jeepfreak1972

I run the ball drives on my MB. Tore a boot the other day and upon inspection I found that the splined plugable outdrives that go into the diff are cracked in 3 places on each one right where the balls fit in the grooves. The cracks are all the way through. I run this thing on my track now that it is finished and I think the punishment is to much with the monster tires. I put the stock unused dog bone set up in it and after 1/2 tank I split one of the out drives in half an twisted the bone a bit. What I am wondering is do any of you have this problem with ball drives on the Marders or Leopards with the stock nobby tires? Are these bigger tires putting that much extra stress on these parts? My plan is to use the MB for playing and get the Leopard race for raceing on my track. But for now I can't stay off the thing with the MB. I hope the ball drives on the Leo will not suffer the same fate. I had no problems with the MB ball drives before the 48ft tripple jump on my track started calling my name. Thing is, I land power off. I learned long ago to let off the gas just before you land or the spider gears go bang in the diff. I think it just the big tires. What do you guys think? I forgot something. What is the pn. for the center shaft in the ball drive setup and the pn. for the balls? I have the paperwork that came with them and the catalog and they are not in there. Only the ends, round black disks and the axle boots are listed.

jeepfreak1972

I overlooked one pn. on the ball drive paper work. Pn. 7080/2. It is not clear if it is the center shaft or the balls. Does the shaft come with the balls? (that sounds bad)

icecreamslick

My Feedback: (9)

I ordered the ball drives as a hop-up when I ordered my MB six months ago, but I have not installed them yet because I figured I would wear out the stock dog bones first. I have not worn them out yet.

You running a tuned pipe? The extra torque is probably wearing them out quicker, but they should still hold up better than they are. [&:]

Have you replaced or checked your ball bearings, lately? If they are worn out, couldn't they put added stress on the shafts that are trying to turn the wheels?

No more 48ft triple jumps!

jeepfreak1972

Yes I'm running an fg tuned pipe. My bearings are all good too. I was able to find the part # on Molzer Mowerys site. I sure wish FG put all their parts in the catalog so they were easy to find. Thank God for the internet or we would be screwed. I just wonder if anyone driving buggies with the small tires and have the ball drives have breakage like this. I plan on keeping it off the track when I get my Leopard race. I just thought of one more thing, I took out the rubber rings in the spur gear and replaced them with hard teflon ones from Hobbytek in Germany. That might be part of the problem too along with the 48ft tripple.

jimbo1890

I was expecting that type of damage from people running the steel spur replacment but not the plastic spur. Did you make the teflon bushes yourself?

Monstrous

when my marder was originally an MB i twisted 3 dog bones and wrecked 3 spurs

now that its a marder, the dogbones are fine and there is no wear in the drive cups, and i havent stripped a spur since i put marder wheels on, come to think of it, i havent broken anything since i changed it to a marder

Monstrous

chevyman_de

The Teflon bushings are not recommended for offroad use. The plastic spur gear will go belly-up in a hurry, even on a buggy, not to mention a MT!

ammdrew

the ball drives are useded in all the onroad cars, we ocasionally see one break. very seldom though and usually in relation to a wreck.

In the off road we see them split when they do not have enough clearence side to side. the bottom arm is adjusted to far inward and when the suspension colapses the dog bone is jambed into the end as the arm rises. this force then has to go somewere. Check to see you have movenent in the bone at all suspension movement levels.

kengentry5000

My Feedback: (2)

On my stock (no tuned pipe) Duratrax Firehammer I have a little "tearing" of the outdrives on the diff but the dogbones look fine. I bash my Firehammer pretty hard. I run the standard spike tires.

Ken

jeepfreak1972

I got the teflon bushings from Hobbytek in Germany. www.rc-car-online.

jeepfreak1972

There was no binding and there was side slop in the center shafts in all ranges of motion of the suspension. They are cracked every place a ball rides inside the groove from the inside out.

radio_controlled_mad

have cv ball drive on my marder race with steel pinion and never damaged output cup - but the rubber boots split for fun,i normally fill them with grease and cable tie the ends,is ball drive a stock part on the mb or mt - thought they came with dog drive!!!

jeepfreak1972

I took the dog bone setup off as soon as I got the MB and installed the ball drives.