are my main concerns to start but I am sure I will have more questions.

Thanks for your help.

[tubed-n-lubed]

Also have axle choice questions, with all of the problems on the bully & raptor axles what are the strongest/best stock axle? Berg, HR ax10 replacement or something I have not seen/considered?

Or is the Bully axle fixed yet?

[LincolnBlack]

The strength of the berg axles is proven, I don't think you'll have much problem with strength. I haven't heard much about the other axles, so can't comment there.

As to your other questions.

How fast a MOA uses a battery compared to a shaftey varies depending on setup. If you were running the exact same electrics setup on both, I'd say more - but not double. Even though you have two motors drawings current, each motor is sharing the load so the current draw is less per motor than a shaftey with one motor drawing all the current.

Two ESCs would probably reduce run time a TINY bit as the battery has to run another ESC. But chances are you wouldn't notice. What servo you run would probably have more of a impact on battery life than an extra speedy.

Don't know a lot about the M11, but I wouldn't fork out the extra hard-earned for another speedy unless your radio can take full advantage of it.

[Tyler Kadlec]

Ive got raptor 2 axles on mine and running 2 escs with the dx6i, Had switches but they dont work that good but the dual esc works really good, My axles are shortened also, really beefy.

[Rocksolo]

Originally Posted by tubed-n-lubed

I am thinking about doing a Berg but have questions, actually think of doing 2 of them. A racer & a crawler.

I use an M11 now for all of my rigs & like the radio so I will probably run switches, I have been searching but don't see an all in one source for my questions. If there is one please let me know. Or sort of a newbie's thread on the world of moa.

Depending on the setup does a dual motor moa use batteries twice as fast as a shafty?

Does it make a difference on run time if you use 1 or 2 esc's?

Most of my concerns on battery life apply to the racer more than the crawler but with my approach to chassis design, CG & overall weight the battery requirements become a concern either way.

I guess those are my main concerns to start but I am sure I will have more questions.

Thanks for your help.

check this build, he has the M11 and 2 FXRs Daiki's berg バーグビルト

[ncgoose]

It is my understanding that the Bully axle issue has been corrected. Don't let anyone full you, Bergs DO have similar problems, but the solution is to replace the stock stub axles with the AX-10 stub axles. I have broken all 4 of my stock Berg ones over the course of 2 weekend outings.

As far as the electronics go, I think you got the answers to those.

At the end of the day, most of the MOA axles have their own issues, whether it be stub shafts, axles, etc. I would say go with what you feel comfortable and can afford.

I am getting ready to switch over to Bully's, but here is a list of what was done to my Bergs to get them ready:

Clocked Front
Clocked Rear
Fubar lockouts
Rear spindles machined to remove the arm (due to the lockouts)
Replaced all stub shafts with Axial versions

Compared to what I am expecting to do with the Bully's to get them ready:
Nothing since they are already clocked and locked. They might still clown wheel, but I have seen nothing but GREAT things from RC4WD on making the issue right with it's customers.

Enroute and I guess Newage now, does not actively support the U.S. market as far as I can tell.

I cannot accurately comment on the Hot Racing MOA's, but we do have several of the states top drivers using them. Each has commented on having to replace axle shafts.

In the end, do your research by seeing each up close and talk to the driver about problems they have had.

[tubed-n-lubed]

Thanks guys! Although I have some answers now they have lead to more questions as I suspected

I am looking at the HR ax10 axle & the Berg now. I currently 4 rigs with Axial axles & could probably build 2 more with the spare parts, I am looking at the HR for the width & the fact that it uses parts that I already have along with the wheels that I have will work as well. With Axial axles, DNA assassins & HB Rovers my comp rig sits at 10". With axial axles & Cyclone wheels my scale rig sits at 9.25". The raptors are too wide for me I think & the bergs would require a whole diff inventory of wheels to keep it narrow.

I am tired of transmissions, dig units & drive shafts, so I will be going MOA.

I just finished this racer 2.2 Rock Racer build

And in there is a video of how I have been driving it with no breakage as of yet. It was built for fun & the day after I ran it for the first time I found out that my club is throwing a King of the Hammers style rock race in 1 month so now I am getting serious about the racer & am thinking MOA.

Depending on how I like working with moa axles I may replace my comp rig as well. New Losi (mrc) bodied tuber But I will really have to like them.


I assume that 1 FXR will work to power 2 motors or is there a better ESC that I am not considering? I will stay with brushed motors on the moa I think as my comp rig with the goat loves to eat CVD's.

There used to be a thread/diagram that I had seen on wiring up the switches but now that I need it I can't seem to find it.

I thank you guys for your answers & patience with my MOA newbie questions.

I am off to research all of the axles some more.

[ncgoose]

Good luck with the search - and we will be here to answer more questions.

