A Sticking Throttle Made Running Difficult, But After I Found The Solution It's Time For Another Vid...
Hmmm.... I love my Nitro Touring cars, I've got two HPI Nitro RS4 RTR 3 Evo's, a BMW and a Viper, but they can be a pain in the behind when something goes wrong. After fixing the bits after my last crash in the Viper, I was dismayed to find that the throttle on the Viper was sticking open a little, meaning the the idle speed at tick-over was way to high, leading to it running away and me having to apply the brake all the time.
With an electric car this would have just been a case of adjusting the speed controller, but with these little Nitro Radio Control cars it is a little more complicated.
I played around with the throttle linkage for ages, adjusting the throw, comparing it with my Nitro BMW, all to no avail. I re-lubricated all the moving parts but it was still opening up too much. What I did notice was that the throttle only seemed to be opening up too much after the brake had been applied, and this gave me a clue on how to solve the problem.
Where I had gone wrong was that during my after-run routine, where I check the tightness of all the nuts and bolts on the car, I had tightened the servo screw too much on the throttle servo. The throttle servo on the RS4 also operated the brake, and as the brake was being released, it was dragging the throttle open as the brake returned to its rest position.
Loosening the servo horn a couple of turns and the throttle and brake could work independently, and a smooth, low, idle speed was regained. Sorted! I was so chuffed with having my Nitro Viper touring car back in action that I took it down to the nearest car-park for a quick blat, and that's what you can see in the video above.
Comments / Questions:
Add A Comment / Question: