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Associated B44 front vibrations

Associated B44 front vibrations

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Old 05-08-2011, 02:34 PM
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Originally Posted by Jmuck69 View Post
I was thinking it could also be the pins in the actual CVA's are slightly working there way out and hitting the arm. Check the shiny pins in the axle are flush all the way around.
^^^agree with this also

IMO= in my opinion

epa= end point adjustment, also known as travel limit.
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Old 05-08-2011, 02:36 PM
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Originally Posted by Jmuck69 View Post
I was thinking it could also be the pins in the actual CVA's are slightly working there way out and hitting the arm. Check the shiny pins in the axle are flush all the way around.
They are. I checked the CVA's first, took the all apart and cleaned them, then made sure that they were all together.
You posted earlier about a droop... Is this what you are talking about?
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Old 05-08-2011, 02:38 PM
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Droop is how far the arm drops down. After looking at the video again, its fine when you have the wheels straight.
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Old 05-08-2011, 02:39 PM
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Originally Posted by Jmuck69 View Post
Droop is how far the arm drops down. After looking at the video again, its fine when you have the wheels straight.
I'll go ahead and post another video... It will be up in about 5-10 min.
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Old 05-08-2011, 02:42 PM
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hey muck, food for thought, when you turn to full lock on a b44 the inside tire (the one in the vid that bounces like a 2 year old) "cams over" and the steering link doesn't really hold it in position. With this couldn't an unbalanced wheel cause the severe vibration, which is only noticable when the wheel is turned.


sorry muck, can't remember if you have a 44 or not...
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Old 05-08-2011, 02:47 PM
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I currently don't have one...yet. I don't think its an unbalanced tire. I think its the CVA joint binding then releasing as it rotates. It's turned too far. Honestly without having the car in front of me, i'm just chasing my tail.
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Old 05-08-2011, 02:53 PM
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Ok, when you assembled the cv's did you use too much thread lock? I did that once years ago, and it caused the cv to bind. What happens is that the thread lock seeps in between the dog bone or axle and the large cylinder shape piece that the drive pins are locked into place with the set screw. But if you take the sv apart and there seems to be a hard film on the pieces, then just use a little sand paper to sand it down or something to scrape that film off.
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Old 05-08-2011, 02:56 PM
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Here is second video.
I'm beginning to think something is wrong with the servo stuff...
http://www.youtube.com/watch?nomobile=1&v=8ywknoQNKCU
Just posted it, may not be up for another 5 min.
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Old 05-08-2011, 02:59 PM
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Originally Posted by avtar4987 View Post
Ok, when you assembled the cv's did you use too much thread lock? I did that once years ago, and it caused the cv to bind. What happens is that the thread lock seeps in between the dog bone or axle and the large cylinder shape piece that the drive pins are locked into place with the set screw. But if you take the sv apart and there seems to be a hard film on the pieces, then just use a little sand paper to sand it down or something to scrape that film off.
No, I used no thread lock. The vibrations were happening even before I took apart the CVA's.
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Old 05-08-2011, 03:00 PM
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Originally Posted by Bugger234 View Post
They are. I checked the CVA's first, took the all apart and cleaned them, then made sure that they were all together.
You posted earlier about a droop... Is this what you are talking about?
Read your instruction manual, it will "simplify" terms like droop, camber, caster, antisquat, bumpsteer, etc. and your radio manual on epa,exp,etc.
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Old 05-08-2011, 03:00 PM
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Your all wrong, here is why.

The standard type of crossed Universal Joint, like you see at the end of a driveshaft near the rear differential on a full size pickup, is called a Cardan joint. If a single Cardan joint is used on a drive axle and the axle runs at an angle, then the axle actually accelerates and decelerates four time per revolution. On a pickup this vibration is taken up by a second single Cardan Joint near the output shaft of the transmission. If the output shaft angle of the transmission and differential input shaft angle are close to the same, which they are from the factory, then the two Cardan joints exactly cancel their vibrations. On an RC car, this small change in the rotational movement of the drive axles (vibration) is usually taken up by motion of the ball differential which transmits the motion to the axle on the other side and to the driveline. This does a good job of dissipating the excess vibration, especially if you have a belt drive. When you run a the car on a stand the vibration becomes a big problem. The diff no longer absorbs the vibration and the inner dogbone pin rocks back and forth in the drive cup slot. If your tires were out of ballance the car would vibrate just the same when the wheels are strait.
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Old 05-08-2011, 03:06 PM
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Originally Posted by ifuonlyknew View Post
Your all wrong, here is why.

The standard type of crossed Universal Joint, like you see at the end of a driveshaft near the rear differential on a full size pickup, is called a Cardan joint. If a single Cardan joint is used on a drive axle and the axle runs at an angle, then the axle actually accelerates and decelerates four time per revolution. On a pickup this vibration is taken up by a second single Cardan Joint near the output shaft of the transmission. If the output shaft angle of the transmission and differential input shaft angle are close to the same, which they are from the factory, then the two Cardan joints exactly cancel their vibrations. On an RC car, this small change in the rotational movement of the drive axles (vibration) is usually taken up by motion of the ball differential which transmits the motion to the axle on the other side and to the driveline. This does a good job of dissipating the excess vibration, especially if you have a belt drive. When you run a the car on a stand the vibration becomes a big problem. The diff no longer absorbs the vibration and the inner dogbone pin rocks back and forth in the drive cup slot. If your tires were out of ballance the car would vibrate just the same when the wheels are strait.
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Sorry, but I have no idea what you are talking about. Again, to all people. PLEASE read my signature. You mentioned somethings, but not how to fix it...
And hopefully your last comment was meant as a joke, or a pun.
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Old 05-08-2011, 03:09 PM
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Originally Posted by Bugger234 View Post
No, I used no thread lock. The vibrations were happening even before I took apart the CVA's.
Your steering knuckles are on the wrong side or your ballstuds are backwards, YOUR CAMBER LINKS SHOULD BE ON THE OTHER SIDE! they should be up front. this may be your problem
Associated B44 front vibrations-b4409.jpg
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Old 05-08-2011, 03:13 PM
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Originally Posted by ifuonlyknew View Post
Your all wrong, here is why.


I am smarter than all of you combined!
dude... did you even look at the video, he had parts of the car built wrong... but no.. ur "smart!" and we are all wrong..
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Old 05-08-2011, 03:19 PM
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Originally Posted by mini-t12 View Post
Your steering knuckles are on the wrong side or your ballstuds are backwards, YOUR CAMBER LINKS SHOULD BE ON THE OTHER SIDE! they should be up front. this may be your problem
Attachment 749348
The vibrations were happening before I switched those. Besides, they shouldn't make any difference because the vibrations are coming from the wheels jiggling side to side. I will switch this back, and post another video, but it looks like those arms interfere with the shocks.
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