rubbersidedown
New member
I have an 02 viper. I was getting an intermittent power valve code. When I went to clean and reset them I noticed that a cable was out of its slot. So I put it back set the valves all good. Took a short ride about 30 miles and I got the code again so I pulled the servo cover and the cable was moved again. Now I watched as I turned the key on and the servo rotates clockwise about 3/4 of a turn before it rotates back counterclockwise. At this point the cable comes out of its grove and this time didn't fall into another grove but got hung up on the ridge. Does this mean my servo is bad? The cables are all pretty kinked up at the ends from this happening, so I have to replace them for sure. Will I do any damage if I ride without the cables connected?
Are your cables wrapped around the servo drum in the proper direction?
When looking at the servo drum from the left hand side of the sled, the cables wrap clockwise around the drum and the drum rotates counter clockwise when powered up to open valves.
rubbersidedown
New member
My cables wrap around the bottom counterclockwise as they seem to in all the tech pics for power valves. But you are saying that they wrap around the top of the drum
your correct rubbersidedown in your direction of the way the cables go on the drum, the servo opens via turning counterclockwise pulling on the cables.
Are you setting them to have a 2.5mm gap at the housing when open?? or are you using some other method, almost sounds like from your description they are too tight turning the servo backwards.
Are you setting them to have a 2.5mm gap at the housing when open?? or are you using some other method, almost sounds like from your description they are too tight turning the servo backwards.
rubbersidedown
New member
The servo turns clockwise first then counterclockwise. I even tried with the cables disconnected and it rotates clockwise then more revolutions clockwise then stops and in about 20 seconds rotates again unless I hold it to put some slight resistance on it. When I adjusted I had key on used 2.5mm allen wrenchs as spacers and adjusted until cable was slightly pulling the outer valve housing in. My spacing on the cable adjusters is pretty much exactly where I started and looks very close to all of the posts in tech pages and forums. If I ride without the power valves operating should I have them open or closed?
the servo is controlled by the cdi, so first you need to try another servo motor and see if it only moves in the 1 direction (u can just plug it in and turn on the key and see if it works right) and or another cdi to see if it corrects it, i have never had one do that (moves in 2 directions)but its electrical and anything is possible.
To ride the sled it will pretty much only run up to 7900-8000rpm and be quite flat feeling with the powervalves undone. If you lock the valves open it will run up to peak 8500-8600rpm rpm but be soggy down lower because the exhaust port is too high and loses torq, so its kinda a double bladed sword to run without the servo working correctly.
To ride the sled it will pretty much only run up to 7900-8000rpm and be quite flat feeling with the powervalves undone. If you lock the valves open it will run up to peak 8500-8600rpm rpm but be soggy down lower because the exhaust port is too high and loses torq, so its kinda a double bladed sword to run without the servo working correctly.