[Rocksolo]

[quote=tubed-n-lubed;1719360]Thanks guys! Although I have some answers now they have lead to more questions as I suspected
2.2 Rock Racer build
New Losi (mrc) bodied tuber
nice welding, great builds, love the mini losi tuberif only I knew how to weld. I am going to settle with the TCS eclipse I think

I assume that 1 FXR will work to power 2 motors or is there a better ESC that I am not considering? I will stay with brushed motors on the moa I think as my comp rig with the goat loves to eat CVD's.

1 FXR 2 motors
Rocksolo's berg - WILBERFORCE

There used to be a thread/diagram that I had seen on wiring up the switches but now that I need it I can't seem to find it.

here you go; wiring diagram for berg with dig switches
My Dig Switch Box!

[tubed-n-lubed]

Thanks Rocksolo that helps a lot!

So is the change to axial stubs the big fix for Bergs, are there other weak points that I need to consider?

[tubed-n-lubed]

I love this site! A few dozen hours of research & I think I have a setup to start with.

BERG axles (when I found that the HR axles fix was to run Berg shafts that decided it)
Tekin FXR (I would go FX-pro but I still want reverse)
Motors (I haven't decided yet but I have a bunch of singles to test for turn count & pinion size)
Switched dig setup (25 amp)
Axial stubs (I have 4-5 pairs already)
JPcustoms lockouts (unless you guys can suggest something better)
Wheels (we will see what I like & if the cyclones will fit as they are narrower than the Berg offset I think)
HB Rovers for tires on the crawler & HPI Grabbers for the racer
Hitec 7955 steering servos for both
I have never looked at little servos so what do you guys suggest for the dig? I wish that someone offered a dual relay solid state solution for the dig (ideas coming to mind as I type this!)

I will do a tuber for these that will take advantage of not needing the skid width for a trans.

What am I forgetting?

[tubed-n-lubed]

Ok I just got a scare of having a 45T limit on the FXR when running dual motors but then I realized that I am still thinking shafty & the ratios must be different on the Berg axle since there is no trans.

So I need suggestions on motors & pinion sizes to start with for a rock racer & a crawler.

Wow I am glad that I didn't finish my order yet, on hold until I get some ideas.

[APESHAT]

FXR-Pro w/ Fwd-Brake-Reverse. . .#TT1093
Unless Tekin says more, Main difference is "On resistance"- 0.000075 FXR/ 0.00003 FXR Pro
and its a bit over 5mm taller. . .+$30
smoother power delivery I'm told w/ less ^^, we'll see.

[tubed-n-lubed]

Originally Posted by APESHAT

FXR-Pro w/ Fwd-Brake-Reverse. . .#TT1093
Unless Tekin says more, Main difference is "On resistance"- 0.000075 FXR/ 0.00003 FXR Pro
and its a bit over 5mm taller. . .+$30
smoother power delivery I'm told w/ less ^^, we'll see.

Wow I need to step away from the puter for a while! I have been on the Tekin site a few times today & didn't scroll all the way down to see the FXR-Pro!

Thanks!!!! Now I will finish my order because with that esc I don't have to worry what motors I end up needing (within reason).

[ncgoose]

Axial axle stubs are the big fix for bergs.

JP lockouts are good, but not my preference due to the size. I run fubar lockouts, but John (MTHead) is a friend of mine and I like to support the local guys first.

Get the order done

[tubed-n-lubed]

Originally Posted by ncgoose

Axial axle stubs are the big fix for bergs.

JP lockouts are good, but not my preference due to the size. I run fubar lockouts, but John (MTHead) is a friend of mine and I like to support the local guys first.

Get the order done

I will look into the fubar units as well, thanks.

I am working on the order & had an idea about the dig & burning out switches so I dug out my car electronics box to find some relays. I am going to try the dig setup with relays instead of switches that way I am working with components that are designed for 30 or 40 amp load & if it fries one it will be easy to pull it & replace it. The pic is of spst but I will get spdt relays so it will work the same.

[Rocksolo]

I run the JPcustomrc lockouts......they are about 1mm (one) taller than the stock knuckles so clearance is not an issue, and i ended up with a spare set of knuckles so I was able to drill / tap / trim a set without being too nervous about screwing one up I think I have good steering now.

oh, planned on 35t motors with my FXR but the 50t venoms I had has plenty o torque and mad wheel speed with a 2 or 3 cell lipo

[tubed-n-lubed]

Yeah I think I like the JPcustom lockouts the best, there are others but I don't really want to grind the (C) area down to use straight tube lockouts.

I keep thinking about gearing & keep having to remind myself that I will only be dealing with a trans front & rear & not the reduction of a ring & pinion on top of that.

I think I will go with the FXR-pro just so I can have a little play/safety room, the specs are unlimited for motors. If I can find one.

[tubed-n-lubed]

Rocksolo, do you have this much speed:


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

Or do you think that 45T motors with 12 or 14T pinions would achieve it?

[LincolnBlack]

Possibly. Just by looking at the video, it doesn't look that dissimilar to 50t's w/12t pinions on 3s. But then the video might be misrepresenting the speed its doing....