Rear motor stall fwd only

[losiking1]

As stated earlier you should check for binding or drag in the gearboxes. Also a quick check would be gear mesh.

[Charlie-III]

Originally Posted by jmindek

As a side note:

I don't think I understand the difference between parallel and serial. I actually meant to say that I have them wired in 'parallel'.

I will have to search the forums for that unless someone feels generous and would like to post the explanation and an example to illustrate that here.

A series connection for a single ESC/dual motor would be:
-ESC red output wire to 1 motor red/+
-From that same motor black/- to the 2nd motor red/+
-From the 2nd motor black/- back to the ESC black motor connection.

A parallel connection can look like a "T":
-ESC red motor wire goes & splits to each motor (1 red, 1 black)
-ESC black motor wire wire goes & splits to each motor (1 black, 1 red)
You have to mix the motor tab colors to allow one to spin in reverse on a MOA.

In a series connection, is a wire breaks or a motor dies, everything dies.
In a parallel connection, if a motor dies the other motor still works.

Some of your issue may be the different brand motors and I will also hazard a guess that one is "advanced timing" and the other is "retarded timing" since they are not crawler specific motors but timed for more "normal" applications.

[JohnRobHolmes]

It could be a brush hanging causing it to stick. Try lifiting the rig off the ground and running it at 30% throttle for five minutes and see if it cures is.

Is the venom motor timing adjustable?

[Zapped]

Pics always help! Also, check the timing on the motors, as Charlie-III said. The rear motor is reversed and needs to have reverse timing, or set both motors to zero timing.

[Charlie-III]

Originally Posted by JohnRobHolmes

It could be a brush hanging causing it to stick. Try lifting the rig off the ground and running it at 30% throttle for five minutes and see if it cures it.

While I hate disagreeing with you, due to the limited runtime on these motors I feel a hung brush is a low percentage issue........not over-ruled...but low percentage....even on "low budget" motors......

[AddictedtoRC1]

I hope you get it figured out my friend. I am curious as to what the problem is.

[jmindek]

Hi all. I had family over today. While I was showing off my humble XR10 it suddenly stopped. I had only about 3 minutes run time on a freshly charged 1300mah 2S lipo.
I fear the my ESC is defective or damaged or fried.
I hope to do some diagnosis tonight or tomorrow night. I will surely keep you posted.

[jmindek]

Once I looked at my XR more closely I see that the red wire has been pulled out of the on-off switch.

When I connect the wire where it belongs, it's back operational (and with the problem I started this thread on).

[jmindek]

I removed the on-off switch and soldered the red to black wires.
Then I got back to diagnosing the main issue.

I removed the rear axle, then the rear motor.

I put the rear motor in a motor stand, connected the motor leads, connected the battery to the ESC then tested.

I held the front left wheel and pulled a little throttle. The rear motor turned. It didn't matter how much I limited front wheel spin, the rear motor spins.

I had only enough time and energy to do that and post the results.

Does this suggest that the issue is with the rear axle gears?

[AddictedtoRC1]

Only one way to find out. Tear it all down and check the internals. Make sure there are no screws from the top link mount coming through the axle housing and that the axle shafts aren't rubbing on anything. Still confusing though as to why it would run one way but not the other.

[jmindek]

Ok problem is solved.

I tore down the rear gear box. I carefully reassembled it, and put the large gear box cover on. I checked the gear spin and felt a lot of resistance so I loosened the screws holding the large gear box cover.

Then I carefully meshed the pinion gear and locked the motor into the gear housing.

Before going further I connected the motor to it's leads and t
tested forward throttle with the front wheels in a bind.
The rear motor turned during slow and fast.

So I went ahead and finished the assembly, did the hardwood floor test and it passed!

Thanks for all your help!

[JeremyH]

Where should I send the bill?

Glad you got it figured out.

[losiking1]

Glad you got it sorted out. Now go out and have fun!!!