Just tried to adjust my Powervalves- FRUSTRATED

jay87lx

jay87lx

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I read the write up multiple times and it just doesnt seem to be working for me,
1. I removed the servo cover
2. started the engine and then using the screw on the top of the carb rack I turned it until the idle went down below 900 rpm. It seemed that at that time my servo was going back and forth so I lowered the rpm further until it stayed still.
3. I loosened the 2 screws on the front most PV housing and put a 2.5mm allen wrench in there to make the correct spacing. It just seemed like the servo would keep moving even though the engine was running smoothly but at a low idle. It just didnt seem like I could tighten the cable adjusters to get the housing to tighten- should I be screwing them "INTO" the servo housing to tighten the PV housing.

I guess my question is do I adjust the PV with the engine running or once I lower the rpm's and the servo goes to that point do i shut it down?

Help before I go to the stealership
 
You can just use your choke to make the engine idel down. That way your idel RPM's are not messed up. Like mad said let it idel down to about 900 then kill the engine. If its not tightening up did you check for pull throughs? Cant remember from your other post if you checked that yet. Also loosen the cables all the way then put in the spacer and tighten. CCC
 
super1c said:
You can just use your choke to make the engine idel down. That way your idel RPM's are not messed up. Like mad said let it idel down to about 900 then kill the engine. If its not tightening up did you check for pull throughs? Cant remember from your other post if you checked that yet. Also loosen the cables all the way then put in the spacer and tighten. CCC
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I dont have pull through- That was the first thing I checked because I knew if I needed to have them fixed I would need to send them out and wanted to beat the winter rush.

I will try again and shut the engine down this time.
so when I lower the idle to servo will move, will it turn making the cable feed into the line back to the PV housing (counterclockwise) or will it pull the cable (clockwise)? then when it moves, kill the engine and adjust from there
 
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It will pull the cables in[counter clockwise], opening the power valves[at low idle]. When you are checking the gap you are actually checking how much travel is left in the cable when the servo has opened the power valves...obviously too much gap and the power valves are not fully open...too little or no slack will over stress the cables/valves.
Bob
 
More info:
-once you lower the idle, so it is barely running, shut the engine off with kill switch
-mark the housing with a marker where the notches in the cable "wheel" line up, this way you always can reindex the wheel where the open position is. The servo does not have a stop and will rotate 360 degrees thats why you have to mark it
-as you adjust the cable tension always ensure the marks remain lined up, you have to be very accurate with this and recheck it constantly or nothing will be right.

Hope this helps
Bob
 
sideshowBob said:
More info:
-once you lower the idle, so it is barely running, shut the engine off with kill switch
-mark the housing with a marker where the notches in the cable "wheel" line up, this way you always can reindex the wheel where the open position is. The servo does not have a stop and will rotate 360 degrees thats why you have to mark it
-as you adjust the cable tension always ensure the marks remain lined up, you have to be very accurate with this and recheck it constantly or nothing will be right.

Hope this helps
Bob
Click to expand...

Exactly-- the servo always moves when you're messing with the cables so it needs to be marked. I've been doing mine the other way for the past few years, take off the header pipe and adjust valves till they're flush on the inside. Seems to be working great.
 
To stop the servo pully from moveing use a set of visegrips on the pully and position them so they rest on the air box or use a rope or wire and hold them in place.This will not damage the pully just dont clamp down realy hard.Now you can feal the housing pulling tight when you adjust if your a guy in a hurry like i always seem to be when i put a wrench in my paw!
 
bluewho said:
To stop the servo pully from moveing use a set of visegrips on the pully and position them so they rest on the air box or use a rope or wire and hold them in place.This will not damage the pully just dont clamp down realy hard.Now you can feal the housing pulling tight when you adjust if your a guy in a hurry like i always seem to be when i put a wrench in my paw!
Click to expand...


Good tip! CCC
 
I built a switch box which connects the servo motor to a 12 V battery. Eliminates the hassle of having to mess with the idle to get the servo to the right position. Did not like the idea of having to reposition the pulley by hand. When I need to rest the servo pulley to the open valve position, I push the button switch on my wiring harness and the pulley moves to the full open position.
 
So when you are adjusting the valves you want the servo in the open position which puts the valves in the open position? so as the servo moves counterclockwise (open) it pushes the cable away from the servo toward the cylinder and pushes the valve further into the jug?
 
no when the servo pulls on the cables it pulls the valves out of the jug(away from piston).. The valves are there mostly to help increase low end power and when you are up in rpm's it opens it up for more flow.

Closed position = Valves close to piston (dont worry about it hitting your piston, there are stoppers there to prevent that

Open position = Valves pulled away from piston allowing more air flow at higher RPM above 5500 if im correct

no when the servo pulls on the cables it pulls the valves out of the jug(away from piston).. The valves are there mostly to help increase low end power and when you are up in rpm's it opens it up for more flow.

Closed position = Valves close to piston (dont worry about it hitting your piston, there are stoppers there to prevent that

Open position = Valves pulled away from piston allowing more air flow at higher RPM above 5500 if im correct

So the default is at 900 rpm the servo opens.

If your not sure 100% on these I would take it all apart and just check it out and try to understand completey how they work. Take the exhausts off and use your hand to feel them inside the cylinder to see how they are in Open position and closed position.

You will just want to adjust them until they are flush to the cylinder wall.

A easy trick instead of lowering the idle and so on... is using a 12 v battery... a lawnmower would have one in it.

I just used two wires... one on the ground other on the live... shoved the wires in the servo plug and it will go to the open position...
 
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jay-s said:
So when you are adjusting the valves you want the servo in the open position which puts the valves in the open position? so as the servo moves counterclockwise (open) it pushes the cable away from the servo toward the cylinder and pushes the valve further into the jug?
Click to expand...
a question? are your cables running on to the top of the servo pulley or on the bottom? the reason i ask is that when the servo turns counter clockwise it pulls the cables which opens the valves,if the cables are being pushed when the servo turns counter clockwise the cables are wraped around the pulley the wrong way,they should lead on to the bottom of the pulley.
 
I have added to my previous post.

When looking at the servo from the cable pulley side, counter clockwise rotation of the pulley wheel should be pulling on the cables[opening the power valves]

If you are just looking at the servo from a "motor rotation"point of view...you are correct that if the servo motor runs clockwise it would be opening the valves, counter clockwise would be closing the valves

LOL!! Clear as mud now??!
Bob
 
Scratch post 12- I feel like a moron now- I looked at the pic of the servo and cable routing in the tech section- My cables do run UNDENEATH the servo wheel- Thanks 9801SRX for bringing that up- I am not in front of the sled so I was going on memory and thought they ran over the top of the wheel so when it rotated couterclockwise it would push them toward the piston- I messed up-
Ok, so they should be adjusted at the 2.5-3.0 mm between housings when the servo motor is "open" (turned counterclockwise pulling the cables and thus the PV away from the piston) if they are adjusted correctly using this method, before I put everything back together and started the engine would the PV be flush with the piston wall as Ride Race Live says?
 
When the power valve is in the commanded open position the beveled end of the power valve should be flush with the contour of the exhaust port of the cylinder. If you run your finger up the top side of the exhaust port you will be able to feel the valves position.[obviously the exhaust pipes must be removed for this] Try moving the servo back + forth a little and you can feel the exhaust valves moving up and down. The optimum postion would be as flush as possible to give unobstructed exhaust flow when the servo has moved to the open postion.
Bob
 
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