R/C Tech Forums

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

Reply
 
Thread Tools Search this Thread
Old 05-17-2007, 12:26 AM   #1
Tech Apprentice
 
Join Date: Sep 2006
Posts: 61
Default xxx 4 Drag in Drivetrain

Hello all,

I just bought a xxx-4 recently, and am new to the 4wd buggy scene.

A few weeks ago, the car was running great, until I broke the chassis. After replacing the chassis, there seems to be drag somewhere in the drivetrain. The car is slower overall, and when I go over a jump, the back end comes up, like I'm applying brake. In general, the car drives like it has drag brakes.

I checked the Novak 5.5 system, re-programmed it, checked all radio settings, and the problem doesn't seem to lie there. The diffs need to be rebuilt, but I wouldn't think those would be a problem.

With the motor removed, there seems to be friction when you turn the wheels. I currently have the HD belt and pulley system installed.

Has anyone come across this problem? It could be a bearing, but at what point do you replace belts? Do they stretch?

Also, I have the carbon fiber mod on the front diff case. Aside from tearing the car down completely, I wanted to know if there are any problem areas in the drivetrain so I can focus my efforts there first.

Any help would be greatly appreciated. Thanks!
Eggman is offline   Reply With Quote
Old 05-17-2007, 12:55 AM   #2
Tech Elite
 
Join Date: Sep 2005
Location: Mass.
Posts: 3,470
Trader Rating: 96 (100%+)
Default

Is the slipper assembly in the right way? There's a few shims and bushings that if not put in the correct order will affect the belt, or they may be missing altogether.
K.Copeland is offline   Reply With Quote
Old 05-17-2007, 08:17 AM   #3
Tech Master
 
Join Date: Oct 2005
Posts: 1,352
Trader Rating: 58 (100%+)
Default

In addition to the above, Don't get the belt overly tight. It tends to drag it a bit.
__________________
Where ever I may roam
Bigcheese is offline   Reply With Quote
Old 05-17-2007, 09:59 AM   #4
Tech Apprentice
 
Join Date: Sep 2006
Posts: 61
Default

Slipper Assembly is installed correctly.

Belt tension seems to be ok.
Eggman is offline   Reply With Quote
Old 05-17-2007, 10:11 AM   #5
Tech Elite
 
portyansky's Avatar
 
Join Date: Mar 2007
Posts: 2,983
Trader Rating: 54 (100%+)
Default

I dont have a xxx-4 but if you say your diffs need rebuilding, then I would do it. Check your belts and slipper assembly as well.
Good luck....
__________________
Team Tekno Canadian Team Manager
Team Hitec
portyansky is offline   Reply With Quote
Old 05-17-2007, 10:40 AM   #6
Tech Master
 
Join Date: Jul 2006
Location: Sugar Land, TX
Posts: 1,169
Trader Rating: 9 (100%+)
Default

Since it happened after you replaced your chassis, I'd check to make sure the belt isn't hitting anything first. It only takes a little to make it drag. If teh belt's clear, check your bearings. I'd check the ones in the slipper assembly and in the tensioner pulley first.
cjtamu is offline   Reply With Quote
Old 05-17-2007, 03:03 PM   #7
Tech Regular
 
Alltapdout's Avatar
 
Join Date: Feb 2007
Location: Great White Buffalo
Posts: 412
Trader Rating: 2 (100%+)
Default

If the tensioner hex is not tight enough/ or the washer with the elbow cut in it, is inserted wrong, the adjuster hex with contact the idler arm and cause drag.
There are two bearing in the slipper assy.
If you have the new machined idler gear then there are two bearing in it... If you are running the origional white pulley be sure to check that...I've replaced a few of those bearings...hense the upgrade.
Finally be sure to rebuild diff's and clean the side diff bearings..

Other than that...? Maybe the steering box insert is loose and causing drag.

Is you belt starting to fray??....If so I suggest a new one. A new belt is like a entire new car!!

Last edited by Alltapdout; 05-17-2007 at 05:17 PM.
Alltapdout is offline   Reply With Quote
Old 05-17-2007, 04:56 PM   #8
Tech Regular
 
Join Date: Feb 2004
Location: NW Arkansas
Posts: 403
Trader Rating: 3 (100%+)
Default

Make sure the giant slipper tension nut isn't dragging on the belt tensioner. I bought mine used, and it was rubbing badly. A shim or two fixed it easily.
__________________
AE FT B44.2, SC10, T4, B4.2, B4, 18T, 18R, TC4, L3.5O ** Losi MRC Pro ** CRC Carpet Knife ** Axial XR10, AX10, SCX10 ** Traxxas EMaxx ** JR Z1
Manning is offline   Reply With Quote
Old 05-19-2007, 12:48 AM   #9
Tech Apprentice
 
Join Date: Sep 2006
Posts: 61
Default

Well, after I pulled it all apart and inspected everything, I took a look at the belt and it was frayed a little on one side. I put a new belt in, and voila, she's back to new.

I had no idea a slight fray would make such a big difference.

Thanks to all those that helped and posted replys.
Eggman is offline   Reply With Quote
Old 05-19-2007, 08:54 AM   #10
Tech Regular
 
Alltapdout's Avatar
 
Join Date: Feb 2007
Location: Great White Buffalo
Posts: 412
Trader Rating: 2 (100%+)
Default

Ah ha. Glad to help sir! Good to hear everything is running smooth!
Alltapdout is offline   Reply With Quote
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
How free is your drivetrain? seaball Electric On-Road 121 04-21-2013 12:15 PM
Beef Up Drivetrain BuggyKing Micro and Mini Scales 11 10-23-2007 09:41 AM
tc3 drivetrain kh15 Electric On-Road 10 09-05-2004 09:38 PM
Drivetrain problem Committed88 Electric On-Road 9 05-10-2004 03:19 PM
Drivetrain Belt Potato Electric On-Road 1 08-05-2002 08:53 AM



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 02:24 PM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
Powered By: vBulletin v3.9.2.1
Privacy Policy | Terms of Use | Advertise Content © 2001-2011 RCTech.net