Cogging problems 9920/7XL
 

Hello guys,

first of all, merry christmas!

I have been driven my savage today in the woods. And I had really bad cogging issues (wich I never had before). When the car was about 20 meters away, the car kept on cogging and drive really slowly. And the car was a few seconds out of control. The car didn't react on the commando's of the transmitter. When the car was in the range of 5-10 meters by me, the car responded well.

I had been made two changes to the truck. The motormount from a L form aluminium plate (50x80x1,5) to a 6mm motormount.

http://img286.imageshack.us/img286/2575/bl0723va.jpg

http://img286.imageshack.us/img286/2...ount0080ll.jpg

http://img286.imageshack.us/img286/9...ount0112cy.jpg

And I changed the steering servo from a standard HPI servo to an Kopropo 2015 FET servo. I connected the FET wire to the + of the receiver pack.

Could these two changes the reason for the cogging issues? Or does anyone have other possibilities? Let me know!

Let's knock on wood! Do you have another radio to try??

Was the steering acting weird?

Haha, I didn't have any problems with my Futaba T3PDF but since now I do.

I have an different radio to try, but that is also an Futaba. The steering wasn't acting weird. Tomorrow I will change the servo to the stock HPI steering servo.

Try and run it on that skate park. Might be some interference in that forrest? Like radio/ tv antenna's or the like.

If your using a UBEC, try a reciever battery pack instead.

My UBEC caused me loads of problems, inteference/stuttering etc'.

Also if you look at the last pic there is a receiver pack clearly visable;)

Is your new motor mount rubbing something.

I run a 9920 & 7XL with 14 cells, & a reciver pack (no ubec) in my mbx4 with no cogging what so ever.

Yeh.

I used a UBEC for 2 runs and hated it, a power pack does it loads better in my honost opinion. Not fussed about a little more weight and something extra to charge. :)

I had problems soldering the copper wires of the UBEC onto my ESC/connecters too...

The problem is solved. Thank you for all your inputs.

I changed the servo to stock HPI servo and the cogging and bad radio signals were gone.

I also tightened the slipper. The truck is now pulling wheelies! And the top speed is also higher! If I put the throttle to hard, the truck is flipping over. This is cool!

I am glad you found the problem out. sounds like you enjoying your truck. It is not a problem trying to help out a rc brother. :D