Yamitriple
Member
Just wondering about what I should do with the power valves on first start up with a full rebuild. I have brand new jugs and pistons and seals. I also messed with the servo a bit and dont know if it's in the correct position. Should I start the sled without the pv connected to clock the servo let it heat cycle then hook up the valves and adjust them before the second heat cycle?
RB2001SRX700
Lifetime Member
there is a servo tool made for them. it hooks to the wire harness and then to a 12 volt battery. it will clock the servo for you and then you can adjust them from there. If you don't have one I sold my SRX and would be willing to part with it
Yamitriple
Member
there is a servo tool made for them. it hooks to the wire harness and then to a 12 volt battery. it will clock the servo for you and then you can adjust them from there. If you don't have one I sold my SRX and would be willing to part with it
Okay yeah text me 9897218301.
Mac
Member
Yes agreed the 12 volt tool works well to adjust the valves. I always adjusted the valves with that tool when the heads were off so that i could see and feel the position in the exhaust port. With the pipes off you can feel the valve height relative to the top of the port. Remember not to adjust the valve to high in the port that the valve bottoms out. I think that must cause a lot of the valve pull through. I have more than 10K miles without pull through.
---mac---
---mac---
Yamitriple
Member
If I dont need the tool I'd rather not buy it, I get how to do it without it, I just am unsure about the motor being totally new and them being god knows where on start up. I have 3 new cables and I dont want to snap them on the first heat cycle lol. With out the tool should I just start it and go about the process immediately of lower rpm below 900 to clock it, turn it off adjust, then go about my first heat cycle? Also should I just have the cables disconnected from servo on the first start up just to be safe on where it clocks? Cuz I know it goes full open when in clocks
Mac
Member
It does not matter what position your valves are in when starting the motor. Open closed or anywhere in between makes no difference. You could pull the valves out altogether as long as you cover the access hole on the cylinder. Disconnecting the valves would be fine. The valves pull up to increase the port height when the engine is near max RPM. So running the engine on start up and adjusting RPM and a few cycles wont make any difference.
When you said snapping cables ..... i almost fell out of my chair. The discussions regarding power valves and adjusting them over the years have amazed me. Once the engine is assembled and exhaust installed i have no idea how you or others can adjust the valves. You cant see them. You cant feel them with your fingers. Please for the lov of Pete someone tell me how its done. Maybe i missed that chapter. And please no hocuspocus put a drill bit as a spacer voodoo.
You should buy the harness. Pull the pipes. And adjust the valves flush with the top of the exhaust port.
When you said snapping cables ..... i almost fell out of my chair. The discussions regarding power valves and adjusting them over the years have amazed me. Once the engine is assembled and exhaust installed i have no idea how you or others can adjust the valves. You cant see them. You cant feel them with your fingers. Please for the lov of Pete someone tell me how its done. Maybe i missed that chapter. And please no hocuspocus put a drill bit as a spacer voodoo.
You should buy the harness. Pull the pipes. And adjust the valves flush with the top of the exhaust port.
Yamitriple
Member
Lol okay I just was gonna go off from what the tech section says if I can get the tool sweet, if not I'll just have to make due, this is my first powervalved motor so I'm ignorant to it haha. Just wanted to make sure there wasnt any big whoopsie I could pull right off the bat. Thanks mac
Yamitriple
Member
Also just was most curious about clocking the servo I've read countless threads now and I know you experienced guys are tired of answering stupid questions, but not ever doing it yourself makes it difficult to get fully with just reading on the web
Yamitriple
Member
Also can u feel the exhaust port with the flanges still on the motor?
SRXChris
Member
I wouldn't worry about snapping cables, leave plenty slack and they will be fine. Servo will cycle to home position when you start it up, mine does. I adjust the way many others do and the way manual tells me to other then putting power to servo.
MURDER YAMAHA
VIP Life Member
You have to idle it down past 900 rpm, choke helps accomplish this.
Easiest to do with servo motor cover off so you can see when it returns to the home position, then kill motor.
Easiest to do with servo motor cover off so you can see when it returns to the home position, then kill motor.
Also place a mark with a permanent marker above servo when it's open in case it moves on you while adjusting so u can put it back to open before adjustment. I also use the servo tool and take the exhaust off for adjustment. I just did my sled with the 2.5 allen key way and then felt the port and i was alittle off. Taking exhaust flange off in my opinion is the best way.
Yamitriple
Member
Okay sweet, I just wanted to avoid taking flanges off since I torqued them before I installed the motor and they are a pain the get a torque wrench on but I'll do the the Allen key check and pull the flanges and see if I can feel where it's at in relation to the exhaust port. How long does it have to idle below 900?
Yamitriple
Member
Oh wait, if I understand this correctly you cant check the exhaust port by hand without the tool right? So unless the guy from earlier gets back to me about the tool I just have to do it the with the Allen wrenches and what it is is what it Is lol
MURDER YAMAHA
VIP Life Member
The tool is not needed. It does the same thing as idling the sled down and shutting it off.
Mac
Member
So I guess what didn't like most about the idle down process is that its a one time lower RPM and shut off the sled. Trust that nothing moves. Then remove the pipes make adjustments and hopefully you did it right. Then reinstall the pipes. You cant test anything because there is nothing you can see.
What i do like about the tool it allows you to activate the servo and watch the servo movement and see or feel the valves and make adjustments. Then rotate the servo by hand back to the start seeing the valves drop. Then active again.... and again.... ensuring it repeats. It always takes me several adjustments until I like it. Then reinstall the pipes. By seeing this process repeat several times gives me a sense of confidence.
---mac---
What i do like about the tool it allows you to activate the servo and watch the servo movement and see or feel the valves and make adjustments. Then rotate the servo by hand back to the start seeing the valves drop. Then active again.... and again.... ensuring it repeats. It always takes me several adjustments until I like it. Then reinstall the pipes. By seeing this process repeat several times gives me a sense of confidence.
---mac---
Mac
Member
Yamitriple - Pm your address. I will just send you the harness. Send back when your finished. What could go wrong.
Yamitriple
Member
Mac that is super cool of you man. To tell you the truth I dont need it perfect and as much as I appreciate the offer I'd rather not risk anything happening to your tool. If I can buy one myself I'll do it by the books
Mac
Member
My offer still stands should you change your mind. I went out to my garage and was gunna take a picture of it. Its just a simple plug in with a fused connection and a couple of wires to connect to a 12 volt battery charger to energize the servo. That didn't work out so well because " Jersey Joe" another member here called and said its hanging on the shelf in his garage. I ride with Joe every winter and will see him soon. He offered to put it in an envelope and send it off should you need it. Cheers.
---mac---
---mac---
mod-it
Member
I've always just took the servo cover off, started the sled, let it warm up a bit until it doesn't want any choke, and then flip the choke to the full position. When the motor starts choking down from being so rich I can watch the servo move to its under 900 rpm position. Kill the sled while watching servo to ensure it doesn't move, and then draw a line on the servo with a sharpie. Loosen power valves up until I can get a 2.5mm allen into the gap on each side, making sure allens are turned so flats are aligned, and then snug up the power valve housing until it holds the allens in place...easier if a buddy holds the allens. Adjust cables after making sure servo still lines up with sharpie mark. Then repeat two more times.
It has always hit the same peak rpm for me after I actually had to adjust them a bit. Good enough for me.
It has always hit the same peak rpm for me after I actually had to adjust them a bit. Good enough for me.
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