R/C Tech Forums

Go Back   R/C Tech Forums > General Forums > Electric On-Road

Reply
 
Thread Tools Search this Thread
Old 09-12-2014, 04:47 AM   #1
Tech Fanatic
 
Salkin's Avatar
 
Join Date: Jan 2014
Posts: 882
Default LRP X20 shaft play?

I have an X20 4.5T motor. I have noticed that I can pull the shaft out approx. 1.5mm. I cannot push the shaft in.

It runs fine, though, no problem. Rotates fine, no strange sounds.

But is it OK to have this play in the shaft? Does it need to be shimmed?

Just can't understand how a slop/play can develop if it is shimmed properly from factory?
__________________
Yokomo BD7 2016 Black Series - MuchMore Fleta Pro / MuchMore ZX - Highest DLP650 - Sanwa M12
Salkin is offline   Reply With Quote
Old 09-12-2014, 07:11 AM   #2
Tech Regular
 
Conrad's Avatar
 
Join Date: Jun 2005
Location: Scotland
Posts: 470
Trader Rating: 3 (100%+)
Default

The magnets should keep in centered once in motion so you don't need to go nuts regarding shimming out all of the play, you still need some free play to allow it to spin freely during use.

I used to shim my brushed motors down to about 0.2-0.3mm of play back in the day. If you want to try it for yourself, put a pinion on the motor and spin the pinion a few times, the position the rotor ends up is where the magnetic field is strongest and holding the rotor in position. Add/remove shims to keep it in this sweet spot with some end play.

I know some people were deliberately shimming the motor to move the rotor closer to the sensor board to increase torque, personally I'd go for the sweet spot.
__________________
Swith Racing [www.swithracing.co.uk]
Conrad is offline   Reply With Quote
Old 09-12-2014, 01:35 PM   #3
Tech Addict
 
chasingthepack's Avatar
 
Join Date: Apr 2013
Location: hanworth uk
Posts: 728
Default

Quote:
Originally Posted by Salkin View Post
I have an X20 4.5T motor. I have noticed that I can pull the shaft out approx. 1.5mm. I cannot push the shaft in.

It runs fine, though, no problem. Rotates fine, no strange sounds.

But is it OK to have this play in the shaft? Does it need to be shimmed?

Just can't understand how a slop/play can develop if it is shimmed properly from factory?
no it shouldnt have play,take it apart,i bet the rubber o-ring is missing,i had the same problem,my motor kept cutting out on sharp left turns,the rotor moved away from the hall sensors and the esc would go to blinky mode,it should have 2 plastic shims but different thickness and a rubber o-ring,the thicker shim goes onto the pinion shaft first then the rubber o-ring,the thin plastic shim goes on the hall sensor side,ive just had the same thing with my orca tx so used metal shims to fix that
__________________
yokomo bd7 16_lrp works team-trinity d4 17.5_futaba 4pks_futaba bls
wet/damp car xray t4-14-r10 pro-team wave 17.5 savox 1251
chasingthepack is offline   Reply With Quote
Old 09-12-2014, 01:51 PM   #4
Tech Fanatic
 
Salkin's Avatar
 
Join Date: Jan 2014
Posts: 882
Default

Quote:
Originally Posted by chasingthepack View Post
no it shouldnt have play,take it apart,i bet the rubber o-ring is missing,i had the same problem,my motor kept cutting out on sharp left turns,the rotor moved away from the hall sensors and the esc would go to blinky mode,it should have 2 plastic shims but different thickness and a rubber o-ring,the thicker shim goes onto the pinion shaft first then the rubber o-ring,the thin plastic shim goes on the hall sensor side,ive just had the same thing with my orca tx so used metal shims to fix that
Thanks, I will take it apart for inspection.

UPDATE: took the motor apart, and sure enough, the rubber O ring was missing. I had a LRP repair kit with the O ring and after fitting it to the shaft with the shim, no more play or slop. Super
__________________
Yokomo BD7 2016 Black Series - MuchMore Fleta Pro / MuchMore ZX - Highest DLP650 - Sanwa M12

Last edited by Salkin; 09-12-2014 at 02:55 PM.
Salkin is offline   Reply With Quote
Reply



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off



All times are GMT -7. It is currently 01:27 AM.


Powered By: vBulletin v3.9.2.1
Privacy Policy | Terms of Use | Advertise Content © 2001-2011 RCTech.net