Losi xxx-4
12-11-2005, 02:45 PM
#797
I don't remember the part # but you will know it is the HDD belt because the aluminum idler arm is slightly longer, the belt is longer and the idler has two bearings to ride on instead of one weak one.When I changed over to the HDD belt I was impressed at the setting I could run it at, slight bit looser and a ton free'er feelin'. Almost night n day with that set up. If anyone has a good hard pack indoor set up I would sure like to see it. Lookin for one for smooth surface blue groove mild to medium jumps.
12-12-2005, 05:38 AM
#799
that part number is for the complete HD belt kit and not just the yellow belt
http://www.doughtyuk.net/images/parts/A3277.jpg
also, the yellow belt is exactly the same length as the std green belt, the new arm you get in the HD kit has the extra long hole, but that is for the xxx-s when using the large roller.
it does have a new double bearing pulley which helps to keep the belt running straighter on the pulley
the yellow xxx-s/g+ belt is shorter, the yellow xxx-s belt came in the xxx-s g+ kit and does not fit in a xxx-4
http://www.doughtyuk.net/images/parts/A3277.jpg
also, the yellow belt is exactly the same length as the std green belt, the new arm you get in the HD kit has the extra long hole, but that is for the xxx-s when using the large roller.
it does have a new double bearing pulley which helps to keep the belt running straighter on the pulley
the yellow xxx-s/g+ belt is shorter, the yellow xxx-s belt came in the xxx-s g+ kit and does not fit in a xxx-4
12-12-2005, 06:38 AM
#800
Speaking of belts, I just installed the HDD belt. It was running fine. But, I have a problem, when I run my buggy in a long straight line and brake quickly, I hear a scratching sound. This didnt happen when I used the green one. Is it with the belt too loose? Or is it with the pinion/spur? I tried tightening the belt with the tensioner but I still hear the sounds. 
12-12-2005, 06:43 AM
#801
Is there a space between the slipper assembly and the belt tensioner? I've heard the weird shaped nut that you adjust with the tool comes loose unless you loctite it. My car was making weird noises. One of my slipper bearings was going out, only when I took it apart did I notice the slipper nut was sliding against the tensioner.
Last edited by Rysuleod; 12-12-2005 at 06:54 AM.
12-12-2005, 06:49 AM
#802
I'm not sure. I'll check it later. Maybe that's the problem and I hope it's not with the belt. I don't want to ruin my newly replaced belt. 
12-12-2005, 07:16 AM
#803
that scratching sound wouldn't be the belt skipping would it. At a high speed then one the brakes the belt should skip 3 or 4 teeth. Thats how ya know the tension is right. If you've never had this before you probably had the belt to tight and thats probably why ya have a new belt. If this is not the case sorry....
12-17-2005, 12:00 AM
#804
Is this scratching, slipping or whatever sound normal? I tried tightening the slipper clutch and to no avail. I tried running it, it runs good but when I brake it still makes that sound. . I also noticed that if when the belt is loose, it makes more sounds, so I tightened the belt. It was lessened but was still there. What part in the gearing or belt is slipping? Any ideas, tips and suggestions??? 
Thanks.
. I also noticed that if when the belt is loose, it makes more sounds, so I tightened the belt. It was lessened but was still there. What part in the gearing or belt is slipping? Any ideas, tips and suggestions??? Thanks.
Last edited by csdspeed; 12-17-2005 at 12:17 AM.
12-17-2005, 07:48 AM
#805
I am kind of new two this car also but I believe that the slipper was a problem in the past that the factory fixed by changing the threads from left hand to right hand or something to that extent. If you have the G+ version you should have the corrected slipper nut. Ok now for my question. I decided to try an Orion Revolution V2 11T Double (Blue version) in my xxx-4 g+. I ordered the pinion (19T) that was listed for that turn of mod motor in the manual but I am worried about having overheating problems. I also read that you can decrease the timing on the revolution motors to 12 degrees to make them run cooler also in a 4wd buggy. I would not be against going to smaller pinion like a 18 tooth because my local track is pretty tight with only one medium size straight. Also, I am running an Quantum Competetion 2 Esc. Any insites in on this potential problem would be appreciated.
Sport10
Sport10
12-17-2005, 08:26 AM
#806
Tech Regular
iTrader: (2)
I've had good luck on gearing Orion V2 motors as per XXX-4 gearing instructions. Sometimes I go down a tooth or two but not often. The Quantum 2 is perfect. I use a Capacitor (worlds kit) on my Q2. The timing on the motors is usually set at the factory. I Believe they compromise between speed and long life.... For the most part. So I usually leave the timing alone.. however turning it down a few degrees would benefit more than harm your motor.
12-17-2005, 10:09 AM
#808
I have found the problem in my slipping xxx-4. When I tighten the tensioner arm and run the buggy, it loosened after a while. So that's why the belt still slips. I just thread-locked the screws for the tensioner and the problem's gone. 
12-17-2005, 01:18 PM
#809
ok I'll ask again, One the grapite plus the rear shocks are on the oppoisite of the regular xxx4, Meaning they are mounted on the rear a arms, one the regualr xxx4 they are on the front of the rear a arms. Do I need any mods to do this to my regualr xxx4 with out screwing up the suspension
12-17-2005, 01:36 PM
#810
Tech Regular
iTrader: (2)
You need NO modifications to swap the shocks to the rear of the arms and tower on the XXX-4. A couple of guys at our track put the shocks on the FRONT with The XXX-4G+. I have a XXX-4(not G+) and I have mine on the rear. On the Quantum 2, I use the default map that comes standard from the factory. It seems to work well with the Modified 4 wheelers.
