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Thread: HPI RS4 Sport 3
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Old 09-18-2015, 06:01 PM
  #264  
Endaar
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Join Date: Jul 2015
Posts: 28
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Originally Posted by Billy Kelly
For the most part you are correct. This is the first vehicle of the 70+ I've owned that has a "must upgrade". The dog bone issue is unacceptable. Add the heavy body that effects how it drives. With oversized tires that limit replacement options.
The vehicle is flawed. The sealed drivetrain is nice. But doesn't excuse the out the box issues.
I've also got steering issues. Not just the tiny rocks getting under bell crank. Car almost has bump steer. When trying to drive straight it will pull to left or right sometimes. With mine if I push up on ft/rear arms, they flex. Push up on the front of an arm, it bends. Not like any other road car I have.
To me it seems that it was built with form, not function as priority.
I agree completely on all points.

With regards to the steering...I took the whole front end apart earlier today. Anywhere it was even possible something was binding I used the dremel to grind out some extra clearance. I cleaned the bearings, lubed everything, etc. The steering rack is definitely not binding. It seems to me the steering linkage is just poorly designed. I don't even think it is bump steer as the problem is clearly visible with the car stationary.

Check out this video. (You may need to download and then view; it wouldn't play in the browser for me.)

On the left is the Sport 3, with standard TC tires, an upgraded SF-50 servo, and CVDs. On the right is an RS4 Pro 3 Nitro SS, bone stock, with the same tires, and an SF-1 servo comparable to the standard one in the Sport 3.

Notice how the Sport 3 rarely finds center, while the Pro 3 always does.

https://onedrive.live.com/redir?resi...nt=video%2cmp4

I don't see any way to fix this. Are some of you not experiencing it, or are some of us just more sensitive to it?

Endaar
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