Why do things always go wrong while bashing...

[jnev]

Well since my Revo was finally built (finished about 2 weeks ago), I wanted to see how durable it will be. Last week I brought it with me snowboarding int eh mountains. It did surprisingly very well and ran flawlessly while jumping, drifting, etc. But today, I went to a local spot in the canyon where many bikers have built jumps. It is a pretty small and tight area so there isn't much room for speed runs. Everything was going well until about half way through the battery pack (30 minutes). When I am on the throttle going slowly, it is fine, but I just barely accelerate, it seems as if something slipping and there is a pretty bad grinding noise. The car also does not roll freely... if it rolling, once it gets to a certain spot, everything just locks up.

I went home to try to figure out the problem. I disconnected the front diff from the tranny and everything rolled smoothly. I then disconnected the rear diff from the tranny, and everything again rolled smoothly, so I know the problem does not lye there. I then disconnected the motor from the tranny. The transmission seemed to roll very smoothly (although I did not open it). I tested the motor disconnected from everything and it went smoothly also. So I thought maybe the problem is fixed without even doing anything. Well, I put everything back together (motor in, tranny, diffs, etc.). I held it in the air and everythign was smooth (unlike at the bash when I did this). So I put it down and accelerate smoothly, and it works perfectly. But then I hit the throttle just barely harder to gain speed, and the same grinding/slipping sound comes back.

My only guess is that the problem is in the motor, like it demagnetized or something.... I also forgot the mention that I did not smell any smoke from the motor, ESC or anything.

Any idea's what could have gone wrong? Do you all also think the problem is in the motor?

[lincpimp]

The magnet has come loose from the shaft. You may be able to glue the magnet back on. Do not run it anymore till you fix it, you may damage something else.

[jnev]

For some reason I am not that surprised this is the problem. Because it will be the second time it has happened to this same motor. Last time this problem occurred while running it in my 1/8 buggy. But I also sent it to Mike and he fixed it for me....

Do you have any idea what causes this problem with the cheap Feigao motors? I have never heard of this happening with Lehners, Neu, Pletti's, etc.

[squeeforever]

It happens to them all the time. Its not just the Feigaos. I did it to a Lehner, Larry (crazyjr) did it to a HV-Maxx, etc. Feigaos are just more common I guess. You can just use JB Weld on it and fix it.

[jnev]

I've never taken one apart, so we'll see what happens. Hopefully I am able to do it though... if I end up ruining it even more, it'll will be time for a Neu.

Do you have a flat spot ground on the shaft for the pinion set screw? I thought this same thing happened to me, but it turned out the pinion set screw had cut into the shaft all the way around, allowing it to slip.

[jnev]

I do have a flat spot and quite a big one if I may add. But I also took the pinion off when checking for problems and the shaft is good as new... well, except for the flat part. I think I will try the JB Weld or similar glue to put it back together, but I don't have high hopes...

BTW - how do you take the motor apart? Do you just push on the shaft toward the back of the motor or what?

lol again?

That stinks!

To take them apart, you just take the motor, and tap the shaft on a table or what ever, and the end bell should pop off....

I just recently had the plating around the rotor magnet come off. The magnet is still on the rotor but it makes a really bad ticking noise and heats up realy fast. Is there anyway to fix that? So they sell just the rotor anywhere. It was a Feigao 9L.

I've had the magnet seperate (2 Novaks, 1 Feigao) but never had the plating get ripped.

[jnev]

Thanks BOR. Sounds pretty simple to me.

bluonyx - As far as I know the rotor is not sold separately, which is why I had to contact Mike to fix the motor. I have no idea on the plating.... sorry. Hopefully it is just the rotor on mine.

[Getter Robo]

Loctite 603 or 623 is fine for re-glueing the magnet to the rotor, too.